Potterton Flamingo RS40 Installation and maintenance instructions

Flamingo RS40 and RS50S balanced flue gas fired boiler
INSTALLATION & SERVICE GUIDE
Potterton Flamingo RS40
8.8 to 11.7 kW (30,000 to 40,000 Btu/hr) Output
Potterton Flamingo RS50S
11.7 to 14.7 kW (40,000 to 50,000 Btu/hr) Output
IMPORTANT
This appliance is toy use with Natural Gas only. It must be installed by a competent person as stated in the
Gas Safety (lnstallation and Use Regulations 1984. Leave these instructions adjacent to the gas meter.
Adjustable length, telescopic balanced flue terminal to suit 9 in. to 15 in. thick walls. A kit
(optional extra) is available to increase this to 24 ins.
Infill side panels (optional extra) are available for boilers mounted with exposed sides.
Case Extension Kit is provided (optional extra) to house a pump.
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DATA SECTION – Page 2
GENERALPotterton Flamingo room sealed appliances are auto-matically controlled and have been
designed for combined systems, e.g. small bore or microbore central heating with an indirect domestic hot
water supply which can either have pumped or gravity circulation. These boilers can also be used on a
pumped central heating or domestic hot water only system.
DESCRIPTION See Figure 1 and 3.
The boiler is a slim, space saving appliance which must be installed on the inside of an external wall,
either in a kitchen or utility room or inside a suitably ventilated purpose designed or modified compartment.
The boilers apart from their controls are enclosed in a white, stove enamelled, sheet steel casing. The
controls are mounted beneath the casing in a drawer shaped saluki-bronze cover. Side panels, to blank off
the space between the boiler and the wall are available as optional extras. Also available as an optional
extra, is a casing extension which is fitted on top of the existing boiler casing to enclose a circulating pump
and its pipework.
HEAT EXCHANGER
RS50S
The heat exchanger consists of individual cast iron sections which are jointed with ‘0 rings and bolted
together to form flueways and water-ways. The heat exchanger has flow connections at the top and return
connections at the bottom, located at the rear of the assembly. The boiler thermostat phial is fitted at the
front of the boiler in a pocket screwed into the section. The flue hood, mounted on top of the heat
exchanger, directs the flue gases into the balanced flue ductinq from where the gases are vented to
atmosphere through the terminal on the outside wall of the building.
RS40
The heat exchanger is a single ‘Monobloc’ casting which features two finned flueways and three
waterways, with two flow connections and two return connections. The boiler thermostat phial is located in
a pocket at the front, upper left hand side of the heat exchanger. A flue-hood mounted on the top of the
heat exchanger, directs the flue gases through the boiler backplate into the balanced flue ducting, from
where gases are vented to atmosphere through the terminal on the outside wall of the building.
COMBUSTION CHAMBER AND BURNER
The combustion chamber is a welded rectangular shaped box secured to the under-side of the heat
exchanger. A removable cover on the front of the chamber gives access to the laterally mounted single
bar, aerated main burner. A bracket which supports the right-hand end of the main burner, also mounts the
pilot burner, thermocouple and ignition electrode (on Flamingo RS50S boiler the pilot mounting bracket is
attached to the burner). The combustion chamber has an opening at the top to allow the products of
combustion to pass through the heat exchanger, and another in its rear face to let in fresh air from the air
duct at the rear of the boiler: the air duct connects to the air inlet of the balanced flue terminal.
BOILER CONTROLS
The control system situated at the base of the appliance has been simply designed and is fail safe and
easy to operate. It consists of a multifunctional gas control which includes a thermoelectric flame failure
device controlled from a thermocouple and pilot burner. The main burner is controlled electrically by a
boiler thermostat and a solenoid incorporated into the multifunctional control. Ignition of the pilot burner is
by operation of a Piezo-Electric.
THE SYSTEM See Figures 6 to 10
The boiler can be installed in most types of system but the following notes are given as a general guide.
The general recommendations given in BS. 5376 and BS. 5449 Part 1 should be observed.

