110531-9.pmd

Super Plus -

Installation and Servicing

CONTENTS

Assembly of Boiler ......................................................... 15

Boiler Description ............................................................. 5

Boiler Dimensions ............................................................ 9

Boiler House Clearances ................................................. 8

Boiler Operational Requirements .................................... 3

Boiler Specifications ........................................................ 4

Combustion Data Sheet ................................................. 26

Commissioning and Testing .......................................... 16

Control Sequence Logic ................................................. 23

Electrical Supply ............................................................. 13

Exploded Views

Boiler Assembly ........................................................... 5
Electrical Controls ....................................................... 6
Gas Line ........................................................................ 7
Module .......................................................................... 6

Fault Finding .................................................................... 24

Flue Requirements ......................................................... 10

General Information .................................................. 3 - 13

Installation ............................................................... 14 - 18

Installation Requirements ................................................ 7

Location ............................................................................ 8

Replacement of Components ........................................ 20

Safety Checks ................................................................ 17

Servicing Instructions .................................................... 19

Servicing and Fault Finding ..................................... 19 - 24

Short List of Parts .......................................................... 25

Water Circulation System .............................................. 12

Wiring Diagrams ............................................................. 14

INTRODUCTION

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.

BOILER OPERATIONAL REQUIREMENTS

The SUPER PLUS range of boilers is suitable for fully pumped
open vented or pressurised central heating, indirect domestic
hot water and combined systems.
WARNING: In order to ensure safe, efficient and reliable
operation of the boiler, particular attention should be made to
the following points:
1. The Super Plus incorporates an aluminium alloy heat

exchanger. As part of the installation the central heating system
should be thoroughly flushed with appropriate water treatment
in order to comply with BS7593:1992.
Under no circumstances should the boiler be fired before the
system has been thoroughly flushed.
Caradon Ideal Limited recommend only the use of Femox or
Betz Dearborn water treatment products, which must be used
in accordance with the manufacturers instructions. For further
information contact:
Fernox, Fry Technology UK, Tandem House, Marlowe Way,
Beddington Farm Road, Croydon. CRO 4XS, tel. 0870 5601
5000 - or - Betz Dearborn Ltd., Sentinel Division, Foundry
Lane, Widnes, Cheshire WA8 8UD, Tel. (0151) 424 5351
IMPORTANT : ANY OTHER TREATMENT FOR THIS PRODUCT
WILL RENDER THE GUARANTEE OF CARADON IDEAL LIMITED
INVALID.
Notes.
If an inhibitor is used, and in hard water areas where treatment
to prevent lime deposits is necessary, it is most important that
the water treatment MUST be maintained at the correct
concentrations recommended by the treatment manufacturer.
Persons responsible for the continued operation of this boiler
should be made aware of this requirement.
If the boiler is installed in an existing system then any
unsuitable water additives MUST be thoroughly drained.
Artificially softened water must not be used in the system,
under any circumstances.
In old systems the fitting of a filter to the return pipework, in
order to prevent debris reaching the heat exchanger, is
essential.

2. The constant water flow rate through the boiler, within ±10%

of that indicated in the data table, must be maintained at all
times when any of the modules are operating. At these flow
rates the hydraulic resistance is 98 mbar (39 in.w.g.) ±20%,
irrespective of the size of the boiler.

3. Protection against circulating pump failure must be provided.
4. The chimney system must be double skinned, or single wall

lined and insulated with the equivalent of 50 mm (2") of mineral
wool, aluminium covered. A drainage point must be provided.

Super Plus 200/S, 300/3, 400/4, 300/3 Alternative, 400/4 Alternative, 500/5 & 600/6

B.G. Certified - P.I. No. 87AP18

Destination Countries: GB & IE

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Super Plus -

Installation and Servicing

Boiler Model No.

