157292-3.pmd

Concord CXSD/H -

Installation & Servicing

GENERAL

Boiler

CXSD 40/H

CXSD 50/H

CXSD 60/H

CXSD 70/H

CXSD 80/H

CXSD 90/H CXSD 100/H

CXSD 110/H

CXSD 120/H

Number of sections

Flow tappings

Rc (in. BSP)

2 x 2 at rear

Return tappings

Rc (in. BSP)

2 x 2 at rear

Maximum static head

metres (feet)

61.0 (200)

45.7 (150)

Maximum pressure

bar (p.s.i.)

6.0 (87)

Gas inlet connection

Rc (in. BSP)

3/4 (3/4)

1 (1 )

Min. dynamic gas

mbar gauge

15.5

16.5

15.0

16.0

17.5

16.0

17.5

pressure required at boiler inlet in.w.g.

6.2

6.6

6.0

6.4

7.0

6.4

7.0

Electricity supply

230 Volts- single phase, 50 Hz, fuse 5 A

Nominal flue size (to BS. 835)

m m

150

175

200

250

in.

Diverter outlet socket

m m

184

213

238

288

internal diameter

in.

7.3

8.4

9.4

11.2

Length of burner bars (overall)

m m

377

497

617

737

837

14.8

19.5

24.3

29.0

33.7

Main burner injectors (3 off)

size, mm

3.4

3.82

4.12

4.57

4.86

5.2

5.3

5.5

5.6

Approximate dry weight

210

265

330

395

490

lb.

463

584

727

871

1078

Water content

litre

gal.

4.8

6.6

8.2

9.9

11.5

Table 3 - Boiler Control specification Maximum Flow temperature 85

Table 2 - General Data

Electricity supply

230V, 50Hz, fuse 5A

Ignition

5 attempts followed by non-volatile lockout.

Gas valve

High/Low and Off

Gas safety time

Maximum of 10 secs with 5 attempts with one min. between attempts.

Safety check

The control de-energises every 4 hours to check internal control functions.

Pump

Pump overrun operates if the flow temperature is greater than 75

Boiler thermostat

The boiler thermostat hysteresis is a maximum of 3

Table 1- Performance Data

Boiler

CXSD 40/H

CXSD 50/H

CXSD 60/H

CXSD 70/H

CXSD 80/H

CXSD 90/H

CXSD 100/H

CXSD 110/H

CXSD 120/H

Boiler Input

Gross

33.8

42.2

50.7

59.1

67.6

76.0

84.5

92.9

101.3

Low Rate

Btu/hr x 1000 115.3

144.1

172.9

201.7

230.5

259.3

288.2

317.0

345.8

Nett

30.4

38.0

45.7

53.3

60.9

68.5

76.1

83.7

91.3

Btu/hr x 1000 103.8

129.8

155.8

181.7

207.7

233.6

259.6

285.6

311.5

Boiler Input

Gross

48.3

60.3

72.4

84.5

96.5

108.6

120.7

132.7

144.8

High Rate

Btu/hr x 1000 164.7

205.8

247.0

288.2

329.3

370.5

411.7

452.8

494.0

Nett

43.5

54.3

65.2

76.1

87.0

97.8

108.7

119.6

130.4

Btu/hr x 1000 148.3

185.4

222.5

259.6

296.7

333.8

370.9

408.0

445.0

Boiler output

100

110

120

High Rate

Btu/hr x 1000 136.5

170.6

204.7

238.8

273.0

307.1

341.2

375.3

409.4

Gas rate

High

4.60

5.75

6.90

8.05

9.20

10.35

11.50

12.64

13.79

/h 162.4

203.0

243.6

284.2

324.8

365.4

406.0

446.6

487.1

Approx. flue

4.5% CO

&100°C.m

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.11

0.12

gas volume

4.5% CO

& 212°F. ft.

106

127

148

170

191

212

233

254

Manifold setting pressure

mbar

9.7

9.8

10.2

10.0

9.3

9.6

10.7

11.1

12.1

High

in.w.g.

3.9

4.1

4.0

3.7

3.8

4.3

4.4

4.8

Manifold setting pressure

mbar

4.8

5.0

4.9

4.6

4.7

5.2

5.4

5.9

Low

in.w.g.

1.9

2.0

1.8

1.9

2.1

2.2

2.4

Part load efficiency (Gross)

81.9

81.6

82.7

82.0

82.5

83.2

83.4

82.4

Seasonal efficiency (SEDBUK)*

[80.4]% [80.3]% [80.4]% [80.4]% [80.4]% [80.4]% [80.4]% [80.4]% [80.4]%

* This value is in the UK government's Standard Assessment Procedure (SAP) for energy rating of dwellings.
The test data from which it has been calculated has been certified by Advantica 0087.

Note. To obtain gas consumption in l/s, divide gross heat input (kW) by a calorific value of 37.8 (MJ/m

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Concord CXSD/H -

Installation & Servicing

GENERAL

CAUTION.

To avoid the possibility of injury during the installation, servicing or cleaning of

this appliance, care should be taken when handling edges of sheet steel components.

CONTENTS

Air Supply. ......................................................................... 8

Boiler Assembly - exploded view. .................................... 9

Boiler Clearances. ............................................................ 5

Burner Assemblies - exploded views. ..............................

CXSD 40/H-90/H. ........................................................ 26
CXSD 100/H-120/H ..................................................... 27

Casing Assembly. ........................................................... 12

Chimney System. .............................................................. 8

Commissioning. .............................................................. 17

Controls. ............................................................................ 4

Electrical Connections. .................................................. 14

Electrical Supply. .............................................................. 8

Fault Finding. ................................................................... 32

Gas Safety Regulations .................................................... 3

Gas Supply. ........................................................................ 8

Hydraulic Resistance. ...................................................... 5

Initial Lighting. ................................................................. 17

Installation. ........................................................................ 9

Mandatory Requirements. ............................................... 7

Option Kits. ........................................................................ 4

Pump. ................................................................................ 6

Servicing. ........................................................................ 24

Short List of Parts. ......................................................... 35

Site Assembled Boilers. ................................................. 30

Static Head Requirements. .............................................. 6

System Connections. ..................................................... 11

Ventilation. ........................................................................ 8

Water Circulation. ............................................................ 4

Water Connections. ......................................................... 4

Water Treatment. ............................................................. 6

Wiring Diagrams. ............................................................ 15

Concord CXSD 40/H - 120/H (Natural gas) B.G. Certified - P.I. No. 87/AQ/103

Destination Countries: GB & IE

INTRODUCTION
CONSTRUCTION

Boiler body
The sectional boiler body is of cast iron and is supplied assembled
on a sheet steel combustion chamber with an integral draught
diverter. The boiler can be supplied in sectioned form to special
order for site assembly - refer to the section headed `Instructions
for Site Assembled Boilers'.

Casing
The casing is manufactured in stove enamelled sheet steel and
is easily assembled on site.

Burners
The 3 burners are of stainless steel construction.

Current Gas Safety (Installation and Use)
Regulations or rules in force.

It is the law that all gas appliances are installed and serviced by
a CORGI registered installer in accordance with the above
regulations. Failure to install appliances correctly could lead to
prosecution. It is in your own interest, and that of safety, to ensure
that the law is complied with.

The Concord CXSD 40/H-120/H range of boilers has been tested
and certified by British Gas to prEN656 for use with Natural gas
only.

Multiple boiler installations

The Concord CXSD/H range is certificated for use in multiple
boiler installations, providing that the following conditions are
satisfied.

1. A downdraught thermostat kit MUST be fitted to ALL boilers

in the installation.

2. A maximum of 6 boilers may be used with a single flue

header.

3. For clearances see Frame 2.

A comprehensive guide to multiple installations of Concord
CXSD/H boilers is available.

WARNING. Failure to use a downdraught kit on every boiler in
a multiple boiler installation will negate the certification of the
installation and therefore contravene the essential requirements
of the Gas Appliance Directive.

Note. The CXSD 40/H, CXSD 50/H and CXSD 60/H boilers are
intended for use as commercial boilers and are NOT certified for
use in domestic applications. A domestic installation is defined
as an installation where the boiler takes its combustion air from
a living space or from a room directly or indirectly connected with
the living space. It is important, therefore, that no external control
devices - e.g. flue dampers, economisers etc., are directly
connected to this appliance unless covered by these Installation
and Servicing Instructions or otherwise recommended by
Caradon Ideal Limited in writing. If in doubt please enquire.
Any direct connection of a control device not approved by Caradon
Ideal Limited could invalidate the British Gas Certification, the
normal appliance warranty and could also infringe the Gas Safety
Regulations. Table 1, Table 2 and the descriptive notes which
follow contain all the essential data likely to be required by the
installer.

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Concord CXSD/H -

Installation & Servicing

GENERAL

Flow and return connections are 2" BSP.

A 1" BSP tapping is provided in the redundant return flange for
the cold feed or expansion vessel connection.

Safety Valve
A safety valve must be sized and fitted in accordance with BS.
6644 for every type of system. The valve should be set at 0.7
bar (10 lb/in.

) above the operating pressure in the boiler. The

maximum safety valve setting is 0.7 bar (10 lb/in.

) above the

maximum design operating pressure of 6 bar (87 lb/in.

Cold Feed/Open Vent
The independent cold feed and the open vent must comply
with BS. 6644 and be of the following minimum size.

Boiler Size

Cold Feed

Open Vent

CXSD 40/H - 50/H

3/4

CXSD 60/H-120/H

1/4

Sealed system filling point - refer to Frame 8

WATER CONNECTIONS

GAS CONTROLS

The gas controls consist of a high / low arrangement with
direct burner ignition.

ELECTRICAL CONTROLS

WARNING. THE ON/STANDBY [1/0] button does NOT electrically
isolate the boiler.

The CXSD/H incorporates an advanced microprocessor based
control system which operates all electrical functions of the boiler
including ignition, flame detection, thermostatic control, and high/
low operation. In addition, the microprocessor has onboard
servicing and commissioning instructions and a fault diagnosis
programme.
The illuminated LED display gives a continual read-out of the boiler
status and functions, but in the unlikely event of a fault condition
will display the fault areas.

OPTION KITS

Pressure Gauge Kit
A pressure gauge is available for the range of boilers. Details
for fitting are included with the pressure gauge.

Downdraught thermostat
This kit is optional when used on a single CXSD/H installation,
but mandatory when used on a multiple boiler installation.

Remote Indication Board (volt free)
This provides the ability for remote indication of lockout and
overheat conditions.

Outside Sensor
This kit provides a sensor for temperature compensation when
the outside temperature changes

DUTY

The range of boilers is suitable for: Combined indirect pumped
domestic hot water and central heating systems; Independent
indirect pumped domestic hot water or central heating systems.

Fully pumped systems may be open vented or sealed.