1. All system should be designed so that the static head of the boiler is between a minimum 90mbar
(3ft/w.g.) and a maximum. of 2.7bar (9Oft/w.g.), except for fully pumped systems where the cold feed is
connected into the spare return tapping on the boiler in which case, the static head can be reduced to 1
ft/w.g. (For use in flats and maisonettes).
2. If the head is at or near the minimum 90mbar (3tt/ w.g) extra care should be taken when designing the
system to ensure that pumping over or sucking down at the vent pipe cannot occur.
3. All gravity systems should have a minimum effective height of I.2rn (4ft) between the centre line of the
boiler heat exchanger and the centre line of the domestic hot water cylinder
4. Most types of system controls, such as two-way valves, three-way valves, diverter valves, twin pumps,
zone valves and room cylinder and frost thermostats can be used in conjunction with this boiler.
5. It is recommended that an indirect domestic hot water cylinder is used incorporating a coil type of heat
exchanger, In a fully pumped system, the primary pipework should include a lock shield valve.
6. The circulating pump should be selected with reference to Figure 2. The resistance through the boiler
heat exchanger will not exceed 20mbar (8in/w.g.) at a flow rate of 4 gall/mm. for RS40 boilers. For RS50S
boilers the heat exchanger resistance is considerably lower.
7. The resistance through any other type of system control such as a three-way, valve should also be
taken into account when selecting the pump: refer to their manufacturers literature.
8. The circulating pump may be fitted on either the flow or return side of the boiler. If fitted on the flow and
the open vent pipe is located between the boiler and the pump, the risk of air being drawn into the system
is reduced. If fitted on the return, the cold feed pipe should be connected between the pump and the boiler,
but extra care should be taken to ensure that air will not be drawn into the system. Ideally the static head
on the inlet side of the pump should be at least a third of the maximum pump duty.
9. A drain cock(s) should be fitted at the lowest point(s) in the system, so that the whole system can be
drained.
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DATA SECTION – Page 3
FIG. 1 GENERAL ARRANGEMENT
Flamingo RS40 illustrated.
Flamingo RS50S has a sectional heat exchanger.
Page 3

DATA SECTION – Page 4
BOILER MOUNTING SURFACE
The appliance must be mounted on a flat wall of noncom-bustible material which will not reverberate and is
sufficiently robust to take the weight of the boiler. Local Authority and Building Regulations must be observed.
CLEARANCES AROUND THE BOILER
Any position selected for the boiler must give the following minimum clearances for installation and maintenance:
610mm (2ft.) at the front
50mm (2in.) at the top - except where the optional pump casing is to be fitted, when 178mm (7in.) must be allowed.
150mm (6in.) at the bottom
5mm (1/5in.) at each side.
All pipes can be run behind the boiler within its casing width. All connections should be pre-piped with short lengths
of pipe, long enough to clear the extremities of the boiler casing. On the RS4O boiler the flow connection(s) can be
made from above, below or from the left-hand side when viewed from the front: return connection(s) can be made
from above, below or from the right. Connections on the RS5OS boiler can be made from either side to both flow and
return ports, equally connections can be made from above and below the appliance. Pipe-work cannot be run from
left to right behind the boiler, although it can run from one side to the other immediately above or below the air duct,
where in most cases it would be hidden.
VENTILATION
If the boiler is to be installed in a confined space such as a cupboard, the space will need ventilating. Openings should
be provided at the top and bottom of the cupboard, each having a free area of RS5OS 175 sq.cm. (27 sq.in.) RS4O
138 sq.cm. (21 sq.ins.). Where the openings draw air direct from outside the building the size of the free areas can be
halved. Purpose designed, permanent air vents are not required in the room in which the boiler is installed, whether or
not it is in a cupboard. Refer to BS.5376 Part 2 for further information.
Any internal surface of the cupboard that is made of a combustible material and is nearer to the boiler than 75mm
(3ins.) should be insulated as described in British Gas publication Material and Installation Specification for
Domestic Central Heating and Hot Water.
BALANCED FLUE TERMINAL
The correct positioning of the balanced flue terminal on the outside wall of the building is important. It should not be
near any obstruction such as a balcony, drain or stack pipe and it must not be sited near the corner of a building.
Where the terminal has to be positioned near an obstruction, it is advisable to extend the terminal within its limits so
that its grille clears the line of the obstruction: when this is necessary, a false wall should be built around the terminal
box. The terminal must not be located where its discharge could enter an open door or window, on cause a nuisance
in a public right of way. It is advisable to have a minimum of 600mm (2ft.) of flat wall space all around the terminal.
If the terminal discharges at a low level, a terminal guard, supplied, as an optional extra, should be fitted. All
installations should conform with the Local Authority and Building Regulations and British Standard Code of
Practice. BS.5440 Part 1.
ELECTRICAL SUPPLY
A 240 volts A.C., 50Hz single phase electricity supply fused to 3 amperes must be provided in accordance with the
latest edition of the Institute of Electrical Engineers Regulations for the Electrical Equipment and Local Authorities
and British Gas Requirements.
The current rating of the wiring to the boiler must exceed 3 amperes, in accordance with BS.6500 1975 and having a
cross sectional area of at least 0.75 sq. mm. The supply to the boiler and its associated equipment should be
controlled by an unswitched plug and socket or a double pole switch, so that complete isolation from the supply can
be achieved to enable maintenance work to be carried out in safety.
GAS SUPPLY
The gas meter and supply pipe should be checked to ensure that they are large enough for the boiler and any other
appliance already installed; the local Gas Regional Office will assist in this matter. The recommendations of CP. 331
Parts 2 and 3 should be observed.
SAFETY VALVE
If the Local Authorities Regulations stipulate that a safety valve should be fitted, this should be installed in the flow
pipework as close to the boiler as possible.
SERVICING
Servicing is a simple matter as once the casing has been removed all parts that are likely to require servicing are
easily accessible.
SETTING UP
Each boiler has to be adjusted once it is installed and this is a skilled job which should only be undertaken by suitably
qualified Engineers. Potterton International offer this service on a changeable basis.

