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Concord CXDi/H -
Installation and Servicing
GENERAL
Boiler
CXDi 110/H
CXDi 120/H
CXDi 140/H
CXDi 160/H
CXDi 180/H
Boiler Input
Gross
kW
93.9
102.5
119.5
136.6
153.7
Low Rate
Btu/h x 1000
320.5
349.6
407.9
466.1
524.4
Nett
kW
84.6
92.3
107.7
123.1
138.5
Btu/h x 1000
288.7
315.0
367.4
419.9
472.4
Boiler Input
Gross
kW
134.2
146.4
170.8
195.2
219.6
High Rate
Btu/h x 1000
457.8
499.4
582.7
665.9
749.1
Nett
kW
120.9
131.9
153.8
175.8
197.8
Btu/h x 1000
412.4
449.9
524.9
599.9
674.9
Boiler Output
kW
110
120
140
160
180
High Rate
Btu/h x 1000
375.3
409.4
477.7
545.9
614.2
Gas rate
High
m
3
/h
12.78
13.95
16.27
18.59
20.92
ft
3
/h
451.5
492.5
574.6
656.7
738.8
Approx. flue
At 4.5% CO
2
& 100°C
m
3
/s
0.112
0.122
0.142
0.163
0.183
gas volume
At 4.5% CO
2
& 212°F
ft
3
/min
237
259
301
345
388
Burner
High
mbar
10.4
10.1
9.7
9.6
9.7
setting
in.w.g.
4.2
4.0
3.9
3.8
3.9
pressure
Low
mbar
5.1
4.9
4.8
4.7
4.8
in.w.g.
2.0
2.0
1.9
1.9
1.9
Part load efficiency (Gross)
%
83.0
81.6
82.5
82.9
82.8
Electricity supply
230 V ~ 50 Hz 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 1 minute 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
o
C.
Boiler thermostat
The boiler thermostat hysteresis is a maximum of 3
o
C.
Table 1 - Performance Data
Table 3 - Boiler Control specification
Maximum flow temperature 85
o
C
Boiler
CXDi 110/H
CXDi 120/H
CXDi 140/H
CXDi 160/H
CXDi 180/H
Number of sections
7
7
8
9
10
Flow connection
Rc
65mm (2
1
/
2
") nominal bore flange to BS4504 (PN6)
Return tappings
Rc
2 x 2
Maximum static head
m. (ft)
61.0 (200)
Maximum pressure
bar (psi)
6.0 (87)
Gas inlet connection
Rc
1
1/2
Minimum dynamic
mbar
17.5
17.5
17.5
17.5
17.5
gas pressure
in.
7
7
7
7
7
Electricity supply
230 Volts - single phase, 50 Hz, fuse 5 A
Nominal flue size (to BS. 835)
mm
250
250
250
250
300
in.
10
10
10
10
12
Diverter outlet socket
mm
288
288
288
288
344
internal diameter
in.
11.3
11.3
11.3
11.3
13.5
Length of burner bars (overall)
mm
535
535
535
535
535
in
21.1
21.1
21.1
21.1
21.1
Approximate dry weight
kg
520
520
587
654
721
lb.
1146
1146
1294
1442
1590
Water content
litre
53
53
60
68
76
gal.
11.7
11.7
13
15
17
Table 2 - General Data
Note. To obtain gas consumption in l/s divide gross heat input (kW) by a calorific value of 37.8(MJ/m
2
)
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Concord CXDi/H -
Installation and Servicing
CONTENTS
Air Supply. ........................................................................ 8
Boiler Assembly - exploded view. ................................. 9
Boiler Clearances. ........................................................... 5
Burner Assemblies - exploded views. .............................
CXDi 110/H-160/H. ..................................................... 28
CXDi 180/H. ............................................................... 29
Casing Assembly. .......................................................... 13
Chimney System. ............................................................. 8
Commissioning. ............................................................. 19
Electrical Connections. ................................................. 16
Electrical Supply. ............................................................. 8
Fault Finding. ................................................................. 32
Gas Safety Regulations ................................................... 2
Gas Supply. ....................................................................... 8
Hydraulic Resistance. ...................................................... 5
Initial Lighting. ............................................................... 19
Installation. ....................................................................... 9
Mandatory Requirements. ............................................... 7
Option Kits. ....................................................................... 4
Pump. ................................................................................ 6
Servicing. ........................................................................ 26
Short List of Parts. ......................................................... 35
Static Head Requirements. ............................................. 6
System Connections. ..................................................... 12
Ventilation. ........................................................................ 8
Water Circulation. ............................................................ 4
Water Connections. ......................................................... 4
Water Treatment. .............................................................. 6
Wiring Diagrams. ........................................................... 17
INTRODUCTION
CONSTRUCTION
BOILER BODY
The sectional boiler body is of cast iron and is supplied with a sheet
steel combustion chamber and integral draught diverter. The boiler
is supplied in sectioned form for site assembly.
CASING
The casing is manufactured in stove enamelled sheet steel and is
easily assembled on site.
BURNERS
The 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 CXDi 110/H-180/H range of boilers has been tested
and certified by British Gas to prEN656 for use with natural gas only.
Note.
Concord CXDi 110/H - 180/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.
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 Concord CXDi/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.
Concord CXDi 110/H-180/H (Natural gas) B.G. Certified - P.I. No. 87/AQ/341 Destination Countries: GB and IE
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.
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Concord CXDi/H -
Installation and Servicing
GENERAL
Boiler Size
Cold Feed
Open Vent
CXDi 110/H
1"
1
1/4
"
CXDi 120/H
1"
1
1/4
"
CXDi 140/H
1"
1
1/4
"
CXDi 160/H
1
1/4
"
1
1/2
"
CXDi 180/H
1
1/4
"
1
1/2
"
1
WATER CONNECTIONS
Flow connection is 65mm (2
1
/
2
") nominal bore flange to BS4504 (PN6).