The range of boilers is NOT suitable for:

1. Gravity DHW systems.
2. Gravity heating systems.
3. Direct domestic hot water supply.

WATER CIRCULATION SYSTEM

Due to the compact nature of the boiler the heat stored within the
castings at the point of shutdown of the burner must be dissipated
into the water circuit in order to avoid the overheat thermostat
tripping. In order to allow pump operation after burner shutdown
the boiler control box incorporates a pump overrun facility which
operates when the boiler switches off and until the flow temperature
is below 75

C and, in order to make use of this, the pump must be

wired to the appropriate terminal L

(pump) in the boiler control

box.
1. The minimum flow rate as given in Table 5 must be maintained

whenever the boiler is firing and during the pump overrun
period.

2. During the period of pump overrun there must be an open

circuit of adequate water volume and/or load. The minimum
size of this circuit is given by the use of Graph 1.
Examples shown on Graph 1

a. For the CXSD 90/H and CXSD 100/H the minimum circuit

during pump overrun could be a load of 6 kW with a volume
of 31 litres or any other combination given by the relevant
line.

b. For the CXSD 70/H and CXSD 80/H the minimum circuit

during pump overrun could be a load of 2 kW with a volume
of 45 litres or any other combination given by the relevant
line.

The above circuit capacity during pump overrun may be
achieved either by provision of an adequate bypass circuit or
by ensuring that a zone of suitable size is open for circulation
during this period by relevant control of zone valves or pumps.

continued on page 6

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Concord CXSD/H -

Installation & Servicing

GENERAL

CLEARANCES & DIMENSIONS

Boiler Size

CXSD 40/H CXSD 50/H CXSD 60/H CXSD 70/H CXSD 80/H CXSD 90/H CXSD 100/H CXSD 110/H CXSD 120/H

Front clearance

mm (in)

750 (29

1/2

)

Rear clearance

mm (in)

150 (6)

300 (12) 300 (12) 300 (12) 300 (12)

Side clearance

mm (in)

50 (2)

100 (4)

Dimension A

m m

750

882

1042

1212

1385

1/2

3/4

1/2

Dimension B

m m

108

122

135

190

160

1/4

7/8

3/8

1/2

1/4

Dimension C

m m

931

893

5/8

3/16

Dimension D

m m

177

187

224

271

321

3/8

7/8

5/8

Dimension E

m m

116

163

213

3/4

1/8

5/8

1/2

3/8

Table 4

POSITION OF BOILER

Minimum clearances required
from walls or other fixed objects
to allow for the free access of
combustion air are shown in
Table 4 above.
However, for maintenance
purposes we suggest a
minimum rear clearance of
50mm.
Any combustible material
adjacent to the boiler and its flue
system must be so placed or
shielded as to ensure that its
temperature does not exceed 65

C (150

F).

MULTIPLE BOILER INSTALLATIONS

The minimum installation clearances must
conform to the dimensions given below:

CXSD 40/H, 50/H, 60/H, 70/H & 80/H

Clearance between boilers = 50mm
Clearance at both ends of the multiple installation = 50mm*

CXSD 90/H, 100/H, 110/H & 120/H

Clearance between boilers = 100mm
Clearance at both ends of the multiple installation = 100mm*
Rear clearance: sufficient clearance should be given at the
rear of the boiler for connection of gas and water pipework.
*Additional clearance is required for access at either end of
the installation.

100

CON5214

Example A

Example B

CXSD 1

10/H &

CXSD 120/H

CXSD 100/H & CXSD 90

CXSD 80/H & CXSD 70/H

CXSD 40/H

CXSD 60/H & CXSD 50/H

Heat Load During Pump Overrun (kW)

Water Volume in Circuit during Pump Overrun (litres)

Relationship between load and water volume for the

minimum capacity of water circuit during the 6 minute

pump overrun period for different boiler outputs.

Graph 1 - Heat Load / Water Volume

10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

190 200

160 170 180

120

110

100

90
80
70
60
50
40
30
20
10

Graph 2 - Hydraulic Resistance

Hydraulic

Resistance

(mbar)

Flow (litres/min)

C(20

-
CXSD

40/H

C(20

-
CXSD

50/H

C(20

-
CXSD

60/H

C(20

-
CXSD

70/H

C(20

-
CXSD

80/H

C(20

-
CXSD

90/H

C(20

-
CXSD

100/H

C(20

-
CXSD

1
10/H

C(20

-
CXSD

120/H

403-1

CON5215

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Concord CXSD/H -

Installation & Servicing

GENERAL

Particular reference should be made to BS. 6644: Section 2;
Subsection 10 and Guidance note PM5 "Automatically controlled
steam and hot water boilers" published by the Health and Safety
Executive.

The information and guidance given below is not intended to override
any requirements of either of the above publications or the
requirements of the local authority, gas or water undertakings.

Other British Standards applicable are BS.5422 & BS.6700.

The information provided is based on the following assumptions:

1. An independent open vent/safety pipe connection is made to

the redundant boiler flow tapping or is positioned immediately
after the system flow pipe connection to the header, as shown.

2. An independent cold feed/expansion pipe connection is made

to the redundant boiler return tapping. Cold feed/expansion pipe
connections made to the pumped system return will result in an
increase in the static head requirement, caused by the additional
resistance of the distributor tube. Surging may also increase.

3. The maximum flow rate through the boiler is based on a

temperature difference of 11°C at full boiler output and the
circulating pump is positioned in the flow to the system.

4. The boiler is at the highest point of circulation in the system.

Systems designed to rise above the boiler flow tappings will
automatically require a minimum static head higher than that
shown.

5. The position of the open vent/safety pipe above the expansion

cistern water level is given as a guide only. The final position will
depend upon the particular characteristics of the system.
Pumping over of water into the expansion cistern must be
avoided.

Note A.
This minimum height must be increased, if
necessary, to comply with the minimum head
required by the pump manufacturer in order to
avoid cavitation.
Note B.
This diagram does not show safety valves, water
flow switches, etc., necessary for the safe
operation of the system.

PUMP POSITIONS

Whenever practically possible the circulating pump(s) should be
positioned so that it pressurises the system being served. The
vertical distance between the pump(s) and any cold feed and
expansion cistern MUST comply with the pump manufacturers
requirements in order to avoid cavitation. These requirements
override the information given in Frame 3 if the static head
required for the pump(s) exceeds that required for the boiler.

MINIMUM FLOW OF WATER - Refer to Table 5

The system design must provide for an adequate flow rate
through the boiler at all times when the boiler is firing. The
minimum flow rate should correspond to a temperature
difference across the boiler flow and return of 35

C (63

F),

assessed at catalogue rating.

WATER TREATMENT FOR HOT WATER AND
HEATING BOILERS

There is a basic need to treat the water contained in all heating
and indirect water systems, particularly open vented systems. It is
assumed, incorrectly, that because boilers are operating in
conjunction with what is apparently a closed circuit an open vented
system will not, under normal circumstances, allow damage or
loss of efficiency due to hardness salts and corrosion once the
initial charge of water has been heated up a few times.

1mm of lime reduces the heat transfer from metal to water by
10%.

In practice the deposition of these salts is liable to cause noises
from the boiler body or even premature boiler failure. Corrosion
and the formation of black iron oxide sludge will ultimately result
in premature radiator failure.

Open vented systems are not completely sealed from the
atmosphere if proper venting and expansion of system water is to
be achieved. The same tank is used to fill the system with water
and it is through the cold feed pipe that system water expands
into the tank when the boiler passes heat into the system.

Table 5 - Flow rates for fully pumped systems

Boiler

Minimum flow rates for a

temperature difference of 35

C (63

l/s

g.p.m.

CXSD 40/H

0.28

3.7

CXSD 50/H

0.34

4.5

CXSD 60/H

0.41

5.4

CXSD 70/H

0.48

6.3

CXSD 80/H

0.55

7.3

CXSD 90/H

0.62

8.2

CXSD 100/H

0.68

CXSD 110/H

0.75

9.9

CXSD 120/H

0.82

10.9

3 OPEN VENTED SYSTEMS - Minimum static head requirements

The wiring diagrams in Frames 16,17 &18 illustrate the control
methods for achieving the above.

3. Pump selection should take account of the hydraulic resistance

given in Graph 2.

CON5349

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Concord CXSD/H -

Installation & Servicing

GENERAL

SEALED (PRESSURISED) SYSTEMS

Working pressure 6 bar maximum.

Particular reference should be made to BS. 6644: Section 6
Guidance note PM5 "Automatically controlled steam and hot
water boilers" published by the Health and Safety Executive.

The information and guidance given below is not intended to
override any requirements of either of the above publications or
the requirements of the local authority, gas or water undertakings.

In general, commercial closed pressurised systems are provided
with either manual or automatic water make up.

On both instances it will be necessary to fit automatic controls
intended to protect the boiler, circulating system and ancillary
equipment by shutting down the boiler plant if a potentially
hazardous situation should arise.

Examples of such situations are low water level and operating
pressure or excessive pressure within the system. Depending
on circumstances, controls will need to be either manual or

automatic reset. In the event of shutdown both visual and
audible alarms may be necessary.

Pressure vessels used must comply with BS. 4814 and must
be sized on the basis of the total system volume and initial
charge pressure.

Initial minimum charge pressure should not be less than 0.5
bar (7.2 psi) and must take account of static head and
specification of the pressurising equipment. The maximum
water temperatures permissible at the point of minimum
pressure in the system are specified in Guidance Note PM5.

When make up water is not provided automatically it will be
necessary to fit controls which shut down the plant in the event
of the maximum system pressure approaching to within 0.35
bar (5 psi) of safety valve setting.

Other British Standards applicable to commercial sealed
systems are:-

BS. 6880: Part 2.
BS. 1212
BS. 6281: Part 1
BS. 6282: Part 1
BS. 6283: Part 4

FOR SMALL PIPE INSTALLATIONS;
BS. 6891;

Installation of low pressure pipework

FOR LARGE PIPE INSTALLATIONS

Gas Installations
IGE-UP-1:

Purging Procedures of Non-domestic Gas
Installations. Soundness Testing Procedures
for Industrial and Commercial.

IGE-UP-2:

Guidance notes on the Installation of Gas
Pipework, Boosters and Compressors in
Customer's Premises Equal to or Greater
than 25mm (Non-domestic).

IGE-UP-10:

Installation of Gas Appliances in Industrial and
Commercial Premises.

BS.6644:

Installation of Gas Fired Hot Water Boilers
70kW to 1.8MW (net).

BS 6880 Pt 1-3: Water Supply.
CP342:2:

Centralised Hot Water Supply.

Model Water Bye-laws
Manufacturers notes must not be taken, in any way, as
overriding statutory obligations.

The appliance must be installed in a room separated from living
rooms and provided with appropriate ventilation direct to the outside
- see Table 6.

FOUNDATION

The boiler must stand on a non-combustible floor (i.e. concrete or
brick) which must be flat, level and of a suitable load bearing
capacity to support the weight of the boiler (when filled with water)
and any ancillary equipment.

If the boiler is mounted on a plinth then the dimensions must exceed
the plan area of the boiler by at least 75mm on each side.