200/S

300/3

400/4

300/3

400/4

500/5

600/6

Alternative Alternative

No. of Modules

Heat Output

200

300

400

300

400

500

600

Btu/h x 10

682.4

1023.6

1364.8

1023.6

1364.8

1706.0

2047.2

Heat Input

235

353

471

353

471

588

706

Btu/h x 10

802.9

1204.4

1607.0

1204.4

1607.0

2006.2

2408.8

Gas Rate

22.1

33.1

44.2

33.1

44.2

55.1

66.2

(Note 1)

778.8

1168.0

1558.7

1168.0

1558.7

1945.8

2336.4

Flue Gas Volume

l/s

109

164

218

164

218

273

327

at 100

C, 8.5% CO

/min

231

397

463

347

463

578

694

Required Water Flow Rate

l/s

4.3

6.5

8.6

6.5

8.6

10.8

12.9

(+/-10%)

gal/min

56.8

85.2

113.6

85.2

113.6

142.0

170.4

Hydraulic Resistance

mb (in.w.g)

98 (39)

Min. Static Head (Note 2)

m (ft)

1.6 (5)

Max. Static Head

m (ft)

60 (197)

Electricity Supply

Nominal 230 V, 50 Hz, Single Phase. Max start current 1.9 A per module

Max. Running Power

400

600

800

600

800

1000

1200

Min. Gas Supply

14.6

14.8

15.1

14.8

15.1

15.5

16.0

Pressure ( Note 3)

in. w.g

5.8

6.1

5.9

6.1

6.2

6.4

Boiler Height - overall

m m

1800

1900

74.8

Boiler Width - overall

m m

910

1510

2115

35.8

59.5

83.25

Boiler Depth - overall

mm (in)

990 (39)

Weight of casing

134

144

208

296

318

459

Weight of Each Module

69.2

152.5

Weight of Water Header

16.3

38.2

49.8

84.2

109.8

Weight of Gas Header

3.5

9.4

12.6

7.7

20.7

27.7

Water Content

19.8

29.7

39.6

29.7

39.6

49.5

59.4

(excluding header)

gal

4.4

6.5

8.7

6.5

8.7

10.9

13.1

Weight of Dry Boiler

308.5

437.4

506.6

437.4

506.6

666.2

735.4

681.2

964.3

1116.9

1964.3

1116.9

1468.7

1621.3

Weight of Wet Boiler

328.3

466.9

546.1

466.9

546.1

715.6

794.6

724.9

1029.3

1203.9

1029.3

1203.9

1577.7

1752.3

Flow and Return

m m

125

Connection (Note 4)

2.5

Gas Connection

Rc (in. BSP)

40 (1.5)

2 (2)

Flue Pipe Size

m m

250

350

450

(nominal bore)

Flue Socket Size

m m

288

401

500

(Note 5)

11.3

15.8

19.7

Burner Injector Size

m m

12.0

0.47

Main Burner Pressure

mbar (in.w.g)

2.7 (1.1)

Fan Motor

Type BCP 1506E : 230 V, 50 Hz, Single Phase, 75W, `06' rating

Gas Type

GENERAL

Notes:
1. Flue gas volumes and gas rates are calculated using a C.V. of

1031 Btu/ft

(at 15

C & 1013.25 mb)

2. For further information on head requirements see page 6.
3. The minimum gas supply pressure is with all modules firing.
4. Flange size: refer to BS.4504 Pt.1

GENERAL

5. Flues to BS.835 will fit directly onto the 300/3 Alternative,

400/4 Alternative, 500/5 and 600/6 boilers. For all boilers
single skin and metal flues may need a suitable adapter.
Further advice may be obtained from Caradon Ideal
Limited.

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Super Plus -

Installation and Servicing

GENERAL

LEGEND

1. Flue test point
2. Water header
3. Gas pressure test

point

4. Module
5. Module upper cover
6. Module lower cover
7. Gas header

Fig.1 Boiler Assembly - Exploded View

GENERAL

5. The chimney draught must be controlled between neutral

and 0.2mbar (0.08 in.w.g.).

