andrews RSC 190 User manual

Natural Gas Fired
Storage Water
Heaters
Room Sealed
Appliance
MODELS
RSC 150
RSC 190
INSTALLATION
GUIDE,
OPERATION
AND SERVICE
MANUAL
THIS MANUAL MUST BE KEPT WITH THE APPLIANCE
Part No. E104

© Copyright Andrews Water Heaters 2005
Reproduction of any information in this publication by any method is not permitted
unless prior written approval has been obtained from Andrews Water Heaters.
Andrews Storage Water Heaters have been designed and manufactured to comply
with current International standards of safety. In the interests of the health and
safety of personnel and the continued safe, reliable operation of the equipment,
safe working practices must be employed at all times. The attention of U.K. users is
drawn to their responsibilities under the Health and Safety Regulations 1993.
All installation and service on the Andrews Water Heater must be carried out by
properly qualified personnel, and therefore no liability can be accepted for any
damage or malfunction caused as a result of intervention by unauthorised
personnel.
The Andrews Water Heaters policy is one of continuous product improvement, and
therefore the information in this manual, whilst completely up to date at the time of
publication, may be subject to revision without prior notice.
Further information and assistance can be obtained from:
Andrews Water Heaters
Wednesbury One, Black Country New Road
Wednesbury, West Midlands WS10 7NZ
Tel: [phone] Fax: [phone]
Email: [email protected]
Website: www.andrewswaterheaters.co.uk
THE ANDREWS WATER HEATERS COVERED IN THIS MANUAL
ARE FOR USE WITH NATURAL GAS ONLY

CONTENTS
SECTION 1 GENERAL AND SAFETY INFORMATION
General Information 2
British Standards and Codes of Practice 2
Health and Safety Regulations 1993 3
Effectiveness in Combating Legionellae 3
SECTION 2 TECHNICAL DATA 4
SECTION 3 INSTALLATION
Location 5
Flue Systems 5
Air Supply and Ventilation 6
Water Connections 8
Water Quality & Treatment 8
Hydrojet Systems 8
Vented Systems 9
Unvented Systems 10
Gas Connections 13
SECTION 4 COMMISSIONING
To Light the Burner 14
To Shut Off the Burner 14
To Check Main Burner Pressure 14
SECTION 5 OPERATION
Operating Sequence 15
ECO (Energy Cut-Off) 15
SECTION 6 SERVICING
Burner Assembly 16
Gas Control Valve 16
Flueway 17
Magnesium Anode 17
Descaling Information 17
SECTION 7 FAULT FINDING 18
SECTION 8 PARTS LISTS AND ILLUSTRATIONS 19
PAGE

GENERAL AND SAFETY INFORMATIONSECTION 1
The Andrews Water Heater has been designed for use with NATURAL GAS only and is
manufactured to give an efficient, reliable and long service life.
To ensure the continued, trouble-free operation of your heater at maximum efficiency, it
is essential that correct installation, commissioning, operation and service procedures are
carried out strictly in accordance with the instructions given in this manual. By law,
installation and commissioning of the heater must be carried out by properly qualified
personnel.
The heater(s) must be installed in accordance with the following requirements;
The current GAS SAFETY (INSTALLATION AND USE) REGULATIONS
The current BUILDING REGULATIONS
The WATER SUPPLY (WATER FITTINGS) REGULATIONS 1999
Additionally, installation should be performed in accordance with all relevant
requirements of the Gas Supplier, Local Authority and recommendations of the British
Standards and Codes of Practice detailed below.
STANDARD RANGE
BS 6700: 1997 Specification for design, installation, testing and maintenance of
services supplying water for domestic use within buildings and their
curtilages. This standard supersedes the following British Standards
and Codes of Practice: CP99, CP310, CP324, 202, CP342 Part 2,
Centralised Hot Water Supply.
BS 5440:1990 Installation of flues and ventilation for gas appliances of rated output
not exceeding 60kW.
BS 6644 Installation of gas fired hot water boilers of rated inputs between
60kW and 2MW.
BS 5546:1990 Installation of gas hot water supplies for domestic purposes.
BS 6891 Installation of low pressure gas pipework of up to 28mm in domestic
premises.
BS 7206:1990 Specification for unvented hot water storage units and packages.
I/M2 Purging procedures for industrial and commercial gas installations.
I/M11 Flues for commercial and industrial gas fired boilers and air heaters.
I/M16 Notes on installation of gas pipework (excluding 25mm and below).
BS 6798 Installation of gas fired hot water boilers of rated input not
exceeding 60kW.
NOTE: Consideration should be given to amendments or updates to
the above standards.
GENERAL
INFORMATION
BRITISH
STANDARDS
AND CODES OF
PRACTICE
2