Conversely, when the system cools, water previously expelled is
drawn back from the tank into the system together with a quantity
of dissolved oxygen.

Even if leakage from the heating and hot water system is
eliminated there will be evaporation losses from the surface of
the tank which, depending upon ambient temperature, may be
high enough to evaporate a large portion of the system water
capacity over a full heating season.

There will always be corrosion within a heating or hot water system
to a greater or lesser degree, irrespective of water characteristics,
unless the initial fill water from the mains is treated. Even the
water in closed systems will promote corrosion unless treated.
For the reason stated, Caradon Ideal Limited strongly recommend
that when necessary the system is thoroughly cleaned, prior to
the use of stable inhibitor, which does not require continual
topping up to combat the effects of hardness salts and corrosion
on the heat exchangers of the boiler and associated systems.

Caradon Ideal Limited advise contact directly with specialists
on water treatment such as:

Fernox Manufacturing Co. Ltd., or Sentinel Division,
Tandem House,

Betz Dearborn Ltd.,

Marlowe Way,

Widnes,

Croydon,

Cheshire, WA8 8UD

Surrey CRO 4XS

Tel. 0151 424 5351

Tel. 0870 601 5000

INSTALLATION REQUIREMENTS

The appliance must be installed by a CORGI registered installer.

The installation of the boiler must be in accordance with the
relevant requirements of the Gas Safety Regulations, current
I.E.E. (BS. 7671) Regulations, Model Water Bye-laws, local
water authority bye-laws and it should also comply with any
relevant requirements of the local gas supplier, local authority
and the relevant British Standard Codes of practice and
building regulations.

These appliances are NOT suitable for installation where they
will be exposed to the elements. A boiler room shall be
constructed or adapted to meet the requirements of BS 6644.
The maximum ambient temperature is 32

C at 1.5 metres from

the floor with a maximum humidity of 90% RH.

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Concord CXSD/H -

Installation & Servicing

GENERAL

Position ventilation grilles to avoid the risk of accidental
obstruction by blockage or flooding. If further guidance on
ventilation is required then consult BS.6644 or BS.5440:2:2000

AIR SUPPLY BY MECHANICAL VENTILATION

The supply of air by mechanical means to a space housing the
boiler should be by mechanical inlet with natural or mechanical
extraction. Mechanical extract ventilation with natural inlet must
not be used.

Where a mechanical inlet and a mechanical extract system is
applied, the design ventilation flow rates should be as in Table 4
of BS.6644.

The requirements for air supply by mechanical ventilation are given
in BS.6644.

Note. For mechanical ventilation systems an automatic control
should be provided to cause safety shutdown or lockout of the
boiler(s) in the event of failure of air flow in either inlet or extract
fans.

IMPORTANT. The use of an extractor fan in the same room as the
boiler (or in an adjacent, communicating room) can, in certain
conditions, adversely affect the safe operation of the boiler. Where
such a fan is already fitted (or if it is intended to fit an extractor fan
after installation of the appliance) the advice of the gas supplier
should be obtained.

Tests for spillage of products from the draught diverter when the
extractor fan is running and all doors and windows are shut should
be carried out after installation, If spillage is detected, the area of
permanent ventilation must be increased.

CHIMNEY SYSTEM

To ensure the safe and satisfactory operation of the boiler then
the chimney system (which may be common or individual, in the
case of twin or multiple boiler installations) must be capable of the
complete evacuation of combustion products at all times. The
effective height of the chimney terminal(s) above the boiler outlet(s)
must ensure sufficient buoyancy to overcome the resistance of
the bends, tees and runs of the flue pipe involved and shall
terminate in a down draught free zone. The number of bends and
lengths of horizontal flue pipe used should be kept to a minimum
in order to reduce gas flow resistance.

Compliance with the recommendations made in BS.6644; IGE
UP/10 Installation of Gas Appliances in Industrial and Commercial
Premises and the 'Third Edition of the 1956 Clean Air Act
Memorandum' should be strictly observed where applicable.

The chimney design should avoid the formation of excessive
quantities of condensate. For this reason it is recommended that
all chimneys are insulated and lined. In the case of brick or similar
structures a stainless steel rigid or flexible flue liner (grade 304/
316) may be used in conjunction with a 50 mm (minimum) thick
layer of vemiculite or perlite granules between the liner and the
inner skin of the chimney body. Liners should be sealed at both
top and bottom.

As the Concord CXSD/H range of boilers is supplied complete
with an integral draught diverter, a diverter MUST NOT be fitted
within the chimney system.

Drainage points positioned at the bottom of all vertical chimney
sections should be provided. Drain pipes should be no less than
25 mm I.D., manufactured from acid condensate resistant material
such as stainless steel and be positioned so that pipe runs and
discharge points are not subject to the effects of frost and that flue
gases cannot leak into the boiler room.

Care should be taken to ensure the specification of the chimney is
suitable for the application by reference to the manufacturers
literature. Caradon Ideal Limited can offer advice on the design
of suitable chimney systems.

GAS SUPPLY

If there is any doubt regarding the capacity of the gas meter, the
available gas pressure, the adequacy of existing service pipes or
the size required for new service pipes then the advice of the gas
supplier should be requested.

Installation pipework should be fitted and tested for gas soundness
in accordance with BS. 689:1 IGE-UP-1 for small installations
and IGE-UP-2 for large installations.

The local gas supplier must be consulted if it is necessary to employ
a gas pressure booster.

ELECTRICAL SUPPLY

WARNING. This appliance must be efficiently earthed.

A 230 V - 50 Hz mains supply is required, fused at 5 amps.

Wiring external to the appliance MUST be in accordance with
the I.E.E. (BS. 7671) Wiring Regulations and any local
regulations which apply.

For details of connections see Frame 14.

VENTILATION

Safe, efficient and trouble-free operation of open flued gas
boilers is vitally dependent on the provision of an adequate
supply of fresh air to the room in which the appliance is
installed. Ventilation by grilles communicating to the outside
air is required ; the minimum free area and the required
positioning of these grilles must be in accordance with Tables
6 and 7.

Table 6 - (to BS5440)
CXSD 40H-60H boilers installed in a room or internal space

Boiler size

Air vent free area cm

202

247

304

This air vent shall be direct to outside air or to a room or internal
space itself with an air vent to outside air of the same size.

Table 7 - (to BS6644)
CXSD 70H-120H boilers
Required area (cm

) per kW of total rated input (net)

Boiler room

Enclosure

Low level (inlet)

High level (outlet)

Note: Where a boiler installation is to operate in summer
months (e.g. DHW) additional ventilation requirements
are stated, if operating for more than 50% of time (refer
to BS6644).

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INSTALLATION

CASING PACK contains

Front panel ........................ 1 off

Side panel ......................... 2 off

Top panel .......................... 1 off

Flue brush ......................... 1 off

Casing hardware pack ...... 1 off

INSTALLATION HARDWARE PACK contains

M10 washer ....................................... 4 off

Split pin .............................................. 1 off

Strain relief bush ................................ 1 off

M10 x 25 Hex. Hd. screw ................... 2 off

M10 x 35 Hex. Hd. screw ................... 2 off

Gasket EPDM Type EP600 ............... 3 off

Plug 2" taper Sq. Hd .......................... 3 off

Flange RC 1" ..................................... 1 off

2" BSP Flange (distributor tube) ........ 1 off

2" Installation pipe (handling bars) .... 2 off

Thermostat pockets ........................... 2 off

1. Remove the casing carton and outer packaging frame.

2. Remove the casing pack support frame.

3. Remove the distributor tube pack, controls package and

installation pack.

4. Remove the 2" BSP steel handling bars from installation

pack.

5. Remove the 4 base bolts holding the assembly to the

packaging base.

6. Remove the wood screws securing the front cross

member on the packaging base.

7. Remove the gas cock by unscrewing the union and

screw in the handling bars into the 2 front tappings.
Protect the exposed inlet gas union from ingress of dirt.

8. Knock out front spacing blocks from the packaging base,

ensuring that the boiler assembly is supported, using 2"
BSP handling bars.

9. Using the handling bars, manoeuvre the boiler forward on

the packaging base and slide it over collapsing base on to
the floor.

Note. Before manoeuvring the boiler into its final position
see Frame 8

PACKAGING

Check that all these packages are complete and have been
correctly received on site.

Factory assembled boilers are despatched from the works as
fully packaged units comprising:

1. Assembled boiler body (with distributor tube) on a wooden

pallet base enclosed in a wooden crate.

2. Carton containing the casing, fastenings and flue brush.

3. Carton containing the installation pack.

4. Carton containing the control box and instruction books.

PACKAGING AND BOILER REMOVAL

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INSTALLATION

c. Fit the 2 thermostat pockets. Refer to Frame 9.

Note. Frame 9 shows the relationship between the
overheat thermostat and the flow tapping.

d. Complete the water connections by plugging the 2 front

top tappings with the 2" BSP plugs provided.

Position the overheat thermostat phial into the thermostat
pocket at the opposite side to the flow pipe. The illustrations
below show the rear of the boiler with the flow and relative
overheat thermostat positions.

Ensure that the overheat thermostat phial and control sensor
are correctly secured in the pockets. Refer to Frame 13.

BOILER ASSEMBLY

1. Fit the distributor tube (supplied with the boiler) into one

of the return connections. That is one of the rear lower
ports. Refer to Frame 5.

Fit the flange using the M10 x 35mm screws and
washers provided.

Ensure that the tube flange aligns horizontally and that
the 2 sealing gaskets are correctly assembled on the
tube. Refer to alignment notches in Frame 5.

2. Fit the 1" tapped flange to the other lower rear

connection using the gasket and M10 x 25mm screws
and washers provided.

3. Temporarily screw the 2 handling bars (2" pipe) into the

top tappings and manoeuvre the boiler into position.

4. Complete the system connections, using suitable

jointing compound, as follows:

a. The flow connection may be made to either of the

rear top tappings (either at the same side as the
return or opposite the return).
To avoid air locks, any reduction in pipe size must be
made in the vertical plane or achieved by using
eccentric bushes.

b. The 1" tapping in the redundant return flange may be

used for the cold feed on an open system or
connection of a pressure vessel if on a sealed
system.
If not required for this purpose it should be plugged.

SYSTEM CONNECTIONS

One flow and return connection should be made to the rear of
the boiler - either on one side or opposite sides.

The distributor tube and gaskets, supplied with the boiler,
must be connected into the pumped return connection. Refer
to Frame 8.

2 thermostat pockets are supplied in the installation pack.
These must be fitted in the 2 top

1/2

" BSP tappings at either

side of the rear of the heat exchanger.

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INSTALLATION

14 ELECTRICAL CONNECTIONS

Connection must be made in a way that allows complete
isolation of the electrical supply - such as a double pole
switch, having a 3mm (1/8") contact separation in both poles,
or a plug and socket serving only the boiler and system
controls. The means of isolation must be accessible to the
user after installation.