6. Boilerhouse cleanliness is important and concrete floors

should be sealed to keep dust to a minimum. Contamination
of the air supply with chlorides should be avoided.

Regular maintenance by competent personnel is essential to
the safe and reliable operation of the boiler. Full details of these
requirements are given in these Installation & Servicing
Instructions.

BOILER DESCRIPTION

Each boiler consists of the following packs:
(a) The insulated stainless steel casing with flue outlet,

condensate drain, wiring centres and wiring harnesses and
for 300/3 or 500/5 boilers only, blanking kit.

(b) Boiler modules.
(c) Gas header, flow and return water headers and module

fixing packs.

(d) Extra blanking kit and support bracket kits for the 300/3

Alternative and 400/4 Alternative boilers only.

Note: The 300/3 Alternative and 400/4 Alternative are sold with
a view to later upgrading.

MODULE DESCRIPTION

The module can be subdivided into 3 main elements:
(a) The heat exchanger consisting of finned aluminium tubes

expanded into cast aluminium tube plates. The bottom cover
plate is cast aluminium. The top cover plate is cast iron,
fitted with cast iron flow and return elbows.

(b) The gas line which supplies and regulates the gas flow to

the main burners.

(c) The controls assembly which incorporates the fan (supplying

air for combustion) and the electrical controls.

The normal mode of operation of the boiler (described below) is
preceded in certain conditions by a phase in which the complete
boiler casing is given a 5-volume air change. This air change is
an important safety feature of BS.5978 and will occur whenever
the boiler goes from a situation of no modules firing to a situation
of one module firing. This includes morning start-up and those
occasions of low load when the last module firing goes off on its
thermostat (or external controls) and is then called again. The
air change will NOT occur if one or more modules are firing and
a further module is called.
The 5-volume air change phase operates as follows:
All the module fans are energised and run for approximately 70
seconds. At the end of this period all the fans are switched off
except for that on the module being called which then immediately
enters its 35 second, pre-purge period, (see Fig. 20).
When the electronic control thermostat calls for heat, the fan is
switched on and purges the combustion chamber for
approximately 35 seconds. At the end of this period the ignition
sequence starts:
The spark generator is energised and delivers a spark to the
main burner and at the same time the main gas valves are
opened.
Once the flame is sensed and proved by the flame detection
probe, the controls keep the main gas valves open until the
control thermostat is satisfied.
The module is protected against blockage of burner, heat
exchanger, flue or fan by the pressure switch. This senses the
differential pressure between the pressure in the fan housing
and the suction in the venturi casting, preventing the ignition
sequence starting or causing safety shut down should the
pressure be outside the design limits. After combustion, the
products flow past the finned aluminium tubes, and through the
gas distribution screen into the boiler casing, transferring heat
to the water flowing through the tubes.
Each module is connected in parallel across the flow and return
water headers, so that water is flowing through all the modules
at all times.

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Super Plus -

Installation and Servicing

Black

Brown

Blue

GENERAL

LEGEND
1. Module electrical plug
2. LED grommets
3. PCB No.9B
4. Control thermostat

potentiometer

5. PCB No.12
6. Flame sensing head
7. Main gas valve leads
8. Fan motor
9. Pressure switch

connections

10. Fan connections
11. Spark/sensing
12. Fan rotor
13. Fan housing
14. Spark generator
15. Overheat thermostat

capillary

16. Main thermostat sensor
17. Lockout reset button
18. Control thermostat knob

Detail of Pressure Switch
Connection (Ref.9)

Fig.2 Module - Exploded View

1. Controls box assembly
2. Fan motor
3. Venturi and gaskets
4. Pressure switch
5. Pressure switch test connections
6. Overheat thermostat pocket
7. Water flow elbow
8. Gas inlet flange
9. Cast iron top cover plate