FIG. 2 PRESSURE LOSS ACROSS BOILER
Page 4
DATA SECTION – Page 5

FIG. 3A CONNECTIONS AND DIMENSIONS RS40
FIG. 3B CONNECTIONS AND DIMENSIONS RS5OS
Page 5
DATA SECTION – Page 6
ADDITIONAL CONTROLS
Potterton Electronic Programmers are available as optional extras. These electronic programmers have been
developed to compliment your boiler and offer the user a variety of programmes to suit individual requirements and
systems. They are attractively styled with a constant digital clock display, slider and push buttons which are easy to
use and understand. This control is fully described in its own Data Sheet which is available on request.
LITERATURE
The following literature is supplied with each boiler:
Data and Installation Instructions/Servicing Guide
Users Guide Card
NOTE: Illustrated parts catalogues for these boilers are available to installers and servicing agents on request to
Potterton International Limited, Brooks House, Coventry Road, Warwick CV34 4LL.
GENERAL DATA
Table 1
RS40 RS5OS
Input 11.6 to 15.2kw
(39,500 to 52,000 Btu/h) 15.6 to 19.2kW (53.000 to 65,500 Btu/h)
Output into Water
8.8 to 11.7kW
(30,000 to 40,000 Btu/h) 11.7 to 14.7kw (40,000 to 50,500 Btu/h)
Output into Air
(approx) 0.7 to 0.9kW (2,400 to 3,100 Btu/h) 0.8 to 0.9kW (2,800 to 3,100 Btu/h)
Water Content 5.6 litres (10 pints) 8.2 litres (1.8 gall.)
Weight (Empty) 75.4 kg (166lb) 77 kg (170 lb)
Burner Pressure 6.0 to 10.5 mbar
(2.4 to 4.2 in.wg.) 10.8 to 16.1 mbar (4.3 to 6.5 in.wg.)
Injector Size 3.35 mm dia. 3.35 mm dia.
Gas Rate 1.12 to 1.47 m3/h
39.5 to 52.0 ft/h 1.5 to 1.85 m3/h 53.0 to 65.5 ft/h
BG.No. 41.601.25 41.601.43
Potterton Code G.T.F. G.T.W.