GENERAL AND SAFETY INFORMATION SECTION 1
It is the duty of manufacturers and suppliers of products for use at work to ensure, so far
as is practicable, that such products are safe and without risk to health when properly
used and to make available to users, adequate information about their safe and proper
operation.
Andrews Water Heaters should only be used in the manner and purpose for which they
were intended and in accordance with the instructions in this manual. Although the
heaters have been manufactured with paramount consideration to safety, the basic safety
precautions highlighted in this manual must be observed by the user.
It is imperative that all users of the heater must be provided with all the information and
instruction necessary to ensure correct and safe operation.
Water systems in buildings have been associated with outbreaks of Legionnaires' Disease,
particularly in health care facilities where occupants are significantly more susceptible to
infection.
In recognition of the risks in hospitals, a Code of Practice for the Control of Legionellae
in Health Care premises has been issued by the Department of Health (1991). Codes of
Practice applicable to other premises have been published by other organisations,
principally the Health and Safety Executive (HS)(G70) and the Chartered Institute of
Building Services Engineers (C1BSE, TM13).
All Codes of Practice draw attention to the design and operation of water systems with
reference to avoidance of factors that favour colonisation by Legionellae bacteria. These
factors include stagnation, lukewarm conditions (20ºC to 45ºC) and the accumulation of
debris, scale and corrosion in the base of tanks and calorifiers.
Andrews Water Heaters has commissioned an independent evaluation of their products
to investigate their resistance to build-up of legionellae bacteria.
Experiments were conducted to determine whether, following a substantial challenge by
legionellae pneumophilia, after overnight and stagnation conditions, the system was
rendered free from viable recoverable legionellae. It was found that at 61ºC, following a
challenge of approximately 107 organisms per litre, within one hour, more than 99.999%
of organisms had been killed. After a subsequent stagnation period, sampling did not
reveal any residual contamination. The design of the base of the water heater precludes
legionellae colonisation, even after build-up of debris. The burner positioning ensures
that the water at the bottom of the heater reaches the same, or higher temperature as in
the rest of the heater.
Based on data obtained through experiment, the Andrews Water Heater can be described
as legionellae resistant as it is considered unlikely that, at the temperature tested, the
organism would colonise the water heater and present a possible health risk.
HEALTH AND
SAFETY
REGULATIONS
1993
EFFECTIVENESS
IN COMBATING
LEGIONELLAE
3