This should serve only the boiler, together with its controls
and pumps. The supply must be wired direct to the boiler
control box and must not be interrupted by any system
controls. The pump(s) and any system controls must be
wired back to the boiler control box.

The mains supply to the boiler must be wired into the boiler
terminals L1, N on the plug-in Mains voltage connector
shown below and in Frame 15. The earth must be wired to
the earth post as shown in Frame 13.

The control box incorporates a pump overrun device which
is necessary to dissipate residual heat after plant shutdown.
It is essential that the main pump (or shunt pump if used) is
wired to the pump terminals marked L2, N on the plug-in
Mains voltage connector shown below and in Frame 15.
The earth must be wired to the earth post as shown in Frame
13.

If no external controls are fitted, it is essential that a
link is wired in place of it on the "mains voltage
connector".

The flow switch should be connected via volt-free contacts
to the 'Flow S' terminals. A link may be fitted in place of the
flow switch but the control will not be able to analyse the
faulty flow switch, if such a failure should occur. Either of
the above must be fitted or the boiler will not operate.

Any system controls should be connected, via volt free
contacts, to the terminals marked 'EXT C'. Do NOT connect
an external clock to these contacts or any mains

voltage. If no external controls are fitted a link must be fitted
across 'EXT C' terminals.

The boiler provides frost protection via the boiler sensor. If an
external frost thermostat is required contact Caradon Ideal
Limited.

If the downdraught flue thermostat is to be fitted then the link
(marked TTB) should be removed from the plug-in connector.

The internal wiring of the boiler control box is shown in Frame
15.

Wiring should be PVC insulated cable, not less than 0.75mm

(24/0.2mm). All fuses must be ASTA approved to BS. 1362

The length of the conductors between the cord anchorage and
the terminals must be such that the current carrying conductors
become taut before the earthing conductor, if the cable or cord
slips out of the cord anchorage.

The earth connection MUST NEVER be omitted.

Wire the earths as shown in Frame 13.

All wiring between entry at the rear of the boiler and the
connection box must be secured neatly under the cable clips
provided. Wiring must never be allowed to come into contact
with any heated surfaces.

Carefully route the electrical leads from the gas valve/ spark
generator behind the LH panel return and secure with clip as
shown.

Fit the plug-in connector into the mains voltage connection box
behind the control box.

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INSTALLATION

16 ZONES WITH BI-DIRECTIONAL MOTORISED VALVES

IMPORTANT

Terminal L2 may control the appropriate
pump(s) directly, provided that the total
running or starting current does not exceed
6A (resistive or inductive): if this rating would
be exceeded, then appropriate switchgear
must be used to control the pumps indirectly.

Three zones are illustrated but the principles
may be extended as required, provided the
above conditions are met. Each relay will
then require as many contacts as there are
zones.

Overrun

Since any zone may be the load during
overrun, all zones MUST individually be able
to satisfy the conditions in the foregoing
paragraph. If not all zones can do this then
consider other means of control, detailed on
other sheets.

Normal operation

When any thermostat is satisfied while
others are calling for heat, power is available

15 INTERNAL WIRING

v violet
pk pink

y/g yellow/green
or orange

y yellow
w white

br brown
r

red

b blue
bk black

At the start of the next call for heat (or the next clock period)
valves on zones not calling for heat will motor shut.

Water circulation system - refer to page 4

via relay contacts, to close the valve for that zone. When all
thermostats are satisfied (also when the clock period ends)
all relays will be off, so the zone valves which were open will
remain open for the pump overrun period.

LEGEND

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INSTALLATION

18 ZONES WITH SPRING-RETURN MOTORISED VALVES

IMPORTANT

Terminal L2 may control the appropriate
pump(s) directly, provided that the total
running or starting current does not exceed
6A (resistive or inductive): if this rating would
be exceeded then appropriate switchgear
must be used to control the pumps indirectly.

Three zones are illustrated but the principles
may be extended as required, provided the
above conditions are met. Only one relay is
required, irrespective of the number of zones.

Overrun
During overrun and dormant periods, Zone
Valve 1 is held open. This zone, therefore,
MUST satisfy the conditions in the foregoing
paragraphs and Graph 1.

Normal operation
During a call for heat on Zone 1 only, the
boiler energises via Zone 1 thermostat and
the normally closed contacts of the relay.

During a call for heat on other zone(s), the
relay will be energised by the auxiliary switch
on the zone valves. This provides power to
energise the boiler. If, in addition, Zone 1 now
calls for heat, its thermostat will open Zone 1
valve via the normally open contacts of the
relay.

17 ZONES WITH INDIVIDUALLY PUMPED ZONES (3 zones shown)

IMPORTANT

Terminal L2 may control the appropriate
pump(s) directly, provided that the total running
or starting current does not exceed 6A
(resistive or inductive): if this rating would be
exceeded then appropriate switchgear must be
used to control the pumps indirectly.

Three zones are illustrated but the principles
may be extended as required, provided the
above conditions are met. For each zone
(except Zone 1) a relay with 2 C/O contacts is
required.

Overrun
During overrun periods, Zone 1 pump performs
the overrun facility; this zone, therefore, must
satisfy the conditions in the foregoing
paragraphs and Graph 1.

Normal operation
During a call for heat on Zone 1 only, Zone 1
thermostat energises the boiler, which in turn
energises Zone 1 pump from terminal L2.

During a call for heat on other zones the
appropriate relay directs power to L1 to
energise the boiler, at the same time ensuring
that Zone 1 pump is controlled by Zone 1
thermostat.

Water circulation system - refer to page 4

When the clock period ends, Zone valve 1 will (stay) open via
normally closed relay contacts to achieve pump overrun.

Water circulation system - refer to page 4

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INSTALLATION

19 COMMISSIONING AND TESTING

GENERAL

Check that all drain cocks are closed, that any stop valves
fitted to the flow and return pipes are open and that the
system has been filled and properly vented.

PURGING

Check that the electricity supply is switched OFF.

Remove the casing lower front panel.

Extinguish all naked lights and open all doors and windows.
DO NOT SMOKE. Check that the gas supply is turned ON at
the meter and open the main gas inlet cock. Loosen the
union and allow air to be purged from the gas line until gas is
smelled. Refer to BS 6891 or IGE-UP-1 for further details.
Retighten the union.

The CXSD/H incorporates an advanced
microprocessor based control system which
operates all electrical functions of the boiler
including automatic ignition, flame detection,
thermostatic control, and high/low burner
operation. In addition, the microprocessor also
has onboard commissioning and servicing
instructions and a fault diagnosis programme.

The next section describes the minimum
procedure to light and commission the boiler. Full
operating instructions for the microprocessor
control and details of the high/low operation
system are included in Frames 27-30.

20 INITIAL LIGHTING

1. Check that the gas and electricity supplies to the boiler are

turned OFF.

2. Connect a gas pressure gauge to the inlet pressure test

point. (Frame 23 or 24).

3. Turn on the gas and electricity supplies. The display will

initially show a start-up code followed by;

4. Press the [1/0] button The display will change to:

then change every few seconds to indicate the boiler
status. The boiler will commence its ignition sequence.

5. The boiler should light, initially at low rate for a period of

approximately 30 seconds before proceeding to maximum
rate. If the boiler fails to light, allow the controls to cycle
until ignition is established. If the boiler fails to light after 5
attempts, the display will show "Detection Fault". In this
case, the ignition sequence should be reset by pressing

TESTING FOR GAS SOUNDNESS

Close the gas supply cock at the meter.

Remove the screw in the inlet pressure test point, Frames
23/24, and connect a gas pressure gauge to the test point.
Take particular care to ensure a gas-tight connection. Open
the gas supply cock at the meter and the appliance gas
cock; record the static pressure. Next, close the gas supply
cock at the meter. Wait for 1 minute for temperature
stabilisation then observe the pressure gauge over a period
of 2 minutes.

Any leaks must be cured.

Replace all pressure test point screws.

21 LIGHTING INSTRUCTIONS

the [COPY] button. Check that the gas inlet pressure is at
least the minimum value stated in Table 2 when the boiler
is firing at maximum rate (High).

6. Whilst the boiler is warming up, observe the display to

become familiar with its operation. The display changes
automatically between the:

Boiler status and flow temperature

Hours run

Temp set

Programmer status

Enter for menu

Day

Date and time

Note. That as the boiler flow temperature approaches the
thermostat setting, the boiler is automatically reduced to low
rate.
This feature is designed to improve overall operating
efficiency and reduce short cycling under low load conditions.
The controls will automatically switch the boiler between high
and low upon demand.

Display

Up / Down buttons

On / Standby button

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INSTALLATION

22 CHECKING THE MANIFOLD PRESSURES

23 ADJUSTING THE MANIFOLD PRESSURES: CXSD 40H-90/H ONLY

5. Press the [0/1] button to turn the appliance off, then

disconnect the high/low solenoid connector plug (10)
from the gas valve. Turn the appliance on and repeat the
above sequence but using the low rate adjustment screw
(6) inside the spindle.

6. Turn the appliance off, reconnect the high/low solenoid

plug, refit the dust cover over the adjustment screws and
refit both pressure test point screws. Check for gas
soundness.

7. Press [EXIT] to leave the commissioning mode and

return to the main menu.

8. Press [EXIT] again to return to the status displays.

1. Press the [ENTER] button on the fascia panel, then press

either the [UP] or [DOWN] arrow button until the display
shows:

then press [ENTER]. The microprocessor is now in
commissioning mode. Failure to enter the Commissioning
mode will result in a fault condition being detected when
the following actions are carried out.

2. If desired, it is possible to use the onboard commissioning

instructions, using the [UP] / [DOWN] arrow buttons.
However the following paragraphs provide more detailed
instructions and are recommended until the installer is
familiar with the CXSD/H.

3. It is essential to adjust the maximum setting first.

4. Adjust the system controls to ensure that the boiler will

operate at high rate for a reasonable period, then remove
the dust cover and adjust the high rate burner pressure
setting, using a suitable spanner. Turn the maximum
adjuster (7) clockwise to increase, or anticlockwise to
decrease, the pressure. After setting to the indicated
pressure allow the boiler to operate for about 5 minutes to
stabilise then recheck the burner pressure.

6. Screw - minimum adjuster.
7. Gas rate adjuster - maximum.
8. Burner setting pressure test

point.

9. Inlet pressure test point.
10. High/low solenoid connector.

LEGEND
1. Fascia panel display.
2. Overheat thermostat

reset button.

3. Main gas inlet cock.
4. Union.
5. Gas control valve.

Turn the boiler OFF by pressing the [0/1] button and allow the
flow temperature to cool to less than 50

Connect a pressure gauge to the burner manifold test point
(Frame 23 or 24). Press the [0/1] button again to turn the
boiler ON.

The boiler will operate at low rate for approximately 1 minute
before proceeding to high rate (this will only happen if the flow
temperature is below 55

C otherwise the boiler will proceed

immediately to high rate).