RS40 RS50S
Max. Working Head: 2.7 bar (9Oft/wg.) Max. Working Head: 2.7 bar (9Oft/wg.)
Main Gas Cock: RC ½ (½in. B.S.P.) loose
key Main Gas Cock: RC ½ (½in. B.S.P.) Loose key
Electrical Connections: 3 - way terminal block on
Electrical Connections: 3 - way terminal block on
control panel control panel
Combination Gas
Control: ½in. B.S.P. Honeywell Com- Combination Gas Control: ½in. B.S.P. Honeywell Com-
pact V4, 600A 1023 pact V4, 600A 1023
Thermostat: Ranco C26 Thermostat: Ranco C26
Main Burner: Furigas Main Burner: Furigas
Pilot Burner: Honeywell Q314A Pilot Burner: Honeywell Q314A
Pilot Ignitor: Vernitron with Buccleugh
Pilot Ignitor: Vernitron with Buccleugh
Electrode Electrode
Page 6
INSTALLATION SECTION – Page 7
INSTALLATION INSTRUCTIONS
The installation of the boiler must be in accordance with the relevant requirements of the Gas Safety Regulations,
Building Regulations, lEE Regulations and the byelaws of the local Water Undertaking.
It should be in accordance also with any relevant require-ments of the local gas region and local authority and the
relevant recommendations of the following British Standard Codes of Practice:
CP 331 Installation of pipes and meters for town gas.
Part 3 Low pressure installation pipes.
BS 5376 Selection and installation of gas space heating (1st and 2nd family gases)
Part 2 Boilers of rated input not exceeding 60kW.
BS 5449 Central heating for domestic premises
Part 1 Forced circulation hot water systems
CP 342 Centralized hot water supply
Part 1 Individual dwellings
Part 2 Buildings other than individual dwellings.
BS 5440 Flues and air supply for gas appliances of rated input not exceeding 60kW (1st and 2nd family
gases)
Part 1 Flues
Part 2 Air supply.
1. UNPACKING
a. The appliance will arrive on-site packed in two cartons as follows:
Carton No. 1
The casing
The air duct
The balanced flue terminal
Controls cover
Accessory screw pack A, B, D, E, F and G
Flue hood attaching parts
Flue hood
Literature
The boiler backplate
Carton No. 2
The boiler assembly and the gas cock.
b. Open Carton No. 1. There is no need to open the boiler carton at this stage.
2. FITTING THE AIR DUCT TO THE WALL-
See Figure 4
a. Decide on the most suitable position for the boiler, taking into account the information given previously, paying
particular attention to the siting of the balanced flue terminal on the outside wall of the building. It is a good idea to
offer the air duct up to the wall and draw a pencil mark around the duct where it will go through the wall.

b. Cut a clearance hole in the wall for the terminal ducting; the size of the ducting is 268mm (10 ½ in.) high and
205mm (8in.) wide.
c. Measure the thickness of the wall, slide the loose air duct ‘A’ into the main air duct ‘B’ and adjust the length to suit
the wall thickness plus 94 mm. Seal the ducting joint with self adhesive tape (supplied) see Figure 4. N.B. The overall
duct measurement X is taken from the rear face of the duct ‘B’ to the front face of duct ‘A’.
d. Temporarily position the boiler air duct against the wall, with its horizontal section inside the wall. Use a spirit
level to ensure that the air duct is square and level.
e. Holding the air duct in its final position, mark the position of the four duct mounting screws on the wall. Remove
the duct from the wall.
f. Drill the four holes and insert wallplugs (accessory pack A).
g. Fit the air duct to the wall, using the screws, flat washers and cup washers provided (accessory pack A).
NOTE: The thickness of the wall plaster in some older properties can be substantial and in these instances, it is
recommended that larger securing screws are used than those supplied.
3. FITTING THE BALANCED FLUE TERMINAL
a. Working from inside and/or outside the building use a suitable sealing material and seal the gap between the duct
and the inside of the hole in the wall; ensure an airtight seal is obtained.
b. Shamfer the plaster sealant as shown in Figure 4 to allow engagement of the balance flue terminal assembly, which
should then be pushed carefully up against the brickwork ensuring that the flanges on the wall plate slide over the
duct retained in the wall. Secure the terminal to the wall with two screws and wall plugs (Accessory Pack B).
c. When applicable, fit the terminal guard, supplied as an optional extra, over the terminal grille and secure it to the
wall.
d. Make good the inside surface of the wall.
4. UNPACKING THE BOILER
a. Open Carton No. 2 containing the boiler.
b. Remove the boiler from its carton and lay it front face onwards on the floor.
c. Remove the two bolts from the rear of the heat exchanger. Fit the backplate to the boiler in its correct position, see
Figure 4 and secure it using the two bolts.
d. Turn the boiler assembly over and remove the four screws securing the combustion chamber front cover; remove
the cover.
5.PREPIPING THE GAS AND WATER CONNECTIONS
-See Figures 3and 3a
The boiler has been designed so that all pipework to its connections can be concealed within its own width. This
enables cupboards to be positioned close up either side with the pipework leaving the boiler at the top and/or bottom
as required.
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Installation Section – Page 8
Because the pipework connections are behind the boiler backplate, short lengths of pipe should be connected to the
appropriate tappings before the boiler is lifted into position, and terminated just clear of the boiler for connecting to
the system pipework. It is recommended that capillary fittings are used.
FIG. 4 MOUNTING FEATURES
(Flamingo RS4O illustrated)
Page 8
Installation Section – Page 9
A Combined Gravity System
RS5OS
1. Connect a suitable length of 28mm pipe with 90º elbow to either the R.H. or L.H. 1" B.S.P. rear facing flow
connections. (Hot water)
2. Connect a suitable length of 22mm pipe with 90º elbow to the remaining 1" B.S.P. rear facing flow connection.
(Central heating)
3. Connect a suitable length of 28mm pipe with 90º elbow to either the R.H. or L.H. 1" B.S.P. rear facing return
connections. (Hot water)