Return tappings are 2" BSP.
The distributor tube must be fitted into the return connection. The flow header must be
fitted in the flow pipe.
The open vent must be brought to either the 1
1/2
" BSP tapping on the flow header or to
the unused 2" BSP tapping at the top rear of the boiler.
The cold feed may be brought to the LH front bottom tapping in
order to avoid excessive surging or pumping over. The unused
bottom rear tapping must not be used for the cold feed pipe as it is
practically blocked by the distributor tube.
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.
2
) above the operating pressure in the boiler. The
maximum safety valve setting is 0.7 bar (10 lb/in.
2
) above the
maximum design operating pressure of 6.0 bar (87 lb/in.
2
).
Cold Feed/Open Vent
The independent cold feed and the open vent must comply with
BS. 6644 and be of the following minimum size.
OPTION KITS
Remote indication board (volt free)
This provides the ability for remote indication of lockout and
overheat conditions.
Outside sensor
This kit provides 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. 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
- in order to make use of this the pump must be wired to the
appropriate terminal L
2
(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 CXDi 110/H and CXDi 120/H the minimum circuit
during pump overrun could be a load of 7 kW with a volume
of 42 litres or any other combination given by the relevant
line.
b. For the CXDi 180/H the minimum circuit during pump overrun
could be a load of 9 kW with a volume of 70 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.
The wiring diagrams in Frames 16,17 and 18 illustrate the control
methods for achieving the above.
3. Pump selection should take account of the hydraulic resistance
given in Graph 2.
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Concord CXDi/H -
Installation and Servicing
GENERAL
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.
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
0
C
(150
0
F).
Graph 2 - Hydraulic Resistance
Boiler Size
CXDi 110/H
CXDi 120/H
CXDi 140/H
CXDi 160/H
CXDi 180/H
Front clearance
mm (in)
700 (27
1/2
)
Rear clearance
mm (in)
200 (8)
Side clearance
mm (in)
100 (4) - not including clearance for side fitted flow header
Dimension A
mm (in) 1036 (40
3/4
) 1036 (40
3/4
)
1036 (40
3/4
)
1086 (42
3/4
)
1140 (45)
Dimension B
mm (in)
175 (7)
175 (7)
175 (7)
197 (7
3/4
)
250 (10)
Dimension C
mm (in) 1107 (43
3/4
)
1107 (43
3/4
)
1230 (48
1/2
)
1353 (53
1/4
)
1476 (58
1/8
)
Dimension D
mm (in)
816 (32
1/8
)
816 (32
1/8
)
939 (37)
1062 (42
3/4
)
1185 (46
5/8
)
Dimension E
mm (in)
553 (21
3/4
)
553 (21
3/4
)
615 (24
1/4
)
676 (26
5/8
)
738 (29)
Dimension F
mm (in)
220 (8
5/8
)
220 (8
5/8
)
220 (8
5/8
)
220 (8
5/8
)
320 (12
1/2
)
2
CLEARANCES & DIMENSIONS
Table 4
Graph 1 - Heat Load / Water Volume
CXDi
160/H
Con
1935
CXDi
110/H
CXDi
120/H
CXDi
140/H
CXDi
180/H
CXDi
180
/H
CXDi
160/H
CXDi
1
1
0
/H
CXDi
120
/H
CXDi
140
/H
Con
1936
1
Con
1934
+:,E
C O N C O R D
EXIT COPY ENTER
YES
NO
ADV
I
II
Return Rc2
(2" BSP)
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Concord CXDi/H -
Installation and Servicing
GENERAL
Note. This diagram does not show safety valves, water flow switches, etc.,
necessary for the safe operation of the system.
3 OPEN VENTED SYSTEMS - minimum static head requirements
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 and BS.6700.
The information provided is based on the
following assumptions:
1. The open vent MUST be brought to either
the 1
1/2
" BSP tapping on the flow header
provided or to the unused 2" BSP flow
tapping at the top rear of the boiler.
2. An independent cold feed/expansion pipe
connection is made to the LH lower front
connection. 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.
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.
Conversely, when the system cools, water previously expanded 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,
Table 5 - Flow rates for fully pumped systems
Boiler
Minimum flow rates for a
temperature difference of 35°C (63°F)
l/s
g.p.m.
CXDi 110/H
0.75
9.9
CXDi 120/H
0.82
10.8
CXDi 140/H
0.96
12.7
CXDi 160/H
1.10
14.6
CXDi 180/H
1.24
16.4
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.
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Concord CXDi/H -
Installation and Servicing
GENERAL
Limitations of Intended Operating Environment
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.
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.
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 the 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 the 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
Working pressure 6.0 bar maximum.
Particular reference should be made to BS. 6644: Section 6
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.
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.
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, Marlowe Way
Betz Dearborn Ltd.,
Croydon.
Widnes,
Surrey CRO 4XS
Cheshire, WA8 8UD
Tel 0870 601 5000
Tel. 0151 424 5351.
SAFE HANDLING OF SUBSTANCES
Care should be taken when handling the boiler insulation panels,
which can cause irritation to the skin. No asbestos, mercury or
CFCs are included in any part of the boiler.
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.
4
SEALED (PRESSURISED) SYSTEMS
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Concord CXDi/H -
Installation and Servicing
GENERAL
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 vermiculite 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 CXDi/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 in accordance with BS. 6891;
IGE-UP-1 for small installations
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.
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.
VENTILATION
Safe, efficient and trouble-free operation of conventionally 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 directly with the outside air is required at
both high and low levels. The minimum free areas of these grilles
must be according to the following scale:
Table 6 - Ventilation Requirements
Required area (cm
2
) per kW of total rated input (net)
Boiler room
Enclosure
Low level (inlet)
4
10
High level (outlet)
2
5
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).
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.
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.