10. Cast iron top cover plate gasket
11. Aluminium top tube cover
12. Gas distribution screen
13. Aluminium finned tube heat exchanger
14. Aluminium bottom tube plate
15. Bottom cover plate gasket
16. Aluminium bottom cover plate
17. Module lower cover fixing screw
18. Sight glass assembly

19. Main gas line
20. Water return elbow
21. Module thermostat pocket
22. Burner
23. Spark electrode
24. Flame sensing electrode and lead
25. Main gas injector

LEGEND

GENERAL

Fig.3 Electrical Controls - Exploded View

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Super Plus -

Installation and Servicing

Super Plus boilers provide good load-matching sequence control
by the following method:
As the load on the boiler decreases so the return water
temperature increases.
Each module is fitted with an electronic thermostat capable of
being set to within 0.5

C and these thermostats sense the return

water temperature. Once the return temperature reaches 71

the modules are set to switch off at intervals, to maintain the flow
at approx. 82

The modules switch off from left to right and from top to bottom
thus the top left module is always the first to switch off and the
bottom right the last.
The sequence control wiring centre gives a step-start operation
of the boiler.
The modules are allowed to fire only in sequence, starting from
right to left and bottom to top so that the bottom RH module is the
first to fire and the top LH is the last. This step-start prevents
excessive load on gas or electricity supplies.
The wiring centre provides facilities for wiring remote indicators/
alarm of 'Bumer On', 'Lockout' and 'Overheat' for up to 6 modules.
Provision is also made for main supply and direct connection of
any interlock devices such as the water flow system.

INSTALLATION REQUIREMENTS

Failure to install appliances correctly could lead to prosecution. It
is in your own interest, and that of safety, to ensure the law is
complied with.
In addition the installation must comply with the relevant British
Standard Specifications and Codes of Practice, viz;
BS 6880 Part 1-3 Central Heating by Low Pressure Hot Water.
BS 6644

Installation of Gas Fired Hot Water Boilers of Rated
Inputs Between 70kW and 1.8mW (net).

IGE UP/1

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

IGE UP/2

Guidance for Installation of Gas Pipework Boosters
and Compressors for Customers Premises.

IGE UP/10 Installation of Gas Appliances in Industrial and

Commercial Premises.

IM/22

Installation Guide for High Efficiency Condensing
Boilers (Industrial and Commercial Appliances).

Note. The Super Plus is a partially condensing boiler: the
condensate drain should be run in accordance with IM/22.
CP342:2

Centralised Hot Water Supply.

The installation must also conform to current building regulations,
any requirement of the local authority health and safety executive,
gas region, insurance companies and the Health and Safety at
Work Act 1985.
All wiring must conform to IEE (BS7671) Regulations for the
electrical equipment of buildings.

LEGEND

1. Main gas pressure test point

2. Main gas injector

3. Pressure switch electrical leads

4. Pressure switch

5. Pressure switch pressure pipe

6. Pressure switch suction pipe

7. Pressure switch test points

8. Gas manifold flange connection

9. Main gas governor

10. Main gas valve pressure test point

11. Main gas valves

Fig.4 Gas Line - Exploded View

GENERAL

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Super Plus -

Installation and Servicing

6. Flue products must not be allowed to enter the

boilerhouse or adjacent buildings.

7. Refer also BS.6644 and to IGE/UP/10 Installation of Gas

Appliances in Industrial and Commercial Premises and IM/22
for further guidance.

AIR SUPPLY

Detailed recommendations for air supply are given in BS.6644
which MUST be consulted before proceeding.

Contamination of the air supply from any external source must
be avoided - with particular reference to dust, insulation debris,
and flue products and concrete floors must be sealed. If any
work is to be carried out in the boilerhouse which is likely to
generate dust (e.g. structural alterations or lagging pipework), it
is recommended that the boiler be shut down and the modules
covered with a dust sheet, otherwise the boiler may require
cleaning and servicing.