Observe the burner pressures and compare them to the
values given in Table 1. If either pressure differs by more
than 10%, reset the pressures by following the procedure in
Frames 23 or 24.

Con 5235

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Con 1965

to the value given in Table 8. Unscrew the adjuster on the LH
valve until the burner pressure falls then reset it to the value
given in Table 8.
Press the [0/1] button to turn the boiler OFF. Now reset the
Low burner pressure by unscrewing and removing the lower
electrical plug from the LH gas valve and the High/Low plug
from the RH gas valve. Turn the boiler ON and, using a
screwdriver, turn the screw within the spindle on the RH valve
to set the burner pressure to the value given in Table 8.
Refit the electrical plugs, dust cover and plastic cover.
Failure to follow this procedure may result in the burner
pressure being set but the 2 gas valve governors not being
set properly.

Table 8 Manifold gas pressure settings

24 ADJUSTING THE MANIFOLD PRESSURES: CXSD 100/H-120/H ONLY

1. Press the [ENTER] button on the fascia panel, then press

either the up or down arrow button until the display shows:

then press [ENTER]. The microprocessor is now in
commissioning mode. Failure to enter the commissioning
mode will result in a fault condition being detected when the
following actions are carried out.

2. If desired, it is possible to use the onboard commissioning

instructions using the up/down arrow buttons. However the
following paragraphs provide more detailed instructions and
are recommended until the installer is familiar with the
CXSD/H.

3. It is ESSENTIAL to adjust the maximum pressure first.

CXSD 100/H boilers
The setting procedure must be done in 2 steps. The location of
the manifold pressure adjusters (11 & 12) on the gas valve is
shown below. Undo the screw holding the lower electrical plug
on the LH gas valve and pull it off. Prise off the plastic cover on
the High/Low solenoid (10) on the RH valve and, using a suitable
spanner, set the burner pressure adjuster (7) to the value given
in Table 8. Refit the electrical plug and secure with the screw.
Remove the dust cover from the adjuster (11) on the LH gas
valve and set the pressure to the value given in Table 8.
Now set the Low burner pressure by unscrewing and removing
the lower electrical plug from the LH gas valve and High/Low
plug from the RH gas valve. Using a screwdriver, turn the screw
(6) within the spindle on the RH valve to set the Low burner
pressure to the value given in Table 8.
Refit the electrical plugs and the dust and plastic covers.
Failure to follow this procedure may result in the correct burner
pressure being set but the 2 gas valve governors not working
correctly.

CXSD 110H-120H boilers
The setting procedure must be done in 2 steps.
The location of the manifold pressure adjuster on the gas
valve is shown in Frame 23. Remove the dust cover and, using
a screwdriver, screw in the adjuster on the LH gas valve nearly
fully.
Prise off the plastic cover on the High/Low solenoid on the RH
valve and, using a suitable spanner, set the burner pressure

Boiler

RH valve

LH valve

Low rate

adjustment

and Final

pressure

adjustment

- mbar

pressure

- mbar

CXSD/H 100

10.0

10.7

5.2

CXSD/H 110

11.6

11.1

5.4

CXSD/H 120

12.6

12.1

5.9

At the end of the adjustment procedure ensure that all
covers are replaced, disconnect the gas pressure gauge
and replace the blanking screw in the manifold pressure
test point.
Press [EXIT] to leave the commissioning mode and return
to the main menu.
Press [EXIT] again to return to the status displays.

LEGEND

1. Fascia panel display.
2. Overheat thermostat reset button.
3. Main gas inlet cock.
4. Union.
5. Gas control valve.
6. Screw - minimum adjuster (RH valve)
7. Gas rate adjuster - maximum (RH

valve).

8. Burner setting pressure test point.
9. Inlet pressure test point.
10. High/low solenoid connector.

11. Manifold pressure

adjuster (LH valve)

12. Manifold pressure

adjuster (RH valve)

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INSTALLATION

26 ADDITIONAL FEATURES OF THE CONTROL SYSTEM

27 DESCRIPTION AND OPERATION OF BOILER CONTROLS

ON / STANDBY [1/0] Button Turns the boiler on and to STANDBY.

WARNING. STANDBY does NOT electrically isolate the boiler.
When this switch is in the STANDBY position the display will show :-

On initial start up the boiler will indicate the hardware and software code, the boiler
type and indicate if the boiler is ON or at STANDBY. If the boiler is at STANDBY the
rotating information screens will not be in evidence.

To switch the boiler on press the On/Standby [1/0] button. The
display will show :-

This display will be retained for 5 seconds before the information
screens are displayed.

INFORMATION SCREENS
If the optional outside temperature kit, enabling weather
compensation, has been fitted the display will indicate the
compensated set point temperature.
An example of the display is as follows :-

MONDAY
14 : 10 19 / 09 / 95
ON HIGH 50 °C
HOURS RUN 250
TEMP SET 82 °C
PROGRAMMER ON
"ENTER" FOR MENU

In addition to the operational characteristics described above, the control
system incorporates the following features accessible to the user or
service engineer:

ADJUSTABLE BOILER TEMPERATURE CONTROL
This is factory preset at 82

C but may be adjusted by the user between

C and 85

C. Refer to Frame 30.

PROGRAMMER TIMER
A maximum of 3 time periods per day can be programmed in to the boiler.
Note. This a boiler timer only and does not replace a conventional
system programmer serving more than one heating zone.

OUTSIDE SENSOR (Optional extra)
If the optional outside sensor is fitted, the control system will recognise
this and automatically regulate the boiler flow temperature with respect
to changes in the external temperature. If the sensor is fitted, an
extra status information screen will appear stating whether the device
has been activated or not (i.e. compensator on/off).

COMMISSIONING INSTRUCTIONS
These are provided to assist the installer to commission the boiler.

SERVICING INSTRUCTIONS
These are provided to assist the service engineer.

FAULT DIAGNOSIS
In the unlikely event of a fault condition, the microprocessors will identify
the fault area and display a suitable message on the display.

Further to these accessible features there are other features present in
the system which the installer/service engineer should be aware of.

HOURS RUN LOG
This feature enables the installer to determine the workload of the boiler.

PUMP OVERRUN
If the flow temperature is above 75

C at the time of boiler shutdown, the

controls will maintain pump operation until the residual heat within the
appliance has been dispersed and the flow temp is below 75

ANTI-CYCLE DEVICE
On any heating system, if the heating load is very low, there is a tendency
for the boiler to cycle on and off rapidly. This is inefficient and can lead
to shortened boiler life. The high/low operating system of the CXSD/H
minimises the risk of this but, in addition, the controls prevent the boiler
from short cycling by preventing subsequent ignition within a period of
2 minutes. When active, the display will show:

On / standby button

Up / down buttons

Display

25 OPERATING INSTRUCTIONS

CXSD/H features direct burner ignition, high/low burner operation, and
a microprocessor control system.
Upon a demand for heat, the controls open the low rate gas valve and
provides a rapid spark at the ignition electrode for up to 10 seconds.
The burner will light and remain at low rate for approximately 1 minute
before proceeding to high rate (when the microprocessor opens the
remaining gas valve).
If the boiler fails to light, the gas valve is closed and there will be a delay
of 1 minute before the cycle is repeated. If, after 5 attempts the burner
has failed to light, the boiler will go to lockout and 'detection fault' will be
displayed on the screen:-

When the boiler flow temperature reaches the thermostat set point, the
controls will turn the burner to low rate. If the flow temperature continues
to rise the burner will be turned off at 3

C above the set point.

If however the temperature falls below the set point whilst on low fire,
the controls will automatically turn the burner back up to maximum rate.
This system has the advantages of ensuring that the boiler accurately
maintains the set temperature (without the large temperature swings
that can be associated with on/off boilers), prevents rapid or short cycling,
and provides more efficient system operation.

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INSTALLATION

29 DESCRIPTION AND OPERATION OF BOILER CONTROLS - continued

MENU

To access the menu screen ensure that the information
screens are being displayed.
Any key, except the [1/0] button, may now be pressed to
access this feature but, as indicated on the information screen,
the [ENTER] button is the preferred means.

On entering this option the first screen displayed will be:-

The [DOWN] button can be pressed consecutively to access
the features required, which are as follows:-

If the weather compensation option is fitted then a further
screen will be displayed after commissioning.

The [UP] button will access the above options in reverse.
When the option required is displayed and the [ENTER] button
pressed another set of menus will be available as discussed
on the following pages.

PROGRAMMER TIMER

The programmer has 3 time zones per day for each day of the
week. Each day can be programmed for the requirements of
that day, giving 7 programmed days, or, using the [COPY]
facility, any number of days can be the same. If a particular
time zone is not required then the ON and OFF periods should
be programmed for the same time.

Each button has an auto repeat function.

The programmer is based on a 24 hour clock and the boiler
comes with a backup programme set for :-

All Day

The boiler will respond to this programme unless an alternative
is programmed in.

Using the [UP] or [DOWN] button select the "Programmer
Timer" from the menu and press [ENTER]. The following
menus will be available using the [UP] or [DOWN] buttons:-

To select any of the above use the [UP] or [DOWN] button
until the option required is displayed and press [ENTER].

STATUS

Enables the selection of programme hours, all day usage or
24 hour.

If the "Programme Hours" option is selected the boiler will go
on and off subject to the times programmed.

If ALL DAY usage is selected the boiler will come on at the first
"ON" period selected and off on the last "OFF" period
selected, ignoring all other time settings. Based on the above
backup programme this means the boiler would run, subject to
any other external controls, from 07:30 to 22:00 hours.

If 24 HOUR is selected the programme times will be ignored
and the boiler will run subject to the external controls until one
of the other options is again selected.

SET TIME/DATE

Enables the correct time and date to be entered.

The display will show a flashing day of the week as follows :-

The correct day can be selected by use of the [UP] or [Down]
button and when correct the [ENTER] button should be
pressed. The time and date will now be displayed as follows:-

with, first, 2 digits, the hours, flashing.

By use of the [UP] or [Down] button the correct hour is
selected and the [ENTER] button pressed. The minutes will
now be flashing and, by use of the [UP] or [DOWN] button, the
correct minutes selected and the [ENTER] button pressed.

This method is repeated until the correct day, month and year
are selected. On selecting the correct year and pressing
[ENTER] the hours will flash then, if all the data is correct, the
[EXIT] button should be pressed for the control to accept this
information.

ADVANCE

Enables the programme to be advanced by 1 hour.

The following display will be available:-

If the [YES] button is pressed and the programmer is in an
OFF period the boiler will be brought on for 1 hour, subject to
external controls. If the boiler is on with less than 1 hour to a
programmed off period then the difference between this time
and 1 hour is the time of the extended on period. If the boiler
is in the 24 hour mode then this option will have no effect.

If this advance has been selected, to cancel it then the same

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INSTALLATION

30 DESCRIPTION AND OPERATION OF BOILER CONTROLS - continued

Delayed High Rate Gas valve Operation
When the boiler is started from cold the high rate gas valve
will be delayed for 3 minutes and then energised. If the boiler
flow temperature is equal to or greater than 55

C then this

delay will NOT occur.