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INSTALLATION
5
CONCORD CXDi/H BOILER ASSEMBLY - Exploded view
Insulation not shown
Legend
1. Cleanout cover.
2. Collector hood.
3. Middle section.
4. Flow header.
5. Section alignment rings & 'O' rings.
6. Thermostat pocket.
13. Combustion chamber.
14. Tie rods.
15. Lightback shield.
16. Burner manifold assy.
17. NOx duct.
18. Insulation Bracket.
7. End section.
8. Distribution tube.
9. Downdraught deflector.
10. Section bolt.
11. Drain cock.
12. Base plate.
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
6
BOILER SECTION ASSEMBLY
The site assembled boiler is supplied in the following packages:
! Combustion chamber / manifold / burner assembly.
! Platework package.
! Casing package.
! Controls box package.
! End and centre sections.
TOOLS REQUIRED
!
Spanners
!
Torque wrench
!
Pozi screwdriver
!
Mallet
GENERAL
The installation of the boiler must be in accordance with current
Gas Safety (Installation and Use) Regulations 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.
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
final siting.
Prior to assembling the sections it will be necessary to remove
the manifold assembly and burners from the combustion chamber.
To do this:
1. Undo the 2 M5 screws and washers securing the spark
generator bracket to the combustion chamber. Undo the
union securing the gas valve assembly and remove the gas
valve and spark generator assembly from the boiler.
2. Undo the 4 nuts securing the burner manifold to the
combustion chamber legs.
3. Undo the nuts securing the burner light back shield to the
combustion chamber and lift it off.
4. Pull the whole burner assembly forward on its runners,
ensuring that no wires are trapped, and remove it
completely from the combustion chamber.
PREPARATION OF SECTIONS
Each section should be brushed clean on all external
surfaces and any debris which may have accumulated
within the sections should be removed via the bottom ports.
Section Assembly - refer to the exploded view
5. Take an end section and lift it onto the combustion
chamber so that the combustion chamber side panel
return is inside the section rear lip.
6. 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 end 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 recessing 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 sections coming apart.
8. Repeat the assembly procedure for all of the sections until
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. For open vented systems a site test must be carried out at
a hydraulic pressure equal to 1
1/2
times the design
pressure given in Table 2, for a period of 30 minutes.
Note. If it is a sealed system the hydraulic pressure must
be equal to twice the given design pressure for 30
minutes.
11. Fit the 4 coach bolts into the lugs at the bottom of the end
sections and through the hole in the retaining angle of the
combustion chamber.
Fit a flat washer and nut and secure the section assembly
to the combustion chamber.
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11
Concord CXDi/H -
Installation and Servicing
INSTALLATION
7
BOILER SECTION ASSEMBLY - continued
12. Offer the downdraught deflector to the projecting studs at
the back of the combustion chamber and fix, using the
nuts and washers provided to the downdraught deflector.
13. Fit insulation brackets with the screws provided.
14. Refit the burner assembly to the combustion chamber
and tighten the 4 nuts securing the burner manifold to the
combustion chamber legs. Offer up the burner light back
shield to the combustion chamber - with the cutout for the
flame detector electrode at the LH end - and fasten, using
the M5 nuts and washers.
15. Fit the gas valve and spark generator assembly to the
boiler by doing up the union in the gas line and by
fastening the spark generator bracket to the
combustion chamber using the two M5 screws and
washers.
16. Fit the gas inlet pipe and retain by the semi-circular
clamp, screws and washers provided. Tighten both
unions and the inlet pipe retaining clamp, ensuring that
the gas valve assembly is vertical.
17. To fit the collector hood align the back edge of the
horizontal side returns with the rear of the section
assembly and fasten down the collector hood (using
the M6 screws and nuts provided) through the side
fixing points.
18. Wrap insulation around heat exchanger with foil
outside, tuck behind insulation brackets on
downdraught deflector. Fasten at edge using foil tabs
and tape provided.
19. Fit the NOx ducts into the burner aeration intakes and
fasten to the collector hood, using the M5 elongated
nuts. Insualtion must be behind NOx ducts, note that
the insulation will be compressed flat behind ducts.
Side elev. of d/deflector-insulation assy.
Con
1902
Sealing rope
Downdraught
deflector
Fixing screw
Collector hood flange
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
8
BOILER ASSEMBLY
1. Fit the distributor tube into the selected return connection.
Ensure that the tube flange aligns horizontally and that the
2 sealing gaskets are correctly assembled on the tube -
refer to alignment notches.
1. Complete the secondary flue connection.
The boiler is designed to accept flues to BS.835. If a
suitable adaptor is used then flues to BS715 may be fitted.
2. Seal with an approved boiler putty.
3. A split socket should be fitted immediately above the boiler
to facilitate disconnection of the flue.
9
FLUE CONNECTION
Connect the gas supply to the gas inlet pipe - Table 2
gives details of the inlet pipe size.
The use of an approved gas cock and union is
recommended here.
Fit the 2" tapped flange, using the M10 x 35mm screws and
washers provided.
2. Fit the blank flange to the other lower rear connection, using
the gasket and M10 x 25mm screws and washers provided.
3. Fit the blank flange to the RH front connection, using the
gasket and M10 x 25mm screws provided.
4. The 1
1/
4" tapped flange and gasket should be fitted to the
LH front connection with the reducing bush and
1/2
" drain
cock. If the cold feed/expansion pipe is to be brought directly
to the boiler, the close taper nipple and 1
1/4
" tee must be
fitted so that the drain cock is horizontal. This will reduce
the possibility of the drain becoming blocked by debris.
5. Complete the system connections (using suitable jointing
compound) as follows:
The cast iron flow header must be fitted in the chosen flow
connection which will be either of the 2 top rear tappings.
A length of 2" BSP pipe is contained in the Plateware
Package for this purpose.
Fit the flow header so that the 1
1/2
" vent tapping in the
header is vertical. Screw the thermostat pocket into one of
the
1/2
" tappings.