TECHNICAL DATASECTION 2
DIMENSIONS
AND
CLEARANCES
4
SI Metric Imperial SI Metric Imperial
A Height of Heater 1264 mm 493⁄4 in 1492 mm 583⁄4 in
B Diameter 508 mm 20 in 508 mm 20 in
C Gas Connection 378 mm 147⁄8 in 378 mm 147⁄8 in
D Height to Centre of Flue 2118 mm 831⁄2 in 2346 mm 921⁄2 in
E Service Clearance 1226 mm 48 in 1226 mm 48 in
F Standard Flue Run 750 mm 291⁄2 in 750 mm 291⁄2 in
G Height to Flue Centre 854 mm 331⁄2 in 854 mm 331⁄2 in
H Standard 90ºElbow 194 mm 75⁄8 in 194 mm 75⁄8 in
I Service Clearance 305 mm 12 in 305 mm 12 in
J Service Clearance (Front) 610 mm 24 in 610 mm 24 in
K We recommend that the flue outlet can be installed in any configuration through 180ºas long as proper service clearances are observed.
Storage Capacity 150 litres 33 gallons 190 litres 42 gallons
Recovery through 44˚C/80˚F 159 l/hr 35 gph 181 l/hr 40 gph
Recovery through 56˚C/100˚F 127 l/hr 28 gph 145 l/hr 32 gph
Heat Input 9.5 kW 32,414 Btu/hr 10.5 kW 35,826 Btu/hr
Heat Output 8.2 kW 27,978 Btu/hr 9.4 kW 32,073 Btu/hr
Gas Flow Rate 0.01 m3/min 0.522 ft3/min 0.02 m3/min 0.577 ft3/min
Gas family I2H Natural I2H Natural
Flue Gas Temp Approx 180ºC 180ºC
Flue Gas Volume 16m3/H 16m3/H
Inlet & Flow connections Rp 3⁄43⁄4BSP Rp 3⁄43⁄4BSP
Return connections Rp 3⁄43⁄4BSP Rp 3⁄43⁄4BSP
Gas Connection Rp 1⁄21⁄2 BSP Rp 1⁄21⁄2 BSP
Maximum Working Pressure 10 bar 150 p.s.i. 10 bar 150 p.s.i.
Maximum Test Pressure 20.6 bar 300 p.s.i. 20.6 bar 300 p.s.i.
Burner Pressure 10.0 mBar 4.0 wg. 10.0 mBar 4.0 wg.
Injector Diameter 2.87 mm 0.113 ins 3.05 mm 0.120 ins
Flue Connection 80/125 80/125
Weight Empty 66 kg 145 lbs 74 kg 163 lbs
Weight Full 216 kg 475 lbs 264 kg 583 lbs
Shipping Weight 73 kg 162 lbs 82 kg 181 lbs
Shipping dimensions carton 1499 x 635 x 711 mm 59 x 25 x 28 in 1727 x 635 x 711 mm 68 x 25 x 28 in
ANDREWS MODEL NO. RSC 150 RSC 190
Recommended Service Clearance
Recommended Service Clearance
G
K
J
180˚
I
HF
E
A
B
D
C
Concentric Flue
External Flue diameter 125mm (5”)
Internal Flue diameter 80mm (3”)
Recommended Service Clearance
Minimum Service Clearance
Fig 1.
Appliance Dimensions
Including
Standard Flue Run
Dimensions

INSTALLATION SECTION 3
5
Detailed recommendations for flueing are given in British Gas Booklet IM/11 and
BS 5440 part 1. The following notes are intended to give general guidance:
•A horizontal or vertical flue kit is supplied with each heater. Flue fitting instructions on
page 6.
•Location. The siting of the flue terminal is not critical with respect to the performance of
the unit. However, areas where the discharge of combustion products would cause a
nuisance should be avoided. In accessible positions a suitable guard should be provided.
(see page 6).
•Route. The route of the flue is not critical, with three installation options available. See
below for permissible flue lengths. Where installation options 2 or 3 are used we
recommend that the flue outlet can be installed in any configuration through 180ºas
long a proper service clearances are observed see fig.1 page 4.
THE LAW REQUIRES THAT INSTALLATION IS CARRIED OUT BY A PROPERLY QUALIFIED PERSON
Install in accordance with current British Standard Code of Practice 342 part 2 and British
Standards 5440, 5546, 6644, 6700, 6798 and 6891.
The location chosen for the heater must permit the provision of a satisfactory flue and an
adequate air supply.
A clearance of 3OOmm (l2in) should be left around the heater for fitting and servicing
purposes and 762mm (3Oin) above the heater for removal of the flue baffle. The above
clearances are recommended for ease of servicing. They can be reduced if necessary but a
clearance of 3OOmm (12 in) must be left in front of heater for access to the burner and
controls. The flue baffle clearance should also be maintained if possible to avoid servicing
problems.
The floor on which the heater is installed must be flat, level and of sufficient strength to
withstand the weight of the heater when filled with water, and should satisfy the
requirements of the Local Authority & Building Regulations.
Any combustible material adjacent to the heater must be so placed or shielded as to ensure
that its temperature does not exceed 66°C (150°F).
Flueing Option Installation 1 Installation 2 Installation 3
Type of flueing C31 C31 C11
Flue restrictor Ø45mm Ø50mm Ø60mm
A≤2.0 - ≥0.5m and ≤1.0m
B-≤1.0m ≤1.0m
Model RSC150
Flueing Option Installation 1 Installation 2 Installation 3
Type of flueing C31 C31 C11
Flue restrictor Ø48mm Ø55mm no restrictor required
A≤2.0 - ≥0.5m and ≤1.0m
B-≤1.0m ≤1.0m
Model RSC190
A
500mm
500mm
600mm
B
Wall
B
A
1.2 Mtrs.
3.2 Mtrs.
Roof
Installation 1 Installation 2 Installation 3
Fig 2.
Typical Flue
Installations and
Permissable Flue
Lengths
LOCATION
FLUE SYSTEM