Notes.

1. If a fault occurs with the boiler thermostat the fault

display screen will show "C/H Sensor Fault".

2. When the low rate gas valve is de-energised as the

temperature required has been obtained the boiler will
go into an anti-cycle route for 2 minutes. The display will
indicate anti-cycle and the current flow temperature.

SERVICING

The SERVICE option is intended as a memory aid to the more
comprehensive servicing instructions to be found in this
manual.

Using the [UP] or [Down] button select SERVICE from the menu
and press [ENTER]. The following display will be available:-

The 2 screens will alternate to display this whole message.
When using this option, arrow keys will be in evidence to
indicate if the UP or DOWN buttons should be used. It is
IMPORTANT that these instructions are carried out precisely
and in the order displayed.

COMMISSIONING

The "Commissioning" option is intended as a memory aid to
the more comprehensive commissioning instructions to be
found in this manual.

Using the [UP] or [Down] button select "Commissioning" from
the menu and press [ENTER]. The following display will be
available:-

The 2 screens will alternate to display this whole message.

When using this option arrow keys will be in evidence to
indicate if the [UP] or [DOWN] buttons should be used. It is
IMPORTANT that these instructions are carried out precisely
and in the order displayed.

FAULT DIAGNOSIS

In the unlikely event of a fault condition, the microprocessors
will identify the fault area and display a message indicating the
nature of the fault, to assist a speedy and effective repair.

See "Fault Finding" section for more details.

procedure should be followed but the [NO] button pressed.

PROGRAMME HOURS

Enables a user-timed programme to be entered.

The following display will be available:-

with the hours, 06, flashing

Using the [UP] or [DOWN] button select the correct hour and
press [ENTER]. The minutes will now flash and the correct
minutes should be selected, using the [UP] or [DOWN] button
followed by pressing [ENTER]. This will cause the hours to
flash and if the correct ON time has been entered the [EXIT]
button should be pressed. The display will now show the OFF
for time zone one.

This procedure should be repeated for all 3 time zones for
Monday.

After the last [EXIT] the display will ask if this day's programmes
require to be copied to Tuesday. If the [YES] button is pressed
Tuesday's programme will be the same as Monday. This action
can be repeated for all the days or as many as required,

If the [NO] button is pressed then all 3 time slots will need to be
programmed with the required times.

TEMPERATURE SET POINT

Enables the temperature at which the boiler is required to
operate to be set. It has a range of 60

C - 85

Using the [UP] or [Down] button select the TEMP SET from the
menu and press [ENTER]. The following will be displayed:-

with the temperature flashing

The [UP] and [Down] button should be pressed until the
correct temperature is selected then the [ENTER] button
should be pressed; the temperature selected will become
stationary. Pressing the [EXIT] button will ensure that the
control accepts the new setting and return to the menu.

High / Low Operation
In the example above, when the boiler flow temperature is
equal to 82

C the high rate gas valve will close, allowing the

boiler to run at low rate. When the flow temperature exceeds
the set temperature by 3

C, in the example above 85

C, the

low rate gas valve will close and the boiler will be off. The
information screen will display

The boiler will remain OFF for a minimum of 3 minutes or until
the boiler flow temperature has dropped by 3

C, whichever is

the greater time.

If the boiler load is such that it cycles between high and low
operation the boiler will fall through 3

before the high rate gas

valve is energised.

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Installation & Servicing

SERVICING

Check that the main burner responds correctly to manual on/off
operations of any controls fitted in the gas control circuit.

Check, in the following manner, the operation of the flame failure safety
device.

1. Extinguish the main burner by turning off the main gas inlet cock.

Refer to Frames 23 & 24.

2. Check that the display shows [DETECTION LOCKOUT].
3. Turn on the gas cock and reset by pressing [COPY].
4. Fit the lower casing front panel.

5. Complete the commissioning section of the boiler log book.
6. Important Commissioning / Operating Instructions:

Do not operate this appliance for long periods or take any combustion
readings with the casing or any part of the casing removed.

ROUTINE OPERATION

Full instructions covering routine lighting and operation of the boiler are
given on the Lighting and Operation Instruction Label located on the inside
of the casing door.
Draw the attention of the boiler owner or his representative to the Lighting
and Operating Instruction Label on the inside of the casing door. Give a
practical demonstration of the lighting and shutting down of the boiler.
Describe the function of the boiler and system controls and show how they
are adjusted and used.
Describe the function of the downdraught thermostat if fitted.
Hand these Installation and Servicing Instructions, User's Instructions
and Log Book to the customer and request him to keep it in a safe place
for ready reference.
IMPORTANT. Point out to the owner that the boiler must have regular
maintenance and cleaning, at least annually, in order to ensure reliable
and efficient operation. Regular attention will also prolong the life of the
boiler and should preferably be performed at the end of the heating
season.
After servicing complete the service section of the log book and return to
the owner or their representative.
Recommend that a contract for this work should be made with a CORGI
registered engineer.

35 SERVICING

Caradon Ideal Limited does not accept any liability
resulting from the use of unauthorised parts or the repair
and servicing of appliances not carried out in accordance
with the Company's recommendations and specifications.

A comprehensive service should be carried out at least
once a year. The User is advised to make a contract with a
CORGI registered engineer.

WARNING. ALWAYS turn OFF the gas supply at the gas
cock and switch OFF and disconnect the electricity supply
to the appliance BEFORE SERVICING OR REPLACING
ANY COMPONENTS.

CLEANING THE BOILER

Pull and lift off the lower front panel and top panel from the
boiler casing.

32 TESTING

31 SPILLAGE CHECK

Check there is no spillage of
combustion products from the boiler
draught diverter by carrying out a
spillage test, as detailed in BS. 5440:1.

When commissioning the heating/domestic
hot water system the shunt pump must be
adjusted to give the minimum flow rate given
in Table 3, when that part of the system
intended to be used for dissipation of
residual heat only is in operation.

33 ADJUSTMENT OF WATER

FLOW RATE THROUGH
THE BOILER

34 HANDING OVER

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SERVICING

36 SERVICING - continued

Unscrew the extended nuts at the top of the NOx duct behind
the control box and lift the NOx duct clear of the burners, as
illustrated below.

Undo the wing nuts securing the burner front plate. Pull the

front plate forwards, at the top, and lift it out, taking care not to
damage the insulation or the detection electrode.

On the CXSD 40/H, 50/H & 60/H remove the screws holding
the HT heat shield from the LH leg of the combustion

chamber. Raise slightly and withdraw the heat shield, taking

care not to damage the leads.

The burners may be lifted out after they have been pushed

back to clear the injectors. Take care not to damage the

ignition electrode assembly and carefully detach the ignition
leads when removing the left hand burner. Take care not to

damage the detection electrode when removing the RH

burner.

GENERAL

WARNING

ALWAYS turn OFF the gas supply at the gas inlet
cock and DISCONNECT the electricity supply
BEFORE WORKING on the APPLIANCE.

To facilitate the replacement of components, remove
and replace the lower front panel, NOx duct and the
burner front plate as necessary - described under
`Servicing'.

In particular, check that:

1. The ignition electrode shield and base fixing screws are

tight.

2. The electrodes are correctly positioned. Refer to

Frames 40 or 41.

3. Reassemble in reverse order. Refit the cleanout cover,

NOx duct, and casing panels.
(CXSD 120/H boiler only)
Refit collector hood baffles within collector hood using
M5 securing screws.

TESTING AFTER SERVICING

After re-assembly, restore the electricity and gas supplies.
Light the boiler. Refer to the Lighting Instructions and also
Frame 19 `Testing for Gas Soundness' .

Check burner manifold pressures (Frame 22) and adjust if
necessary (Frames 23 or 24).

Finally, reset any external controls to the desired position.

Undo the screws securing the cleanout cover and

lift it off to give access to the flueways.

(CXSD 120/H boiler only)
Remove four M5 securing screws retaining

internal turning baffles from side of collector hood.

Slide turning baffles to rear of collector hood void
to facilitate access to flue ways for cleaning.

Remove all loose deposits from the heat

exchanger (especially from between the fins),
using the brush provided, and remove all debris

from the combustion chamber floor.

Examine the burner assembly. Clean the burner

bars by brushing them down with a stiff bristle (not

wire) brush. Check each bar carefully to ensure
that all flame ports are clear, that there are no

cracks and that all surfaces are free from

accumulated deposits.

If available, an industrial vacuum cleaner may be

useful to assist in this work. When cleaning the

burner bars, take care to avoid damage from
rough handling to the ignition or detection

electrodes.

Inspect the ignition and detection electrodes.

Ensure that they are clean and in good condition.

37 REPLACEMENT OF COMPONENTS - Refer to Frame 5

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SERVICING

PTP

CON1960

LEGEND

1. Main gas inlet cock.
2. Gas inlet union.
3. Gas control valve.
4. 'O' ring seal.
5. Spark generator.

38 GAS CONTROL VALVE

40 BURNER AND CONTROLS ASSEMBLY - Exploded View - CXSD 40/H - 90/H

39 MAIN BURNER

1. Disconnect the electrical connections to the faulty gas

valve.

2. Turn the gas inlet cock OFF and unscrew the 4 screws

on the outlet flange and then unscrew the 4 screws on
the inlet flange.
CXSD 90/H -120/H only. Loosen the other 4 screws on
the inlet flange securing the other gas valve.

3. Fit the new valve and reassemble in the reverse order,

ensuring that the arrow on the back of the valve points in
the direction of the gas flow and that new 'O' ring seals
are correctly placed in each flange connection.

4. Test for gas soundness.

5. Recommission the appliance and set the manifold

pressures as described in Frames 22 and 23 or 24.

1. Remove the NOx duct and burner front plate, as

previously described in Frame 35 and 36.

2. On the CXSD 40/H, 50/H & 60/H remove the screws

holding the HT heat shield from the LH leg of the
combustion chamber. Raise slightly and withdraw the
heat shield, taking care not to damage the leads.

3. Each burner can be removed by sliding back, to clear

the injector, then lifting out. Disconnect the ignition
leads from the LH burner and the detection lead from
the RH burner.

4. Remove the 2 screws securing the electrode assembly

and heat shield to the LH burner bracket and the 2
screws securing the detection electrode bracket to the
RH burner.

5. Reassemble in reverse order.

IMPORTANT. Care must be taken to prevent damage to the
combustion chamber insulation when replacing burners.

6. Burner manifold.
7. Main injector, 3 off.
8. Main burner (centre/RH), 2 off.
9. Main burner (LH), 1 off.
10. Ignition electrodes.

11. Overheat thermostat mounting bracket.
12. Overheat thermostat.
13. Detection electrode assembly.
14. HT leads heat shield.
15. Gas pipe.
PTP

Pressure test point.

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Installation & Servicing

SERVICING

Con 1959

41 BURNER AND CONTROLS ASSEMBLY - Exploded View - CXSD 100/H - 120/H

LEGEND
1.