4. Connect a suitable length of 22mm pipe with 90º elbow to the remaining 1" B.S.P. rear facing return connection.
(Central heating)
NOTE: Ensure that the fittings at the rear of the boiler do not protrude more than 92mm from the boiler backplate or
they may foul the wall.
RS4O
1. Connect a suitable length of 28mm pipe to the 1 in. B.S.P. upwards facing domestic hot water flow connection on
top of the heat exchanger.
NOTE: The flow pipe must be turned through 90º and routed through the cut-out in the back-plate, ensuring it is kept
within the confines of the cut-out. It must not project above or to the side of the backplate, otherwise it will be
impossible to fit the casing.
2. Connect a suitable length of 22mm pipe to the ¾ in. B.S.P. rear facing central heating flow connection. There is
room to split the flow behind the boiler if required. The circulating pump can be fitted on either the flow or return,
above or below the boiler; refer to ‘The System’, and the pump manufacturers instructions.
3. Connect a suitable length of 28mm pipe to the upper 1in domestic heating return connection.
4. Connect a suitable length of 22mm pipe to the lower 1in. central heating return connection.
NOTE: Ensure that the fittings to the return connections do not protrude more than 92mm from the boiler backplate,
or they may foul the wall.
B Fully Pumped System or Pumped Central Heating Only
RS5O
1. Connect a suitable length of 22mm pipe with elbow to either the R.H. or L.H. 1in B.S.P. rear facing flow
connections. The vent pipe should be connected into the flow pipe as close to the boiler as possible. Blank off the
remaining flow connection.
2. Connect a suitable length of 22mm pipe with elbow to either the R.H. or L.H. 1in B.S.P. rear facing return
connections.
3. The remaining connection can be blanked off or used to connect the cold feed.
4. The circulating pump can be fitted in any position on either the flow or return to suit the particular installation.
Refer to ‘The System’ and ‘Pump Manufacturer’s Instructions’.
RS4O
1. Connect a suitable length of 22mm pipe to the 1in B.S.P. upwards facing combined flow connection on top of the
heat exchanger. The vent pipe should be connected into the flow pipe as close to the boiler as possible. Blank off the
¾ in. B.S.P. rear facing flow connection. If it is necessary to use this ¾ in. B.S.P. flow connection a 22mm pipe
should be connected to it and the 1in. B.S.P. connection used for the vent pipe.
NOTE: The flow pipe must be turned through 90º and routed through the cut-out in the back-plate, ensuring it is kept
within the confines of the cut-out. It must not project above or to the side of the backplate, otherwise it will be
impossible to fit the casing.
2. Connect a suitable length of 22mm pipe to the lower 1in return connection.
3. The upper 1in return connection can either be blanked off or used to connect the cold feed.
4. The circulating pump can be fitted in any position on either the flow or return to suit the particular installation.
Refer to ‘The System’ and the ‘Pump Manufacturer’s Instructions’.
C Boiler Main Gas Cock
1. The main gas cock is supplied loose and must be fitted directly to the union nut and liner already assembled to the
inlet pipework on the boiler. The gas cock must be located in the most suitable position for operation, e.g. with its
operating plug facing towards the side of the boiler.
2. Connect a suitable length of 15mm pipe to the gas cock, terminating it in a length which can be easily connected to
the main supply, once the boiler is in position on the wall.
6. FITTING THE BOILER ON THE WALL
a. Stand the boiler on the floor in a vertical position, so that it is supported on its two metal legs. Lift the boiler onto
the air duct on the wall, locating the hook at the top of the boiler backplate, over the top edge of the duct.
b. Secure the boiler backplate to the air duct with the four screws adjacent to the flue hood position (Accessory Pack
D). Secure the combustion chamber to the air duct with the four screws with washers (Accessory Pack E), inside the
combustion chamber.
NOTE: Accessibility for fitting the four screws inside the combustion chamber will be improved if the main burner is
first removed.
c. Fit the fluehood to the boiler, using tie-rods which located either into holes in the back plate RS40 or holes in the
return edge of the backplate RS50S and angle strap, see Figure 4, securing it with the two nuts and washers
(Accessory Pack F); ensure an air tight seal is obtained between the fluehood, the top of the heat exchanger and the
backplate.
d. Fit the combustion chamber front cover, securing it with the four screws; ensure a gas tight seal is obtained.