The other
1/2
" tapping is used for the pressure gauge
provided. The flow header terminates in a 2
1/2
" flange
connection.
The 1
1/2
" BSP tapping on the top of the flow header is for
a vent pipe ONLY and MUST NOT be used for any other
purpose.
A safety valve may be fitted in the remaining top rear
tapping, in accordance with CP332:3.
The unused top rear tapping may be used as an
alternative and independent open vent / safety pipe
connection. The LH front bottom tappings may be used for
an independent cold feed / expansion pipe connection.
In order to avoid air locks, reduction in pipe sizes should
be made in the vertical plane or eccentric bushes used.
Finally , plug the unused tappings, using the 2" BSP plugs
supplied.
10 GAS CONNECTION
Con 1467
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
11 CASING ASSEMBLY
1. Fit the support angle to
the collector hood and
fasten, using the M5
screws and washers.
2. Fit the front fixing
bracket(s) to the collector
hood and fasten, using the
M5 screws and washers
through the slotted holes.
3. Fit one side panel over its
brackets on the
combustion chamber base
tray and fasten to the
support angle, using the
M5 screw and washer.
Repeat for the other side
panel.
4. Fit the upper front support
framework with the
overheat thermostat at the
bottom and with its green
Legend
1. Side panel.
2. Supporting angle.
3. Top panel.
4. Upper front panel.
5. Control box.
6. Bracket.
7. Support frame.
8. Door panel.
9. Lower panel.
button facing to the RH side and secure to the
front fixing bracket(s), using the M5 screws and
washers, and to each side panel, using the No.8
screws.
5. Fit the 4 shoulder screws into the fixings at the
bottom of the front return of the casing side
panels.
6. Finally, ensure correct alignment by slackening
and retightening the screws into the slotted holes
in the front fixing bracket(s).
Con 1466
6
5
7
8
9
4
3
1
2
Con 1906
Overheat 'stat reset button
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
12 CONTROL BOX
1. Make the 3 electrical connections from the overheat
thermostat (fixed to the upper front framework) to the
terminals marked 'Limit Stat' on the electrical plug-in
connector from the gas valve plug lead assembly, as
follows:
C Pink
N/O Red
N/C White
Ensure that the lead is securely fastened under the strain
relief clamp - but bring the earth wire outside the clamp
before tightening
2. Unpack the control box. Fit the plug-in connector from
the gas valve plug lead assembly to the bottom box at the
back of the control box and fasten, using the M4 screws
and washer.
3. Fit the control box to the support frame and
fix at the bottom using the 2 self tapping
screws provided.
4. Fit the earth connections from the terminal
plug-in connections to the appropriate earth
posts on the back of the control box.
Connect the earth lead prefitted to the
control box back panel to the threaded hole
in the casing support frame.
IMPORTANT
5. Offer up the spark generator assembly to
the combustion chamber base tray and
secure the bracket, using the M5 screws
and washers.
Plug the spark generator leads onto the
spark electrode connections on the RH end
burner - access via the side of the
combustion chamber.
6. Ensure the electrical cover is correctly
fastened to the spark generator
Con 1309
C N/O
N/C
3
Con 1468
5
Spark
generator
leads
Con 1912
2 push-in
connections
Con 1913
Electrical cover
Flame detector lead
6
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
13 CONTROL BOX - continued
7. Run the flame detector lead through the clips on the front of
the combustion chamber base tray and plug it into the flame
detector electrode on the LH end burner. Ensure that any
slack is tucked neatly into the clips then fasten the clips.
8. Unstrap the thermostat sensor lead and run both the sensor
and the overheat thermostat phial through the clips on the
appropriate casing side panel to the flow header, ensuring
that both leads run under the support angle.
9. Secure both phials into the thermostat pocket in the flow
header, using the spring clip.
10. Fit the earth connections from the
terminal plug-in connections to the
appropriate earth posts on the back
of the control box. Connect the
earth lead prefitted to the control
box back panel to the threaded
hole in the casing support frame.
11. Fit the casing upper front panel
with its location buttons in the slots
and push down to locate. Fasten at
the bottom, using the No.8 screws.
12. Fit the casing lower front panel by
locating its slots over the shoulder
screws in the side panels and
pushing down to locate.
LH Burner
Flame
detector
NOx duct
7
Con 1915
8
Con 1914
Spring clip
Overheat thermostat capillary
Control thermostat lead
Thermostat pocket
9
Con 1916
Earth connections
GV1 & GV2 & o/heat
thermostat earths
Con 1917
10
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
14 ELECTRICAL CONNECTIONS
WARNING. This boiler must be efficiently earthed.
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.
All wiring that is associated with the EXT C terminals should
be separated from other current carrying cables by a
minimum of 100mm. It is preferable to have the volt free
contacts as close to the boiler control as possible thereby
avoiding long lengths of cable to the EXT C terminals on the
boiler control panel.
The boiler provides frost protection via the boiler sensor. If
an external frost thermostat is required contact Caradon
Ideal Limited.
The internal wiring of the boiler control box is shown in Frame
15.
Wiring should be PVC insulated cable, not less than 0.75mm
2
(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 conductors
become taut before the earthing conductor, if the cable or
cord slips out of the cord anchorage.
The earth connections 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 nor should any permanent wiring prevent
the withdrawal of the burner tray for servicing.
Fit the plug-in connector into the mains voltage connection
box at the back of the control box and fasten, using the M4
screws and washers.
Check that the other 2 plug-in connectors are fitted into their
respective boxes.
Finally, fit the casing top panel and push down to locate.