The following notes are intended to give general guidance:
Where the heater is to be installed in a room NO VENTS ARE REQUIRED.
Where the heater is to be installed in a compartment, permanent air vents are required in
the compartment at high and low level. These air vents must either communicate with a
room or internal space or be direct to outside air.
The minimum effective areas of the permanent air vents required in the compartment are as
follows:
INSTALLATIONSECTION 3
Components
Supplied In Flue Kits
AIR SUPPLY
AND
VENTILATION
6
D7
D8
D2
D4
D3 D10
D9
D6
D6
D1
D5
RSC150 & RSC190 Flue Fitting Instructions
1. Fit heater adaptor D1 to heater ensuring correct location on primary flue spigot from
heater. (Use 4 self tapping screws provided).
2. Fit flue restrictor ring D7 into heater adaptor D1 The correct size of restrictor for
each heater model and installation is shown on page 5.
3. Fit flue section D2 into heater adaptor D1.
4. Fit elbow D4 into flue section D2 for horizontal flue runs.
5. Determine correct position of flue outlet and fit outer wall plate and inner wall plate.
Fit flue outlet guard if required. (Fixings not supplied).
6. Fit horizontal terminal D3 or make up lengths of flue required (see page 5) into
elbow D4. Each joint must be secured with a sealed clamp D6.
7. For vertical installations fit flue lengths required (see page 5) into heater
adaptor D1.
8. Determine correct position of flue terminal and fit either D8 or D9 roof plates.
9. Fit D5 vertical terminal through roof plate into vertical flue pipe.
10. Fit D6 sealed clamps on all joints.
11. On all installations the lengths of flue pipes may be cut to obtain correct length of
flue route required.
12. See parts list on page 20 for part numbers and description of flue available.
Air Vents Areas
Position of Air from room or Air direct from
Air Vents internal space outside
High Level 10cm2per kW 5cm2 per kW
Low Level 10cm2per kW 5cm2 per kW
In a Room or
Internal Space No requirement for ventilation

INSTALLATION SECTION 3
Note: - Both air vents must communicate with the same room or internal space or must
both be on the same wall to outside air.
Air vents should have negligible resistance and must not be sited in any position where they
are likely to be easily blocked or flooded or in any position adjacent to an extraction system
which is carrying flammable vapour.
Consideration must be given to the position of the high level ventilation opening. A high
level vent must not be sited within 300mm measured vertically, of the flue terminal
Grilles or louvers should be so designed that high velocity air streams do not occur within
the space housing the heater(s).
IMPORTANT:
The vapours given off by halogen based compounds can, if drawn into the combustion air,
cause corrosion of the Storage Vessel and premature failure of the thermocouple.
If water heaters are to be installed, in locations where halogens are likely to be present they
should be isolated from such compounds and ventilated from and to outside,
uncontaminated atmosphere.
Some of the vulnerable areas are listed below -
(i) Hairdressing salons and adjoining rooms and basements.
(ii) Establishments where dry cleaning solutions are used or stored.
(iii) De-greasing plants using hydrocarbon solvents.
(iv) Premises where refrigerant gases are used or stored.
7