e. Undo the capillary coil of the thermostat and teed phial into thermostat pack in H.E. Ensure that routing of
capillary is clear of the case.
f. Connect the main gas supply to the length of pipe fitted to the boiler main gas cock. Ensure that the tap is in a
position suitable for its operation.
Page 9
Installation Section – Page 10
g. Connect the short lengths of pipe, previously fitted to the water flow and return connections, to the system
pipework.
h. Open all water valves and thoroughly flush the system.
i. Fill and vent the water system and test for leaks, rectify if necessary.
j. Unscrew the nuts and remove and discard the two metal legs at the bottom of the boiler.
7. WIRING - See Figures 5to 11
Care must be taken to ensure that all wiring to the boiler is kept clear of sharp edges and hot surfaces.
The boiler terminal strip is not designed to accept wiring from all the on-site system controls and therefore, the
installer will need to incorporate a suitable junction box. The principle of wiring the boiler and its controls is shown
in Figure 5. However, the layout of a particular system will itself govern the most economical location for the
junction box and its terminals.
FIG. 5 PRINCIPLE OF WIRING
Wire the boiler and system controls as illustrated in
Figures 7,8,9, 10 and 11 depending on the type of system installed. The wiring arrangements shown outline
only the basic control requirements, and will therefore require on-site interpretation of the various boiler
installation arrangements.
Figure 10 illustrates a system with a zone valve which requires an electrical supply to motor it both to the open and
closed positions. Zone valves which require an electrical supply to open them but not to close them, should be wired
in a similar manner but ignoring the closed connection from the room thermostat. For this type of valve, a room
thermostat with a single pole contact should only be used. Certain zone valves may require an additional connection
to the auxilIary switch (shown dotted). This would apply to those valves which internally are not suitable for giving
an open signal from the normal opening voltage supply.
If a Potterton EP 2000/3000 Programmer time control is not being fitted, but a three terminal time clock is to be
installed to control the systems illustrated in Figures 7,8,9, l0 or 11 the time clock should be wired as follows:
Live to Time Clock Live
Neutral to Time Clock Neutral
Earth to Time Clock Earth
Wires normally connected to EP 2000/3000
Programmer Terminals 3 and 4 to Time Clock Switch
A low limit thermostat can be installed to override the ‘OFF’ setting of the time control. Where an EP 2000/ 3000 or
equivalent Programmer is installed, a double pole thermostat or a single pole thermostat with change over contacts
may be necessary; for the electrical connections and type required, see the relevant system wining diagram. Where
only a time clock is fitted, the thermostat need only be a single pole type with its contact wired in parallel with the
clock switch.
If a three way (proportioning diverter) valve with a mid-position is being fitted in the system, the following
instructions must be adhered to in addition to the valve manufacturers wiring information.
1. Neutral and earth connections must be made to boiler terminals N and E.
2. The switches supply from the system control circuit must be connected to boiler terminal L.
3. The live supply to the pump must be taken from the supply to boiler terminal L.

FIG. 6 BOILER WIRING DIAGRAM
Page 10
Installation Section – Page 11
FIG 7 GRAVITY HOT WATER WITH PUMPED CENTRAL HEATING

FIG 8 GRAVITY HOT WATER WITH TEMPERATURE CONTROLLED AND PUMPED CENTRAL
HEATING

Page 11
Installation Section – Page 12
FIG 9 FULLY PUMPED WITH TWO POSITION DIVERTER VALVE
NOTE: The minimum 900mm (3ft.) static head shown in figs. 9, 10 and 11, and mentioned in Section 1 in ‘The
System’ on page 2, can be reduced to 300mm (1ft.) providing the cold feed is connected directly into the spare
return tapping on the boiler. A static head of less than 300mm (1ft.) should not be used.