Main gas inlet cock.

Gas inlet union.

'O' ring seals.

Gas control valve

Spark generator

Burner manifold.

Main injector, 3 off.

Main (centre / RH) burner, 2 off.

10. Main (LH) burner, 1 off.
11. Ignition electrodes.
12. Overheat thermostat mounting bracket.
13. Overheat thermostat.
14. Detection electrode assembly.
PTP Pressure test point

42 OVERHEAT THERMOSTAT

1. Remove the split pin from the overheat thermostat

pocket and remove the phial.

2. Unclip the capillary from its clips on the casing

side panel.

3. Loosen the 2 x M3 screws and remove the

thermostat assembly from its fixing bracket.

4. Undo the screw and remove the cover.

5. Remove the wires.

6. Undo the backnut and remove the thermostat.

7. Fit the new thermostat and secure with the

backnut.

8. Reconnect the wires as follows:

1. Pink

2. White

3. Red

Reconnect the earth terminal

9. Reassemble in reverse order.

Overheat
thermostat

Reset
button

CON5232

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SERVICING

43 CONTROL BOX - Basic Boiler, Exploded View

5. Back panel.
6. Controls box.
7. Printed circuit board 'No. 35'.
8. Ribbon cable.

LEGEND
1. Wiring clamp.
2. Connection box plug.
3. Connection box.
4. Printed circuit board 'No. 34'.

9. Printed circuit board No. RTC/34.
10. EMC Filter
11.Controls box fascia (not shown).

45 PC BOARD `NO. 34'

44 CONTROL SENSOR

1. Remove the casing top panel.
2. Remove the sensor from the thermostat pocket in the

rear heat exchanger section by removing the Heyco
bush.

3. Trace the lead back to the connector box behind the

control box. Release the connector box plug (Frame
43).

4. Replace the sensor and reassemble in reverse order.

Ensure that the lead is rerouted along the casing in the
clips provided, and check that the sensor is correctly
fitted and secured in the thermostat pocket.

1. Remove the lower front panel.

2. Undo the 2 screws securing the control box front panel.

Carefully lift it up and lower it.

3. Release the ribbon cable from PCB No. 34 by pushing the

retaining tabs sideways.

4. Release all plug connections from the board.

5. Remove the real time clock board (PCB No. RTC/34) from

PCB No. 34 by squeezing the 4 mounting pins and pulling
forwards.

6. Release PCB No. 34 from the 9 plastic mounting pins and

replace the board.

7. Re-assemble in reverse order.

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SERVICING

46 PC BOARD NO. 35

1. Remove the lower front panel.

2. Undo the 2 screws securing the control box front panel.

Carefully lift it up and lower it.

3. Release the ribbon cable plug from PCB No. 35.

4. Release PCB No.35 from the 6 plastic mounting pins

and replace the board.

5. Re-assemble in reverse order.

1. Remove the lower front panel.

2. Undo the 2 screws securing the control box front panel.

Carefully lift it up and lower it.

3. Remove the real time clock board (PCB No. RTC/34)

from PCB No. 34 by squeezing the 4 mounting pins and
pulling forwards.

4. Re-assemble in reverse order.

47 PC BOARD NO. RTC/34

48 COMBUSTION CHAMBER INSULATION REPLACEMENT

The insulation boards used in the combustion
chambers of these products contain man-made fibres,
refractory fillers, organic and inorganic binders and as
such are deemed to be harmless to humans.

Caradon Ideal Limited, however, recommend that for
your own comfort and to comply with good working
practise the procedure described below is followed.

IMPORTANT.Turn OFF the gas and DISCONNECT the
electricity supply.

To replace the insulation boards the major boiler
components (including the heat exchanger and burners)
have to be removed to gain access to the combustion
chamber.

Prior to removal of the boards the
following protective equipment should be
worn:

· Face mask supplied with the spare part.

· Gloves supplied with the spare part.

1 Damp down the combustion chamber area containing

the insulation boards.

2. Remove the insulation boards. The replacement boards

are supplied in a plastic bag. This bag should be
retained and the discarded boards should now be
placed into it.

3. Sweep any dampened particles and place in the plastic

bag.

4. Fit new insulation boards.

5. Remove the gloves and face mask and place them in

the plastic bag.

6. Wash your hands and any areas of skin which may

have come into contact with any of the particles from
the insulation board.

7. Seal the plastic bag and dispose of it and its contents

into a commercial tip.

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SITE ASSEMBLY

49 INSTRUCTIONS FOR SITE ASSEMBLED BOILERS

Legend
1. Cleanout cover.
2. Collector hood.
3. Middle section.
4. Section alignment

rings & 'O' rings.

5. End section.
6. Gas cock.
7. Drain cock.
8. NOx duct.
9. Front plate.

10. Burner manifold assy.
11. Base plate.
12. Combustion chamber.
13. Section bolt.
14. Distribution tube.
15. Tie rods.
16. Thermostat pocket.
17. Spillage skirt.
18. Gas pipe.

The site assembled boiler is supplied in the following
packages:

! Combustion chamber / manifold / burner assembly.

! Platework package.

! Casing package.

! Controls box package and instruction books.

! End and centre sections.

GENERAL

The installation of the boiler must be in accordance with the
Gas Safety (Installation and Use) Regulations 1994,
amendments 1996 or rules in force, building regulations, I.E.E.
(BS.7671) regulations and the bye-laws of the local water
undertaking. It should also be in accordance with the relevant
British Standard Codes of Practice together with any relevant
requirements of the local gas supplier and local authority.

TOOLS REQUIRED

! Spanners
! Torque wrench
! Pozi screwdriver
! Mallet

ASSEMBLY

The combustion chamber should be positioned as near as
possible to the installation site.

IMPORTANT. It must be remembered that the boiler
distribution tube has to be fitted into the rear return tapping
of the assembled boiler before siting.

Prior to assembling the sections it will be necessary to
remove the burner and controls assembly from the
combustion chamber.

Remove the assembly as follows:

1. Undo the 4 wing nuts securing the burner front plate.

Pull the front plate forwards from the top and lift it out.

2. On the CXSD 40/H 50/H & 60/H remove the screws

holding the HT heat shield from the LH leg of the
combustion chamber. Raise slightly and withdraw the
heat shield, taking care not to damage the leads.

3. The burners may now be lifted out after they have been

pushed back to clear the injector.

4. Disconnect the electrode leads and take care not to

damage the electrode assemblies.

5. Undo the nut securing the manifold assembly to the

combustion chamber, pull the manifold assembly to the
right and lift out.

Con 1855

Alignment notches

Distribution tube detail

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SITE ASSEMBLY

PREPARATION OF SECTIONS

Each section should be brushed clean on all external
surfaces and any debris which may have accumulated within
the section should be removed via the bottom ports.

Section assembly - Refer to exploded view

6. Take the back section (with 1/2" BSP. tappings in the top)

and lift it onto the combustion chamber so that the
combustion chamber back panel return is inside the
section rear lip. Locate a slotted steel ring and an `O' ring
seal into each of the 4 ports. It will be necessary to
squeeze the steel ring slightly to enable it to be pushed
fully into the recess.

7. Lift a middle section onto the combustion chamber and

carefully offer it up to the back section until it engages the
projecting steel rings. It may be necessary to use a mallet
and hardwood block to ensure that the steel rings are
pushed fully into the recesses and that the sections are
butted up to each other.
Note. Until the final section is fitted and the tie rods
fastened, the sections in the assembly are not fixed
together therefore CARE MUST BE TAKEN TO PREVENT
the installed section coming apart.

8. Repeat the above procedure for all of the remaining

sections until the assembly is complete.

9. Fit the 4 tie rods through the holes in the sides of the end

sections and fit a flat steel washer, a shakeproof washer
and a nut to both ends of each tie rod. Screw up all the
nuts equally, in turn, and finally tighten them to a torque of
38-41 Nm (28-30 lb ft).

10. Fit the distributor tube assembly as described in Frame 8.

Fit the drain cock (refer to exploded view, Frame 49).

11. On open vented systems a hydraulic test should be carried

out at 1 1/2 times the design pressure given in Table 2 for
a period of 30 minutes.

12. On a pressurised system the test should be at twice the

design pressure for a period of 30 minutes.

13. Fit the 4 coach bolts into the lugs at the bottom of the front

and rear sections. Secure with the nuts and washers
provided.

14. Fit insulation wrap around heat exchanger. Secure with

clips provided.

15. Fit the collector hood. Ensure the underside returns

running across the hood sit within the front and rear section
flueways. Fasten down using the four M6 screws and nuts
provided, through the front and rear fixing points.

16. Locate the fibreglass rope in rear section grooves to form a

seal with the spillage skirts. Fit the spillage skirts onto the
collector hood, using the self tapping screws provided.

17. Refit the manifold assembly. Position the boiler insulation

over the gas line tie bracket. Fasten the bolt securing the
bracket to the front section before wrapping and securing
insulation around the boiler body.

50 INSTRUCTIONS FOR SITE ASSEMBLED BOILERS - continued

18. Insert the burner rear

supports into the slots
at the back of the
combustion chamber.
Lift the front of the
burners over the
injectors and pull
forward to engage.

19. Fit the support angles (contained in the platework

package) to the collector hood. The angle with the hole for
the earth screw fits to the front.

20. Fit the gas inlet pipe bracket to the rear support angle on

the LH side using the self tapping screws.

21. Fit the gas inlet pipe and make good the union between

the gas cock and the valve inlet pipe.

22. Fit the Nox duct using the reverse procedure to that shown

in Frame 36 and secure with the extended nuts.

23. The boiler is now ready for installation. Go to Frame 8 and

continue the installation from there.

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FAULT FINDING

FAUL

T FINDING FAUL

T FINDING

WARNING

The ON/STANDBY [1/0] button does NOT electrically
isolate the boiler.

Before attempting any electrical fault finding ALWAYS carry
out the preliminary electrical system checks as detailed in the
Instructions for the British Gas Multimeter or other similar
commercially available meter.

The preliminary electrical system checks are the FIRST
electrical checks to be carried out during a fault finding
procedure.

On completion of any service/fault finding task which has
required the breaking and remaking of electrical connections
the following checks MUST be repeated:

a. Earth continuity

b. Polarity

c. Resistance to earth

Detailed instructions on the replacement of faulty components
are contained in the 'Servicing' section of these Installation &
Servicing Instructions.

GENERAL INFORMATION

If a flow switch is not connected to the boiler a link should be
fitted between the 2 terminals for the flow switch. If the
terminals are left disconnected the display will indicate "No
flow" and the boiler will not operate.

Anti-cycle will be in operation each time the boiler thermostat
is satisfied and a rapid demand for heat is required. The same
situation will occur if the external controls operate rapidly. This
feature reduces component wear and ensures continuous
troublefree operation. The Anti-cycle duration is 1-3 minutes.