In particular the contamination of the air supply with chlorides
must be avoided as they will cause the deterioration of the
aluminium heat exchanger.

The boiler requires ventilation openings at BOTH high and
low levels, direct from outside, and allowance MUST be
made for stabiliser dilution in all cases.

Mechanically forced ventilation systems must include
provision for boiler shut down in the event of fan failure.

High speed air streams within the boilerhouse must be
avoided.

Extraction mounted ventilation fans alone are NOT permitted.

The minimum effective areas of the permanent air vents
direct from the outside by natural ventilation are as follows:
Required area (cm

) per kW of total rated input (net)

Boiler room

Enclosure

Low level (inlet)

High level (outlet)

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

The minimum air requirements by mechanical ventilation
are as follows:
Table 2

Mechanical ventilation flow rates

Type of boiler

Flow rate per KW total rated heat input (net)

Inlet air

Extract

(Combustion

air

ventilation)

(ventilation)

Forced/induced

2.6 m

1.25m

draught boilers

± 0.18m

A purpose designed flueing ventilation system based solely on a
high level permanent opening to an otherwise sealed boiler-
house or compartment may be used, provided that specialist
advice is taken and that the combustion air and ventilation
requirements of the boiler is provided in line with BS.6644. In
addition this boiler house temperature must be prevented from
exceeding 32

C at mid-level. BS 6644 provides details of

temperature requirements.

LOCATION

The floor must be flat, level and capable of supporting the weight
of the WET boiler pipework. In addition, concrete floors must be
sealed. The siting of the boiler must be in accordance with the
guidance given in BS.6644 and with reference to minimum
boilerhouse clearances - refer to Fig. 5.
Inflammable materials MUST NOT be placed in close proximity
to the appliance. Materials giving off flammable vapours MUST
NOT be stored in the same room as the appliance.

Fig.5 Recommended Boiler House Clearances
for Comfortable Servicing Access (Plan View)

Note: Headroom must be the boiler height
(Table 1) Plus any pipework and flue
requirements

CONNECTION TO GAS SUPPLY

The gas installation MUST be in accordance with the
requirements of the local gas region (refer also to CP 331:3 and
CP 332:3 where applicable).

The gas supply must be capable of maintaining a minimum
pressure as indicated in Table 1, measured at the inlet to the
boiler, with all modules firing (gas consumption is given in
Table 1.) Static inlet pressure should not exceed 50 mb.
The boilers are for use with NATURAL GAS ONLY.

FLUE REQUIREMENTS

Open flue, induced draught and fan diluted systems may be used
but must comply with the following basic requirements:
1. A draught diverter MUST NOT be fitted.
2. A draught stabiliser MUST be fitted to all types of flue systems

and set to control the draught in the casing between neutral
and 0.2 mbar (0.08 in.w.g.) irrespective of flue height or
number of modules firing. (see Figs. 6 and 7 for further
guidance).

3. ALL flue systems must be insulated and/or lined and

impervious to acid condensate. Prefabricated chimneys must
have a 'U' value of no greater than 1.4 W/m

2 o

C at 540

C (0.25

Btu/h ft

2 0

F at 1000

F).

4. Drainage must be provided at the base of the chimney or

liner. (All boiler casings have a condensate drain point - see
Fig. 17)

5. For fan diluted or induced draught systems, air flow/pressure

switches MUST be fitted to protect against fan failure.
Switches should be set to open if the air flow reduces by
more than 15%.

900

(352)

500

(19

)

25(1)

500

(19

)

GENERAL

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Super Plus -

Installation and Servicing

Fig.6 Application of Draught Stabiliser

Fig.7 Flueing - General Guidance

INDUCED DRAUGHT

Note: The discharge from both types of system MUST
not allow recirculation of combustion products into
the boilerhouse or adjacent buildings.