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17
Concord CXDi/H -
Installation and Servicing
INSTALLATION
Boiler terminals
L2 N
PUMP
EXT C
L1 N
BOILER
Permanent Live Supply
Pump
Relay contact R4-1
Zone thermostats
R2-1
R1-1
Zone
valves
R3-1
close
open
R1-2
R2-2
R3-2
close
open
close
open
R1-3
R3-3
R2-3
R1
R2
R3
N
Relay No. 4
Con1470
Schematic
Wiring
16 ZONES WITH BI-DIRECTIONAL MOTORISED VALVES
15 INTERNAL WIRING
br brown
r
red
LEGEND
b blue
bk black
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 and Graph 1. 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 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.
Pump
Supply
Control panel
earth stud
Detail of
connection box
MAINS Voltage
Plug -in
connector
y
y pk v w or
b br
N L2
L1
EXT
FLOW
PUMP
UNSWITCHED
SUPPLY
CONTROLS SW
THESE CONTROLS
MUST BE VOLT
FREE CONTACTS
Installer connections
Control panel earth stud
GV2
GV1
N
Detail of
connection
box
MAINS
Voltage
Plug-in
connector
pk
y
b br or bk w
r
pk
pk
r
w
F1 F2
DET
N L5 L3
N
N
L4
GV2
GV1
IGN
br
b
y
y
v
or
w
pk
pk
Note:
Link
Note:
Link
y/g
Control
panel
earth stud
Front panel
earth lead
Filter
b
br
y/g
Control panel
earth stud
Ideal No. 34
or
or
y
w
y
w
br
y
b
r
w
bk
or
** Remote
indication
board
No.36
Ideal No. 35
LCD Board
Detail of
connection box
or or
LOW
Voltage
Plug-in connector
O/SEN CTRL
STAT
O/heat 'stat
pk
y
w
y
w
Con 1469
O/heat thermostat
y yellow
w white
v violet
pk pink
g/y green/yellow
or orange
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
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18
Concord CXDi/H -
Installation and Servicing
INSTALLATION
N
Relay No. 4
Boiler terminals
L2 N
PUMP
EXT C
L1 N
BOILER
Permanent Live Supply
Relay contact R4-1
Schematic
Wiring
Zone thermostats
Con 1471
R2 -1
R3-1
R2-2
R3-2
SP
(if req)
Zone 2
pump
Zone 1
pump
Zone 3
pump
R3
R2
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
Boiler terminals
L2 N
PUMP
EXT C
L1 N
BOILER
Permanent Live Supply
Pump
Relay 2 contact
Zone thermostats
N
Relay No. 2
Con1489
Schematic
Wiring
Zone 1
valve
Zone 2
valve
Zone 2
pump
S.P.
(if required)
Relay No. 1
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19
Concord CXDi/H -
Installation and Servicing
INSTALLATION
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 gastight 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.
20 INITIAL LIGHTING
21 LIGHTING INSTRUCTIONS
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).
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 1 minute 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 Concord CXDi/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 25-30.
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.
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.
19 COMMISSIONING AND TESTING
CXDi
C O N C O R D
EXIT
COPY ENTER
YES
NO
ADV
I
II
Con 1389
the ignition sequence should be reset by pressing 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.
Up/down
buttons
On/Standby
button
Display
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Concord CXDi/H -
Installation and Servicing
INSTALLATION
5
7
and
22 CHECKING THE MANIFOLD PRESSURES
6. Low rate adjustment screw.
7. Gas rate adjuster - maximum.
8. Burner setting pressure test
point.
9. Inlet pressure test point.
10. High/low solenoid connector.
Turn the boiler OFF by pressing the [0/1] button and allow the
flow temperature to cool to less than 50
0
C.
Connect a pressure gauge to the burner manifold test point
(Frames 23 or 24).
Press the [0/1] button again to turn the boiler ON.
The boiler will operate at low rate for approximately 3 minutes
before proceeding to high rate (this will only happen if the flow
temperature is below 55
0
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 & 24.
23 ADJUSTING THE MANIFOLD PRESSURES - CXDi 110/H - 160/H only
LEGEND
1. Fascia panel display.
2. Overheat thermostat.
3. Main gas inlet cock.
4. Union.
5. Gas control valve.
5a. High/low gas valve.
Con 1475
8
5
3
4
9
10,6
1
5a
2
4
+:,E
C O N C O R D
EXIT COPY ENTER
YES
NO
ADV
I
II
CON5229
$
Low rate adjustment screw
Gas rate adjuster
maximum
High solenoid plug
1. Press the [ENTER] button on the fascia panel, 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
Concord CXDi/H.
3. It is essential to adjust the maximum setting first.
SETTING THE HIGH BURNER PRESSURE
4. Adjust the system controls to ensure that the boiler will operate
at high rate for a reasonable period.
5. Remove the dust cover from the adjustment screw in the bottom
valve and gently screw the adjustment in fully.
6. Remove the plastic dust cover from the adjustment screw on
the top (high/low) valve and, using a spanner, screw the adjuster
gently fully in. Then screw the adjuster out until the burner
pressure to approximately 10.9 mbar.
7. Finally, screw out the adjustment on the bottom valve until the
burner pressure is correctly set to the value given in Table 1.
8. After setting, allow the boiler to operate for 3 minutes to
stabilise then recheck the setting.
SETTING THE LOW BURNER PRESSURE
9. Press the [0/1] button to turn the boiler off then disconnect
the 'high' solenoid plug from the top valve.
10. Disconnect the LH electrical plug from the bottom valve.
11. Turn the boiler on and set the low burner pressure to the
value given in Table 1, using the low rate adjustment screw
inside the spindle of the top valve.
12. Turn the appliance off and reconnect all the electrical plugs.
Do not overtighten the electrical plug fixing screws.
Refit both dust covers over the adjustment screws and refit
the pressure test point screw. Check for gas soundness.
13. Press [EXIT] to leave the commissioning mode and return to
the main menu.
14. Press [EXIT] again to return to the status displays.
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Concord CXDi/H -
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INSTALLATION
The Concord CXDi/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 provide a rapid spark at the ignition electrode for
up to 10 seconds.