If the system pump, with a maximum current of 3A, is
connected to the boiler pump terminals, pump overrun will be
in operation if the flow temperature is greater than 75

C, when

the heat demand is satisfied, and will continue to run until the
boiler flow is less than 75

C. If the flow temperature is less

than 75

C, when the demand for heat is satisfied, then the

pump will cease to operate.

Frost protection is inbuilt with the boiler. If the flow temperature
falls to approximately 3

C then the boiler will operate until the

flow temperature exceeds 4

C. If an external frost thermostat

is required the internal programmer should be set to 24 hours
under the programme status menu and an external
programmer and frost thermostat wired and connected to the
volt free external control terminals on the boiler.

There is an option kit available with 2 sets of volt free contacts.
One set of volt free contacts is for "Lockout" and "Overheat"
combined and one set of volt free contacts is for "Boiler run".

There is an option kit available to enable temperature
compensation to be used. The outside temperature adjusts the
boiler flow temperature to satisfy the heating load and ensure
efficient boiler operation.

The gas valves operate on High/Low and Off principle. At
start up, with the flow temperature less than 55

C the boiler

will start at low rate and after 1-3 minutes the high rate gas
valve will open. On reaching the set point, determined by the
user, the boiler will go to low rate and when the temperature

51 BOILER CONTROL

reaches the set point plus 3

C the low rate gas valve will

close. When the temperature falls 2

C the boiler will start at

low rate and remain there until the temperature falls to the set
point less 2

C then the high rate gas valve will operate.

On start up the high rate gas valve will operate immediately
after detection if the boiler flow rate is greater than 55

In order to determine the continued correct operation of the
control every 4 hours the boiler will shut down for a maximum
of 30 seconds to do a self check operation and restart
automatically.

The control will display the number of operational hours of the
boiler to the nearest hour and cannot be reset.

The boiler thermostat has a range of 60

C-80

C, in 1

steps, with an accuracy of ± 2

C and hysteresis of 3

The full sequence control enables 5 attempts at ignition, with
one minute intervals between attempts, followed by
nonvolatile lockout if detection does not take place.

If the [0/1] switch on the front panel is at "Standby.....0" then
the pump will continue to run indefinitely. In this state the frost
protection can not operate.

In "Lockout" the pump will continue to run only if the
temperature is greater than 75

C. If it is less then the pump

will be off.

FAULT FINDING

The boiler control has a unique fault diagnostic feature which
can, in the unlikely event of a failure, display a message
indicating the nature of the fault to assist a speedy and
effective repair.

The faults that are diagnosed are overheat thermostat, pump,
boiler sensor, gas valve(s), air pressure switch (if fitted), fan
(if fitted), float switch (if fitted), outside sensor (if fitted) with
indication of combustion lockout.

In the unlikely event of a fault the display will indicate
precisely the fault and give a step by step indication of the
method of correcting the fault.

If the HT generator should cease to function it is impossible to
automatically display this condition. Should this fault occur
then:-

would be displayed and the subsequent display screens
would direct attention to the spark generator.

Should a gas valve fail the diagnostics will indicate that it is
valve 1 or 2 that is at fault. If the boiler has a gas line of 2
double solenoids the diagnostics will indicate which solenoid
of the double solenoid is at fault.

The last fault instruction will be retained.

FAULT CODES

Fault codes numbered 1 to 24 are displayed where
applicable. In this event contact Caradon Ideal Limited.

157292-3.pmd

11/3/2005, 9:28 AM

Concord CXSD/H -

Installation & Servicing

FAULT FINDING

FAUL

T FINDING FAUL

T FINDING

53 FAULT FINDING FLOW CHART

Change outside

sensor.

Press [Copy]

GAS VALVE

FAULT

BOILER

SENSOR

FAULT

OVERHEAT

FAULT

OUTSIDE

SENSOR

FAULT

Check pump

connections.

Press [Copy]

Press O/H reset

button.

Press [Copy]

Check wiring.

Press [Copy]

Check water

flow.

Press [Copy]

Replace o/h stat.

Press [Copy]

Check system.

Press [Copy]

Refer to
screens

STANDBY

BURNER

LOCK OUT

Check HT leads

and electrode

positions

Check wiring
to generator.
Press [Copy]

Replace

generator.

Press [Copy]

Change pump.

Press [Copy]

Refer to screens

Check wiring.

Press [Copy]

PUMP FAULT

R
E
F
E
R

T
O

I
D
E
A
L

B
O
I
L
E
R
S

Is there a

spark ?

DOWNDRAUGHT

FAULT

Check flue

system.

Wait 15 mins.

Does boiler

fire ?

Replace

TTB.

Refer to
screens

Check gas

pressure.

Press [Copy]

Check
wiring.

Press [Copy]

Replace faulty

solenoid.

Press [Copy]

Refer to
screens

Change

gas valve

solenoid.

Press

[Copy]

Observe the display. Take actions as

follows, depending upon the display:

Check system.

Press [Copy]

Replace sensor

Press [Copy]

Check gas.

Press [Copy]

Press

[Copy]

Check

gas

valve

wiring.

Press

[Copy]

Check

detection

probe.

Press

[Copy]

YES

Replace

detection

probe

Boiler will not light

Do any external

controls call for

heat ?

Is 230V ± 10%

available at
appliance ?

Reset timer or

status as

appropriate

Reset external

controls as

appropriate

Carry out electrical

checks.

Check all fuses.

YES

Check boiler

programme timer and

status, as described

in Frame 28.

Does programme

timer require heat ?

Press [O/1] button

157292-3.pmd

11/3/2005, 9:28 AM

Concord CXSD/H -

Installation & Servicing

SHORT LIST OF PARTS

Key No.

Description

Qty.

Product No.

12.4

Boiler body insulation ........................................................... CXSD 40/H

150 093

.............................................................................................. CXSD 50/60/H

150 094

.............................................................................................. CXSD 70/80/H

150 095

.............................................................................................. CXSD 90/100/H

150 096

.............................................................................................. CXSD 110/120/H

154 856

LH Main burner ................................... Worgas 0.087.751 CXSD 40/H

150 153

............................................................ Worgas 0.087.753 CXSD 50/60/H

150 154

............................................................ Worgas 0.087.755 CXSD 70/80/H

150 155

............................................................ Worgas 0.087.757 CXSD 90/100/H

150 156

............................................................ Worgas 0.087.761 CXSD 110/120/H

154 812

Centre and RH main burners ............. Worgas 0.087.750 CXSD 40/H

150 149

............................................................ Worgas 0.087.752 CXSD 50/60/H

150 150

............................................................ Worgas 0.087.754 CXSD 70/80/H

150 151

............................................................ Worgas 0.087.756 CXSD 90/100/H

150 152

............................................................ Worgas 0.087.760 CXSD 110/120/H

154 811

Main burner injectors .......................... Size 3.4 mm;

CXSD 40/H

111 323

............................................................ Size 3.82mm;

CXSD 50/H

111 324

............................................................ Size 4.12mm;

CXSD 60/H

111 325

............................................................ Size 4.57mm;

CXSD 70/H

111 326

............................................................ Size 4.86mm;

CXSD 80/H

111 327

............................................................ Size 5.2mm;

CXSD 90/H

111 328

............................................................ Size 5.3mm;

CXSD100/H

111 329

............................................................ Size 5.5mm;

CXSD110/H

157 904

............................................................ Size 5.6mm;

CXSD120/H

154 840

Gas control valves
HONEYWELL VR4605PB 2003 ............................................ CXSD 40 -120/H

111 867

HONEYWELL VR4605AB 1019 ............................................ CXSD 100 - 120/H

111 869

29.7

Gas control valve plug and lead assemblies ...................... CXSD 40 - 120/H

111 870

.............................................................................................. CXSD 40 - 120/H

154 734

29.6

.............................................................................................. CXSD 100 - 120/H

112 431

29.5

.............................................................................................. CXSD 100 - 120/H

139 269

Ignition electrode BE/3417/SI .............................................................................

112 365

Flame detector electrode BE/3459/SI ................................................................

112 364

Spark generator assembly .................................................................................

112 721

Flame detector lead ............................................................................................

112 448

Electronic thermostat sensor and lead assembly .............................................

112 289

Overheat thermostat ...........................................................................................

155 791

Control box assembly - complete ......................................................................

154 328

PCB 34 ...............................................................................................................

069 957

PCB 35 ...............................................................................................................

069 960

Real time clock ...................................................................................................

069 958

Ribbon cable .......................................................................................................

069 961

When ordering spare parts please quote:

1. Boiler model
2. Boiler serial no. (refer to data plate on the combustion chamber)
3. Boiler B.G. P.I. No. (refer to the data plate on the combustion chamber)
4. Description
5. Quantity
6. Product no.

The following are parts commonly
required as replacements due to
damage or expendability. Their failure
or absence is likely to affect the safety
and/or performance of this appliance.

157292-3.pmd

11/3/2005, 9:31 AM

RH casing side panel ................................................ CXSD 40/H

111 650

................................................................................... CXSD 50/60/H

111 651

................................................................................... CXSD 70/80/H

111 652

................................................................................... CXSD 90/100/H

111 653

................................................................................... CXSD 110/120/H

154 898

LH casing side panel ................................................ CXSD 40/H

111 650

................................................................................... CXSD 50/60/H

111 651

................................................................................... CXSD 70/80/H

111 652

................................................................................... CXSD 90/100/H

111 653

................................................................................... CXSD 110/120/H

154 898

Casing top panel ....................................................... CXSD 40/H

111 293

................................................................................... CXSD 50/H

111 294

................................................................................... CXSD 60/H

111 295

................................................................................... CXSD 70/H

111 296

................................................................................... CXSD 80/H

111 297

................................................................................... CXSD 90/100/H

111 298

................................................................................... CXSD 110/120/H

154 897

Casing lower front panel - complete with lighting instructions.

171 844

Casing upper front control panel (less controls)

154 846

Casing assembly - complete .................................... CXSD 40/H

157 479

................................................................................... CXSD 50/H

157 480

................................................................................... CXSD 60/H

157 481

................................................................................... CXSD 70/H

157 482

................................................................................... CXSD 80/H

157 483

................................................................................... CXSD 90/100/H

157 484

................................................................................... CXSD 110/120/H

157 485

Key No.

Description

Qty.

Product No.

SHORT LIST OF PARTS

Ideal Boilers, P.O. Box 103, National Ave, Kingston upon Hull,
HU5 4JN. Telephone: 01482 492 251 Fax: 01482 448 858.
Registration No. London 322 137.

November 2005

UIN 157292 A03

Technical Training

Caradon Ideal Limited pursues a policy of continuing
improvement in the design and performance of its products. The
right is therefore reserved to vary specification without notice.

The Ideal Boilers Technical Training Centre offers a series of first class training courses for domestic, commercial and
industrial heating installers, engineers and system specifiers. For details of courses please ring: ........ 01482 498 432

Ideal Installer/Technical Helpline: 01482 498 376

www.idealboilers.com

157292-3.pmd

11/3/2005, 9:28 AM