To ensure long life and efficient, reliable performance from Andrews water heaters it is
essential that the water heater is installed and serviced in accordance with the
manufacturers instructions.
Each water heater is fitted with one or more magnesium anode(s) which protect the tank
from corrosion caused by electrolytic action within water systems. The magnesium
anodes are sacrificial and as such they erode as they offer protection. Once the anode
has eroded to less than 50% of its original diameter it may not offer sufficient protection.
The anodes should be inspected on an annual basis and replaced as necessary. The
frequency of which the anode needs replacing can vary and water quality can have a
major influence on this.
Andrews offer Correx™UP powered anodes as an alternative to the traditional
magnesium anodes. Correx™UP anodes are made from titanium and are non sacrificial,
therefore they do not have a requirement for maintenance or replacement. However, the
potentiostat, which regulates the protective current supplied to the Correx™UP anode,
has an indicator light which shows green when the anode is functioning correctly and red
if a malfunction occurs.
Correx™UP anodes are available as an optional extra on all models of Andrews storage
water heaters and tanks.
In hard water areas scale formation can occur in hot water systems and water heaters
and the higher the temperature of operation and the higher the volume of water used
the more problematic this scale build up can be. Water treatment is normally
recommended when the hardness reaches 100-150 ppm (7-10 degrees Clark) and above
- a number of water treatment devices are available. When specifying or installing
Andrews water heaters in hard water areas we would recommend that a specialist in this
area of operation is consulted.
Contact Andrews Water Heaters for further information.
INSTALLATIONSECTION 3
HYDROJET
SYSTEM
WATER
CONNECTIONS
WATER QUALITY
AND TREATMENT
8
The upper “jet
ports”direct the flow
outward to begin the
dynamic mixing
action.
The lower “jet ports”
direct the flow
inward to increase
the turbulence.
How the
system works
The heater is fitted with
the Hydrojet Total
Performance System
incorporated in the cold
inlet dip tube. The tube is
designed to increase
turbulence and reduce
sediment build up, reduce
thermal stacking and
increase delivery.

The water heater must be supplied from a cold water feed cistern and the hot water
supply pipe must be fitted with an open vent pipe in accordance with BS 5546. Local
regulations and bye-laws must be observed when installing the system but typical water
service layouts are shown in Fig. 3.
The cold water feed cistern must have an actual capacity greater than the hourly
recovery rate of the heater or heaters to which it is fitted, the minimum actual capacity
allowed for a feed cistern is 227 litres (50 gal).
The actual cistern capacity is the capacity to the normal water line of the cistern. All
cisterns used should be to the relevant British Standard and the distance from the normal
water line to the top of the cistern should be as laid down by the water authorities.
The cold water inlet and hot water outlet are identified on top of the heater. Connect the
cold water feed and hot water outlet to these nipples with union adaptors for ease of
servicing.
CAUTION - DO NOT APPLY HEAT TO THESE NIPPLES IF MAKING CAPILLARY
SOLDERED JOINTS AS THEY ARE FITTED WITH PLASTIC INSERTS. MAKE THE
CAPILLARY JOINTS TO THE PIPES BEFORE CONNECTING TO THE HEATER. A DRAIN
COCK IS SUPPLIED WITH THE HEATER AND THIS SHOULD BE FITTED TO THE
APPROPRIATE BOSS AS SHOWN ON THE DRAWING.
After installation of the water system open the main water supply valve, flush the system
and fill the heater. Open the hot taps to allow air to escape from the system. When the
system is free of air, close the taps and check for leaks at the control thermostat, drain
cock and pipe connections at the top of the heater.
INSTALLATION SECTION 3
WATER
CONNECTIONS
VENTED SYSTEMS
9
Fig.3
Typical Installation -
Vented System
Open Vent
Overflow
Hot Water
Service Pipe
Cold Water
Inlet Valve
Flue
Union
Adaptor
Gas Control Thermostat
Check Valve
Secondary Return
Stop Valve
Cold Water Feed
Cold Water Cistern