NOTE: These system diagrams, figs. 7to 11, are schematic only. Installers are recommended to read "The
System" on page 2 and BS5376 and BS.5449 Part 1.
FIG 10 FULLY PUMPED WITH ONE OR TWO TWO-WAY VALVES
Page 12

Installation Section – Page 13
FIG. 11 FULLY PUMPED USING TWO PUMPS
8. FIRST LIGHTING
Before lighting the boiler, the gas installation must be tested for soundness in accordance with CP331 Part 3 1974.
The electrical installation must be checked as follows:-
8.1 PRELIMINARY ELECTRICAL SYSTEM CHECKS See Figures 6and 12
A. Earth Continuity Check - appliance must be electrically connected - meter set on Ω (ohms) x 1 scale and
adjust to zero if necessary.
a) Test leads from any appliance earth point to earth pin on plug resistance should be less than 1 Ω (ohm).
If the resistance is greater than 1 Ω (ohm) check all earth wires for continuity and all contacts clean and tight.
If resistance of earth is still greater than 1 Ω (ohm) then this should be reported to your supervisor.
B. Short Circuit Check - appliance electrically disconnected, all switches ON including stats.
a) Meter set on Ω (ohms) x 1 scale.
Test leads from L to N in appliance terminal strip/ block - if meter reads ‘0’ then there is a short circuit.
b) Meter set on Ω (ohms) x 100 scale.
Repeat test with leads from L to E. If meter reads less than ∞ (infinity) there is a fault.
NOTE: Should it be found that the fuse has failed but no fault is indicated - a detailed continuity check (i.e. by
disconnecting and checking each component) is required to trace the faulty component. It is possible that a fault could
occur as a result of local burning/arching but no fault could be found under test. However, a detailed visual inspection
should reveal evidence of burning around the fault.

Page 13

Installation Section – Page 14
C. Polarity Check
Appliance connected to mains supply and meter set of 300 Vac scale. Test at appliance terminal strip:-
a) Test leads from L to N - meter reads approx. 240 Vac
b) Test leads from L to E - meter reads approx. 24OVac
c) Test leads from N to E - meter reads from 0.15Vac
Thus the terminal marked L is the live terminal. If the low Vac reading is given on terminals other than N to E
there is an electrical fault.
Repeat the test at the appliance plug/inlet spur to check the wiring system up to the appliance and rectify any fault. If
necessary repeat the test at the supply system socket/spur - if the fault also occurs at this stage then there is a house
system fault which requires attention by the Electrical Authority. The customer should be warned not to use the
appliance until this examination has been carried out.
D. Resistance to Earth Check
Appliance must be disconnected from mains supply and meter set on Ω (ohms) x 100 scale. All switches
including stats, ‘On’ - Test leads from L to E - if meter reads other than infinity (∞) there is a fault which
should be isolated. A detailed continuity check is required to trace the fault component.
IMPORTANT
This series of checks are the first electrical checks to be carried out during a fault finding procedure. On completion
of the service/fault finding task which has required the breaking and remaking of electrical connections then the
checks A. Earth Continuity, C. Polarity and D. Resistance to Earth must be repeated.
8.2 TO LIGHT THE BOILER
a) Fit the boiler thermostat knob (Accessory Pack G) onto its spindle and switch it to the off position.
b) Check that the main electricity supply to the boiler is switched on.
c) Turn on the main gas supply.
WARNING: OPEN ALL WINDOWS AND EXTINGUISH ANY NAKED LIGHTS IN THE ROOM AND PUT
OUT PIPES AND CIGARETTES.
d) Break the union adjacent to the boiler main inlet cock, then open the cock and purge any air from the supply pipe.
e) Close the cock, remake the union then re-open the cock and test for gas soundness using a soap solution.
WARNING: DO NOT USE A NAKED FLAME
f) Ensure that the system is full of water and that the pump and radiator isolating valves are open.
g) Ensure that the time control, if fitted, is in an ‘on’ condition, and that the room and/or cylinder thermostats, where
fitted, are set to high temperatures.
h) Turn the control button on the gas control valve clockwise as far as possible (approximately 1/12th of a turn) and
release it. This ensures the valve is in the off condition.
I) Press and hold in the control button on the gas control valve, then press in the igniter button until
a click is heard. Release the igniter button but continue to hold in the control button and check through the sight hole
that the pilot has lit: hold in the control button for a further 20 seconds, then release it and the pilot should remain
alight.
NOTE: On first lighting, establishment of the pilot flame may be slightly delayed due to the presence of air in the
pipework and several operations of the igniter button may be necessary.
If the pilot fails to light or goes out at any time, immediately turn the control button clockwise as far as possible
(approx. 1/12th of a turn), then release it and wait three minutes before repeating the lighting procedure. The control
button should not be touched during this period.
k) Turn the boiler thermostat on and to a high setting and the main burner will light.
I) Set the boiler thermostat and the room and/or cylinder thermostat(s) and time control, where installed, to their
required operating conditions.
9. FINAL ADJUSTMENT
A. Gas Rate and main burner pressure setting
1) Fit a pressure gauge to the pressure test nipple on the gas control valve, see Figure 1.
2) Turn on the boiler thermostat, then check that the burner pressure is in accordance with Table 1.
3) If burner pressure adjustment is necessary, remove the screwed cap on the top of the control valve and turn the
screw beneath clockwise to increase pressure or anti-clockwise to decrease. Re-fit the screwed cap when the pressure
is correct. Shut down the boiler, remove the pressure gauge and tighten the screw in the pressure test nipple.
4) With the burner set to its correct pressure, the firing rate given in Table 1 should also be obtained and this should
be checked by meter reading over a period of at least five minutes once the boiler is hot.
B. Pilot Burner