'FAN DILUTED FLUE (FDF)' SYSTEM

Note: Air intake and discharge should be on the same outside wall
face. Design must comply with British Gas requirements - refer P7
and IM/11.

All dimensions in mm (in)

Note: The discharge from both types of
system MUST not allow recirculation of
combustion products into the
boilerhouse or adjacent buildings.

Fig.8 BOILER DIMENSIONS - SUPER PLUS 200/S boiler only

All dimensions in mm (in)

910(35.8)

in.

Gas

connection

in. Water flow Pipe

1420

(55.9)

in.

Flange

Connection

in. Water Return Pipe

600(23.6)

150(5.9)

990(39)

600(23.6)

65(2.6)

25(1.0)

250(10)

165

(6.5)

160(6.3)

1610(63.4)

200

(7.9)

800(31.5)

(0.5)

For 10 in.
Flue Pipe

1400

(55.1)

210

(8.3)

GENERAL

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Super Plus -

Installation and Servicing

WATER CIRCULATION SYSTEM

DESIGN REQUIREMENTS
SUPER PLUS Gas Boilers are intended for use in conjunction
with FULLY PUMPED, OPEN VENTED OR PRESSURISED
systems, subject to the requirements below. They are NOT
SUITABLE for use on gravity circulation systems.
Water flow rate:
28.4 gal/min (2.15 l/s) ± 10% through each module. Thus a 6
module boiler (Super Plus 600/6) requires 170.4 gal/min (12.9 l/
s) volume flow rate.
Note:Failure to maintain this flow rate will result in operation of
the module overheat thermostat.

Any other method of installation should be discussed with
Caradon Ideal Ltd. before proceeding.
Hydraulic Resistance:
When operating at the correct volume flow rate given above, the
Hydraulic Resistance of all Super Plus boilers is 98 mb (39
in.w.g.) ± 20%.
Pump Overrun:
A pump overrun time of 30 seconds minimum must be allowed
for on plant shutdown.

Maximum Static Head:
60.0m (197 ft.), i.e. maximum operating pressure 6.0 bar (85 lb/
in

Minimum Static Head
Minimum static head requirements for open vented systems
must comply with boiler design characteristics, pump
manufacturer's requirements and the requirements of the Health
and Safety Executive Publication PM5.
A minimum static head of 1.6 m is required to overcome the
boiler hydraulic resistance and give a reasonable safety margin.
This requirement is specific to the boiler but installed systems
must also comply with Health and Safety Executive Guidance
Note PM5. In those cases with minimum static head available it
will be necessary to fit a further overheat thermostat in the mixed
flow from the boiler set at 90

C and wired to terminals S2 and S3

in the wiring centre.
Note: In some cases pump manufacturers will require a head
as high as 12 m (40 ft), This must be allowed for the minimum
head increase accordingly.

See Fig.14 for further clarification

1. Roof top or single storey applications

2. Ground floor or basement applications

System Zones
Minimum head
required by boiler,
but additional
head may be
required by the
pump
manufacturer or to
comply with
Health and Safety
Executive
Guidance Note
PM5

All dimensions in mm (in.)

LEGEND
1. Cold feed (size must

comply with BS 6644)

2. Open vent (size must

comply with CP:332:3)

3. Safety valve
4. Water flow switch
5. Dual primary pumps
6. Mixing header
7. Feed expansion tank
8. Mixing valve
9. Highest point in system

Fig.13 Guide to Minimum Requirements - Feed / expansion tank height & boiler primary circuit

HIGH
LEVEL
ZONE

MID
LEVEL
ZONE

HIGH LEVEL ZONE

Super

Plus

Boiler

Super

Plus

Boiler

GENERAL

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Super Plus -

Installation and Servicing

Safety Valve:
A safety valve must be sized and fitted in accordance with BS.6644.
The valve should be set at 0.7 bar (1 0 lb/in

) above the available

static head of water over the boiler.
The maximum safety valve setting is 0.7 bar (10 lb/in

) above the

maximum design operating head of 6.0 bar (85 lb/in

, i.e. 6.7 bar

(95 lb/in

)

Pressure Gauge
The water pressure gauge and temperature gauge must comply
with BS.6644.
Water flow switch
A water flow switch must be fitted to protect the boiler from pump
failure.
Vent, Cold Feed
The open vent and cold feed pipe sizes must comply with BS.6644
and must be of the following minimum size:

The drain valve must comply with BS.2879 and be operated with
a removable key.