The burner will light and remain at low rate for approximately
3 minutes before proceeding to high rate, when the
microprocessor opens the remaining gas valve(s).
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
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
0
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.
24 ADJUSTING THE MANIFOLD PRESSURES - CXDi 180/H only
1. Press the [ENTER] button on the fascia panel, 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 Concord CXDi/H.
3. It is essential to adjust the maximum setting first.
SETTING THE HIGH BURNER PRESSURE
4. Adjust the system controls to ensure that the boiler will
operate at high rate for a reasonable period.
5. Press the [0/1] button to turn the boiler off.
6. Undo the screws holding the electrical plug on the bottom
gas valve and pull it off.
7. Turn the boiler on and remove the plastic dust cover from
the adjustment screw on the top gas valve and using a
suitable spanner screw the adjuster gently fully in. Then
screw the adjuster out until the burner pressure is
approximately 9.0 mbar.
8. Turn the boiler off and refit the electrical plug on the bottom
valve.
9. Turn the boiler on and remove the dust cover from the
adjuster on the bottom valve. Set the burner pressure to
the value in Table 1.
Do not adjust the middle valve which is factory set.
10. After setting, allow the boiler to operate for 3 minutes to
stabilise then recheck the setting.
SETTING THE LOW BURNER PRESSURE
11. Press the [0/1] button to turn the boiler off then disconnect
the 'high' solenoid plug from the top valve.
12. Disconnect the electrical plug from the bottom and middle
valves.
25 OPERATING INSTRUCTIONS
7
Con 1983
Low rate adjustment screw
Gas rate
adjuster
maximum
Remove plastic
dust cover
High solenoid plug
9
Con 1984
Inlet Pressure
Test Point
Dust cover
13. Turn the boiler on and set the low burner pressure to the
value given in Table 1, using the low rate adjustment screw
inside the spindle of the top valve.
14. Turn the appliance off and reconnect all the electrical plugs.
Do not overtighten the electrical plug fixing screws. Refit
both dust covers over the adjustment screws and refit the
pressure test point screw. Check for gas soundness.
15. Press [EXIT] to leave the commissioning mode and return
to the main menu.
16. Press [EXIT] again to return to the status displays.
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INSTALLATION
26 ADDITIONAL FEATURES OF THE CONTROL SYSTEM
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 °C.
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 CXDi/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:
CXDi
C O N C O R D
EXIT
COPY ENTER
YES
NO
ADV
I
II
Con 1389
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
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 60°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 1 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.
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
27 DESCRIPTION AND OPERATION OF BOILER CONTROLS
Display
Up/down buttons
Onstandby button
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INSTALLATION
28 DESCRIPTION AND OPERATION OF BOILER CONTROLS - continued
The diagram below shows the sequence of steps to be taken when reading the instructions on the
following pages.
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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 required option 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:
or
or
or
- to select any of them use the [UP] or [DOWN] button until the
required option is displayed then 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 - 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 this option will have no effect.
If this advance has been selected, to cancel it then the same
procedure should be followed but the [NO] button pressed.
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INSTALLATION
30 DESCRIPTION AND OPERATION OF BOILER CONTROLS - continued
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 1.
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
o
C - 85
o
C.
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 and 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
o
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
o
C (in the example above, 85
o
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
o
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 degrees before the high
rate gas valve is energised.
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
o
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, displaying a message indicating the
nature of the fault to assist a speedy and effective repair.
See "Fault Finding" section for more details.
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SERVICING
32 TESTING
31 SPILLAGE CHECK
Check that there is no spillage of
combustion products from the boiler
draught diverter by carrying out a
spillage test, as detailed in BS. 5440:1.
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 40 and 41.
2. Check that the display shows "Detection lockout".
3. Turn on the gas cock and reset by pressing [COPY].
4. Fit the 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.
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.
If access is required to the electrical plug-in terminals at the
back of the control box then remove the casing top panel. It is
not advisable to try and remove the control box back panel
from the boiler with plugs in place.
CLEANING THE BOILER
Remove the casing door panel. Lift and remove the casing
lower front panel. Undo and pull off all the plugs from the gas
valve solenoids. Turn off the gas at the gas inlet cock. Undo
the 2 unions at either side of the gas valve assembly and
remove the assembly complete.
33 ADJUSTMENT OF WATER FLOW RATE THROUGH THE BOILER
When commissioning the heating/domestic hot water system the shunt pump must be adjusted to give the minimum flow rate
given in Table 4, when that part of the system intended to be used for dissipation of residual heat only is in operation.
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 their representative to
the Lighting and Operating Instruction Label on the inside of
the front panel. 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.
34 HANDING OVER
Hand these Installation and Servicing Instructions, User's Instructions
and Log book to the customer and request him to keep them 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
it to the owner or their representative.
Recommend that a contract for this work should be made with a CORGI
registered engineer.
SERVICING
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SERVICING
36 SERVICING - continued
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. In particular,
check that:
1. The ignition electrode shield and base fixing screws are
tight.
2. The electrodes are correctly positioned .
3. Check that the gap between the electrode tips is 4mm.
4. Reassemble in reverse order. Ensure that no wires are
trapped when replacing the burner tray. Refit the flue
baffles, cleanout cover, light back shield, NOx ducts,
electrode connections and casing panels.
When refitting the plugs to the gas valve solenoids do NOT
overtighten the fixing screws.
GENERAL
WARNING. ALWAYS turn OFF the gas supply at the gas inlet cock
and switch OFF and DISCONNECT the electricity supply BEFORE
working on the appliance.
37 REPLACEMENT OF COMPONENTS - Refer to Frames 5, 40 and 41.
Pull off the leads to the spark electrode on the RH end burner -
access via the side of the combustion chamber. Pull off the lead
to the flame detector electrode at the LH end burner.