The correct adjustment is achieved when the length of the pilot flame completely envelops the tip of the
thermocouple, but the tip itself is still visible. See Figure 13.
When the pilot is set to the above instructions the E.M.F. generated by the thermocouple should be of the order of 18
- 32 my open circuit, 10 - 15 my closed circuit. Drop out should occur between 2 -4 my closed circuit.
C. Boiler Thermostat
1) At its maximum and minimum settings, the thermostat should control the water flow temperature at approximately
55ºC - 80ºC (130º - 182º F) respectively. This should be checked using preferably a thermometer in the flow pipe or
alternatively a ‘clip-on’ type if one is not fitted.
2) The thermostat has been calibrated by the makers and no attempt should be made to recalibrate it on site. Turn the
thermostat to the off position and check that the main burner shuts down.
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Installation Section – Page 15
D. Combined Control
Solenoid
Check the operation of the valve by turning off the electricity supply, either by the isolating switch or the time
control, where installed. The main burner must shut down immediately.
Flame Safety Valve
Check the operation of the valve as follows with the boiler running normally: - Turn the control button clockwise as
far as possible and a distinct click should be heard within 60 seconds indicating that the flame failure valve has
closed.
E. Remote Controls
Check that any other remote control connected in the system such as time clocks and thermostats, control the boiler
as required.
10. CASING
NOTE: Ensure that the electrical supply to the boiler is switched ‘off’.
A. Fit the casing to the boiler, locating the tongue inside the casing top, into the trough on the air duct bracket. Secure
the case with the two captive screws at its lower edge, and the single captive screw at the top, adjacent to the locating
tongue.
B. Remove the thermostat knob, then fit the controls cover in position and secure it with the captive screw. Refit the
thermostat knob.
NOTE: The panel on the front of the controls cover, through which the thermostat spindle and the control and igniter
button protrude, can be adjusted by a simple sliding action to line up with the controls.
11. USER’S GUIDE
A user’s guide is provided with this boiler but if possible, the installer should explain the operation of the boiler and
system to the householder.
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SERVICE SECTION – Page 16
SERVICE INSTRUCTIONS
To ensure continued efficient operation of the boiler it is necessary to carry out maintenance and cleaning
at regular intervals.
The frequency of cleaning will depend upon the particular installation conditions and the use to which the
boiler is put, but in general, once per year should be adequate.
Before the start of any maintenance, switch off the main electricity supply and disconnect the plug at the
main isolating switch and socket. Turn off the boiler main gas inlet cock.
If there has been any delay in cleaning, and the boiler has been switched off, it is desirable to operate the
boiler for a short time to dry out deposits in the flueways which, if they are left in the cold state, will absorb
moisture and become both corrosive and difficult to remove.
The following notes apply to the boiler and its controls, but it should be remembered that attention must
also be paid to the heating circuit itself including radiator valves, thermostats, the time control and the
expansion and feed water system. In all cases prior to maintenance, light up the boiler and check that the
pilot and main burners have a clean, even flame and that the gas rate and main burner pressure is-
correctly set.
NOTE:
Where it is required to break any seal during maintenance, the seal should be examined carefully for
damage and if necessary replaced. It is important to obtain the correct Potterton approved part for the seal