INSTALLATIONSECTION 3
When used in an unvented system, the Andrews storage water heater will supply hot
water at a pressure of 3.5 bar (50.8 psi) providing this pressure is available at the mains
feed. During conditions of no flow, whilst the burner is operating, the pressure of the
system will rise to a maximum of 6 bar (87.0 psi).
When testing the system it is recommended that a maximum test pressure of 8.62 bar
(125 psi) be employed.
The Andrews range of storage water heaters can be used on unvented hot storage water
systems with the addition, to the standard heater, of an "Unvented Systems Kit" Part No.
B213 obtainable from Andrews Water Heaters.
All fittings and materials must be suitable for use with drinking water and listed in the
current Water Research Centre "Materials and Fittings Directory".
Installation of unvented hot storage water systems must comply with the requirement
G3 of the Building Regulations.
Fig.4 p11 lists and illustrates the component parts of the Unvented Systems Kit.
Fig.5 p12 illustrates the general arrangement of the components. The Wall Mounting Kit
is available as an optional extra.
Item F4 must be fitted into the Temperature Relief port (see Fig. 6, p13)
When assembling items F1 and F2 care must be taken to ensure that the flow arrows
marked on the components are pointing in the direction of flow i.e. towards the water
heater.
The cold water for services may be drawn from the 22mm compression port on item
F1(a). The water pressure at this point will be similar to that available at the hot water
outlet of the water heater. If port (a) is not used it should be sealed with the blanking
plug supplied.
If higher flow rates are required for the cold water services a suitable "tee" fitting should
be included in the pipework upstream of item F1.
The discharge pipe from the tundish should be of suitable metal and be at least one pipe
size larger than the outlet pipe on the safety devices.
(See Building Regulations Approved Document G3).
WATER
CONNECTIONS
UNVENTED
SYSTEMS
10

1
1
1
1
1
1
1
1
1
Pressure Reducing Valve
Expansion Valve / Check Valve
Expansion Vessel
Temperature / Pressure Relief Valve
3⁄4”x1⁄2”Reducing Bush (Not shown)
Tundish
Expansion Vessel Wall Mounting Kit (Optional)
Comprises
Hose Assembly
Wall Bracket Assembly
C780
C781
E319
E320
E321
E322
B229
C788
E323
F1
F2
F3
F4
F5
F6
F7
F8
INSTALLATION SECTION 3
11
Fig. 4
Unvented
Systems Kit
Ref Part No. Description Qty
B213 Complete Unvented System Kit
Comprises
1
F3
F4
F2
F1 (a)
F6
F7
F8

Fig.5
Unvented Systems Kit,
Correct Sequence
INSTALLATIONSECTION 3
WATER
CONNECTIONS
12
F3
Expansion Vessel
F4
Temperature/
Pressure Relief
Valve
Cold Water Inlet
to Water Heater
F2
Check Valve/
Expansion
Valve
F6
Tundish
F1
Pressure
Reducing
Valve/
Strainer
Cold Water Feed
Balanced Cold
Water Take-off
(if required)
NB. Tees, elbows, stop valve and pipework not supplied.
F7
Hose Assembly
F8
Wall Bracket Assembly
F5
Reducing Bush

INSTALLATION SECTION 3
WATER
CONNECTIONS
GAS
CONNECTIONS
Fig. 6
Typical Installation,
Unvented System
13
Hot water service
Cold Water Take Off
Cold Water Inlet
To drain
F3
F1
F2
F4
F5
F6
Check Valve
Secondary Return
THE APPLIANCE MUST ONLY BE USED WITH NATURAL GAS.
The installation of the gas supply should conform to the requirements of IM/16 published
by British Gas p.l.c. or BS 6891. Jointing compound used must conform to BS 6956 Pt 5.
CAUTION - DO NOT APPLY HEAT IN CLOSE PROXIMITY TO THE GAS CONTROL
THERMOSTAT AS THIS WILL RESULT IN DAMAGE OCCURRING TO THE CONTROL.
Fit a 1/2, gas supply cock immediately upstream of the gas control thermostat and
connect to the gas supply. Pressure test the gas installation for soundness. If any doubt
exists as to size of gas supply pipe, consult your local Gas Region.
It is recommended that a pressure test point is fitted on the input next to the gas supply
valve.