Lift off the casing top panel. Undo the 3 elongated nuts from
each of the NOx ducts and remove all the ducts. Undo the M5
nuts and washers retaining the burner light back shield and
remove it. Undo the four M6 nuts and washers securing the
burner tray and carefully pull it from the boiler, ensuring that no
wires are trapped. Undo the screws securing the cleanout
cover(s) and remove. Lift out the flue baffles.
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 - take care not to
damage the insulation.
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.
LH burner
Insulation not shown
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SERVICING
39 MAIN BURNER
1. Remove the burner tray from the boiler, as described in
Frame 36.
2. Each burner can be removed by lifting it at the back and
pushing it backward to clear the injector. Disconnect the
spark electrode assembly and heat shield from the RH
burner (or the flame detector electrode from the LH
burner), as necessary.
3. Reassemble in reverse order.
1. Undo and pull off all the plugs from the gas valve
solenoids.
2. Turn off the gas at the gas inlet cock. Undo the 2 unions
at either side of the gas valve assembly and remove the
assembly (complete) to a suitable working area.
3. In order to be able to remove the faulty gas valve it will be
necessary to slacken or remove all the screws on either
the inlet or the outlet manifold and only those 4 screws
securing the faulty gas valve on the other manifold. The
faulty gas valve can then be removed and replaced.
Ensure that the arrow on the gas valve points in the
direction of flow.
4. Ensure that new `O' ring seals are fitted and that the 'O'
ring seals on the remaining gas valves are correctly in
place. Ensure that all screws are retightened.
5. Test for gas soundness.
6. Recommission the appliance and set the manifold
pressure, as described in Frames 22-24.
38 GAS CONTROL VALVE
40 BURNER AND CONTROLS ASSEMBLY - Exploded View - CXDi 110/H -160/H
9. Main burner LH
10. Main burner RH.
11. Ignition electrodes.
12. Detection electrode assembly.
PTP
Pressure test point.
LEGEND
1. Main gas inlet cock.
2. Gas inlet union.
3. 'O' ring seal.
4. High/Low Gas control valve
5. Gas control valve.
6. Spark generator.
7. Burner manifold.
8. Main injector.
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SERVICING
41 BURNER AND CONTROLS ASSEMBLY - Exploded view - CXDi 180/H
1. Pull out the spring clip in the thermostat pocket in the flow
header and pull out the overheat thermostat phial and
capillary.
2. Ensure that the electrical supply is switched OFF.
3. Lift off the casing front panel and top panel.
4. Unclip the capillary from its clips on the casing side panel.
5. Undo the 2 screws securing the overheat thermostat
assembly and withdraw the assembly.
6. Undo the screw and remove the cover.
7. Remove the wires.
8. Undo the backnut and remove the thermostat.
9. Fit new thermostat and secure with backnut.
10. Reconnect wires as follows:
1. Pink
1. White
3. Red
Reconnect the earth terminal.
LEGEND
1. Main gas inlet cock.
2. Gas inlet union.
3. 'O' ring seal.
4. High/Low Gas control valve
42 OVERHEAT THERMOSTAT
5. Gas control valve.
6. Spark generator.
7. Burner manifold.
8. Main injector.
9. Main burner (LH).
10. Main burner (RH).
11. Ignition electrodes.
12. Detection electrode assembly.
PTP
Pressure test point.
11. Reassemble in reverse order.
12. Ensure that the thermostat capillary is rerouted through the
casing side panel clips and that the phial is secure in the
pocket fitted to the flow header using the spring clip.
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SERVICING
43 CONTROL BOX - Basic Boiler Exploded View
45 PC BOARD NO. 34
1. Remove the casing door panel.
2. Undo and remove 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 pulling gently forward.
6. Release PCB No. 34 from the 7 plastic mounting
pins and 2 screws and pull it forward.
7. Reassemble in reverse order.
44 CONTROL SENSOR
1. Lift off the casing top
panel.
2. Trace the sensor lead to
the pocket in the flow
header, remove the
spring clip and remove
the sensor phial.
3. Unclip the sensor lead
from its clips on the
casing. Undo the screws
on the connector box plug
and remove it.
4. Fit the new sensor and reassemble in reverse order.
Con 1476
1
2
3
4
5
6
7
8
9
10
9. Printed circuit board No. RTC/34.
10. EMC filter.
11. Controls box fascia (not shown).
LEGEND
1. Wiring clamp.
2. Connection box plug.
3. Connection box.
4. Printed circuit board No. 34.
5. Back panel.
6. Controls box.
7. Printed circuit board No. 35.
8. Ribbon cable.
SER
VICING
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Installation and Servicing
SERVICING
46 PC BOARD NO. 35
47 PC BOARD NO. RTC/34
1. Remove the casing door panel.
2. Undo and remove 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. Reassemble in reverse order.
1. Remove the casing door panel.
2. Undo and remove 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 pulling gently forward.
4. Reassemble in reverse order.
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.
SER
VICING
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Installation and Servicing
FAULT FINDING
49 BOILER CONTROL
user, the boiler will go to low rate and when the temperature
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 valves will operate.
On start up, the high rate gas valves will operate immediately
after detection if the boiler flow rate is greater than 55 °C.
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
o
C-85
o
C, in 1
o
C
steps, with an accuracy of ± 2
o
C and hysteresis of 3
o
C.
The full sequence control enables 5 attempts at ignition, with 1
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 "Lock-out" the pump will continue to run only if the
temperature is greater than 75
o
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.
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
trouble-free operation. The Anti-cycle duration is 1 to 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
o
C when the heat
demand is satisfied and will continue to run until the boiler flow
is less than 75
o
C. If the flow temperature is less than 75
o
C
when the demand for heat is satisfied the pump will cease to
operate.
Frost protection is inbuilt with the boiler. If the flow temperature
falls to approximately 3
o
C then the boiler will operate until the
flow temperature exceeds 4
o
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.