GENERAL GUIDANCE ON APPLICATIONS

See Fig.13
Fig.13 is intended to provide basic information only on the
application of the Super Plus Boilers.
It is essential that the water flow rates given above be maintained
within the limits stated. Therefore, any compensating devices
must not be connected to the boilers directly, but may be used in
conjunction with a mixing header. The mixing header must be
sized at least one size larger than the boiler flow and return
manifold size; to avoid hydraulic interference between the boiler
primary pump and system zone pumps.
The use of a mixing header means that compensating controls
can be used to operate mixing valves on a variable temperature
circuit, without affecting the water flow rate through the boiler.
Fig. 14 shows how constant and variable temperature circuit can
be used on low and high head applications.

The following points should be noted:
1. The recommended positions of the cold feed and open vent

are shown, sizes should comply with BS.6644:1986. If
isolating valves are to be fitted in the flow and return pipes of
the boiler they must not isolate the boiler from the open vent,
safety valve or cold feed.

2. The minimum tank height shown is measured from the

highest point of the system and must be increased, if
necessary, to comply with pump manufacturers' requirements.

3. The open vent height above tank water level cannot be

guaranteed adequate in all circumstances and does not take
into account any instantaneous changes in head brought about
by ancillary equipment operating.

4. Water flow switch is shown in its recommended position. It

MUST NOT be located on the mixing header where operation
of zone pumps can cause reduction in flow.

5. Production of condensate: When operating normally and

the design return temperature has reached 70

C the boiler

produces virtually no condensate. At lower temperatures the
amount of condensate increases. It is normal for
condensate to be produced as the boiler heats up from cold
and, provided the time taken for the return to reach 71

C is

not excessive, no harm will result.
If, however, large quantities of condensate are produced for
long periods, this can adversely affect burner performance
and cause the control box to lock out.

If the water contents of a system is very large, it is advisable to
switch on individual zones from cold, in sequence with a time
delay sufficient to allow the boiler return temperature to reach
55

C as quickly as possible.

The condensate drain should be run in accordance with British
Gas Publication IM22.

ELECTRICAL SUPPLY

230 Volt 50 Hz Single Phase A.C.
Consumption:
450 Watts maximum per module (excluding remote alarms, etc.)
Note:
External wiring and any installer supplied remote warning lights
MUST be in accordance with the I.E.E. (BS7671) Regulations
and any local regulations which apply.
The method of connection to the mains supply should facilitate
complete electrical isolation of the boiler.
Connection should be made via a fused double pole switch, or
fused spur box, serving the boiler only and incorporating contacts
with a separation of at least 3 mm in all poles. The point of
connection should be readily accessible and adjacent to the boiler.
The water flow switch and any other overriding safety devices
should be wired in series with the isolation mains supply to the
boiler. Remote indication connections of 'Burner On', 'Lockout'
and 'Overheat are provided in the sequence control wiring centres.
The loads should not exceed 1 amp resistive

GENERAL

Boiler

cold feed

nom.dia(in)

open vent

nom. dia(in)

200/S
300/3
400/4
300/3 alternative
400/4 alternative
500/5
600/6

1 1/4
1 1/2
1 1/2
1 1/2
1 1/2
1 1/2
1 1/2

1 1/2

2
2
2
2
2
2

110531-9.pmd

11/8/2005, 1:03 PM