1 set of volt-free contacts is for "Lockout" and "Overheat"
combined and 1 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 a 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 to 3 minutes, the high rate gas
valves will open. On reaching the set point, determined by the
FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING
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Concord CXDi/H -
Installation and Servicing
FAULT FINDING
F
AUL
T FINDING
50 SIMPLE FLOW CHART OF OPERATION
SHUTDOWN
DELAY
IGNITION
LOW RATE
HIGH RATE
Prepurge completed
Flame = ON
PUMP OVERRUN
IF > 75°C OFF < 75°C
Temp >set
point
Flame = ON
For > 55°C no delay
If < 55°C
3 minutes
Demand
= off
Overrun
completed
Demand = ON
If > than
set point
FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING
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Concord CXDi/H -
Installation and Servicing
FAULT FINDING
51 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]
Press [O/1] button
Check wiring.
Press [Copy]
Check water
flow.
Press [Copy]
Replace o/h stat.
Press [Copy]
Check system.
Press [Copy]
Refer to
screens
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 ?
NO
Refer to
screens
Check gas
pressure.
Press [Copy]
Check
wiring.
Press [Copy]
Replace faulty
solenoid.
Press [Copy]
Refer to
screens
Change
gas valve
or
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
NO
NO
NO
YES
YES
Check boiler
programme timer and
status, as described
in Frame 29.
Does programme
timer require heat ?
FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING
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Concord CXDi/H -
Installation and Servicing
SHORT LIST OF PARTS
When ordering spare parts please quote:
1. Boiler model
2. Boiler serial no. (refer to the data plate on the combustion chamber)
3. Boiler 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.
Key No.
Description
Qty.
Product No.
Gas valve
28
HONEYWELL VR4605PB2003 CXDi 110/H, 120/H, 140/H, 160/H & 180/H
1
111 867
28.1
HONEYWELL VR4605A 1104 ...................................... CXDi 110/H & 120/H
1
138 896
HONEYWELL VR4605A 1104 ...................................... CXDi 180/H
2
138 896
28.2
HONEYWELL VR4605AB 1019 .................................... CXDi 140/H & 160/H
1
111 869
28.3
Plug and lead .................................... CXDi 110/H, 120/H, 140/H, 160/H & 180/H
1
154 734
28.4
Plug and lead .................................... CXDi 110/H, 120/H, 140/H & 160/H
1
139 269
28.5
Plug and lead .................................... CXDi 110/H, 120/H, 140/H & 160/H
1
112 431
28.6
Plug and lead .................................... CXDi 110/H, 120/H, 140/H, 160/H & 180/H
1
155 657
28.7
Plug and lead .................................... CXDi 180/H
2
111 870
29
Spark generator
1
139 300
31
Injector 4.02 mm diameter ......................................................... CXDi 110/H
6
013 175
Injector 4.20 mm diameter ......................................................... CXDi 120/H
6
013 180
Injector 4.20mm diameter .......................................................... CXDi 140/H
7
013 180
Injector 4.20mm diameter .......................................................... CXDi 160/H
8
013 180
Injector 4.20mm diameter .......................................................... CXDi 180/H
9
013 180
32
Flame detection electrode
1
138 895
32.1
Flame detection lead
1
139 271
33
Main burners ............................................. Worgas
CXDi 110/H & 120/H
5
139 824
Main burners ............................................. Worgas
CXDi 140/H
6
139 824
Main burners ............................................. Worgas
CXDi 160/H
7
139 824
Main burners ............................................. Worgas
CXDi 180/H
8
139 824
34
Main burner (RH end) ............................... Worgas
CXDi 110/H - 180/H
1
139 825
36
Ignition electrode
1
112 365
45
Control box complete
1
155 642
46
Thermistor
1
112 289
47
PCB No. 34
1
069 957
48
PCB No. 35
1
069 960
49
Real time clock
1
069 958
50
PCB 34 and real time clock
1
069 959
51
Ribbon cable
1
069 961
When replacing a part on this appliance use only spare parts that you can be assured conform to the safety and performance
specification that we require. Do not use reconditioned or copy parts that have not been clearly authorised by Ideal Boilers.
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SHORT LIST OF PARTS
Key No.
Description
Qty.
Product No.
56
Casing assembly complete
............................... CXDi 110/H & 120/H
1
157 449
56
Casing assembly complete
............................... CXDi 140/H
1
157 450
56
Casing assembly complete
............................... CXDi 160/H
1
157 451
56
Casing assembly complete
............................... CXDi 180/H
1
157 452
57
Casing front panel
............................... CXDi 110/H & 120/H
1
155 647
57
Casing front panel
............................... CXDi 140/H
1
155 648
57
Casing front panel
............................... CXDi 160/H
1
155 649
57
Casing front panel
............................... CXDi 180/H
1
155 650
58
Casing LH side panel
CXDi 110/H-180/H
1
076 978
59
Casing RH side panel
CXDi 110/H-180/H
1
076 979
60
Casing lower front panel
............................... CXDi 110/H & 120/H
1
138 475
60
Casing lower front panel
............................... CXDi 140/H
1
138 474
60
Casing lower front panel
............................... CXDi 160/H
1
138 473
60
Casing lower front panel
............................... CXDi 180/H
1
138 472
61
Casing upper front panel
............................... CXDi 110/H & 120/H
1
155 643
61
Casing upper front panel
............................... CXDi 140/H
1
155 644
61
Casing upper front panel
............................... CXDi 160/H
1
155 645
61
Casing upper front panel
............................... CXDi 180/H
1
155 646
62
Casing top panel
............................... CXDi 110/H & 120/H
1
138 465
62
Casing top panel
............................... CXDi 140/H
1
138 464
62
Casing top panel
............................... CXDi 160/H
1
138 463
62
Casing top panel
............................... CXDi 180/H
1
138 462
63.2
Overheat thermostat
1
155 269
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 157295 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
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