COMMISSIONINGSECTION 4
GAS
CONNECTIONS
TO LIGHT
THE BURNER
TO SHUT OFF
THE BURNER
TO CHECK
MAIN BURNER
PRESSURE
14
CAUTION: DO NOT OPERATE THE WATER HEATER UNTIL THE STORAGE VESSEL IS
COMPLETELY FILLED WITH WATER, WITH WATER RUNNING FROM ALL HOT TAPS.
Open the main gas supply cock after all connections to the gas control thermostat are
complete, and test all connections with soap solution.
1. Remove outer cover wait 3 minutes for any unburnt gas to vent.
2. Turn the gas control knob to pilot. (see below)
3. Fully depress the gas control knob and the piezo ingnitor. With the pilot burner alight,
hold the gas control knob for 20 seconds. When the gas control knob is released the
pilot should remain lit, if not repeat the operation. The pilot can be seen through the
sight glass on the inner cover.
4. Replace outer cover.
5. Set the temperature indication dial to the required temperature. (see below)
6. Turn the gas control knob to ON, the burner should now light, if not repeat the
operation. (see below)
For long periods only, eg. holidays or periods of 7 days or more, turn the gas control
knob to ‘PILOT’position, depress slightly and turn clockwise to ‘OFF’. Turn off the gas
service cock.
For shorter periods, eg. less than 7 days, leave the heater under the control of the
thermostat.
N.B. If the pilot should become extinguished for any reason, turn off the appliance, and
wait three minutes before attempting to relight.
1. Turn burner OFF as above.
2. Remove brass cap from burner adjustment port. (see below).
3. Release bleed screw A one turn and connect pressure gauge tube.
4. Light burner according to the preceding instructions.
5. Adjust burner pressure at screw B in accordance with data plate.
Turn screw clockwise to increase pressure and anticlockwise to decrease pressure.
6. Turn burner OFF. Remove pressure gauge tube and tighten screw A.
7. Replace brass cap in burner pressure adjustment port. (see below).
Thermostat
Setting
104°F40°C 125°F52°C 143°F62°C 159°F71°C
Approx. Water
Temperature
Correct size and shape
of the pilot flame
OFF :
PILOT :
ON :
Fig.7
Lighting Instructions
Note European Symbols:
30 mm
0123
Fig. 8
Burner Pressure
Adjustment
BA

15
OPERATION SECTION 5
When properly installed and adjusted the Heater will require the minimum of attention.
Should it become necessary to completely drain the heater, close the cold water inlet
valve, open a hot water tap to allow air to enter the system. Fit a suitable hose to the
drain cock and open.
Whenever the Heater is filled with cold water, condensation will form on the cold storage
vessel surfaces when the burner is lit. Condensation is normal and does not indicate a
leak. It will disappear when the storage vessel becomes heated.
The gas control fitted to this heater has a built in limit thermostat (ECO). In case of high
water temperature the gas supply will be automatically shut off. The reason for such a
high temperature must be investigated and corrected before the heater is relit.
The gas control is fitted with a recycling type ECO, this means that once the water
temperature has cooled sufficiently the ECO circuit will close and allow the heater to be
relit. If the gas control has to be changed it must be replaced with an identical model
having the same code number.
If in doubt contact Andrews Water Heaters.

SERVICINGSECTION 6
BURNER
ASSEMBLY
GAS
CONTROL
VALVE
16
Whilst giving the following instructions for the care of the Andrews Water Heater, we
would recommend that an arrangement is made with your local gas region or installer to
carry out periodic checks of the appliance to ensure trouble free operation and continued
satisfaction.
The burner assembly should be cleaned and checked annually as follows:-
1. Depress slightly the gas control knob and turn to "OFF". Remove the outer burner
cover and the inner door. Remove the IO fixing screws to remove the inner cover.
2. Disconnect from the bottom of the control valve the ‘pilot tube, thermocouple and
main burner supply tube. Withdraw the burner assembly from the heater.
3. Remove the screw securing the pilot assembly to the main burner.
4. Remove the gland nut connecting the pilot tube to the pilot assembly. Withdraw the
pilot tube and remove the pilot restrictor from the end. Clean the pilot restrictor with
acetone and blow through the pilot burner with compressed air.
5. Remove the two screws securing the main burner supply tube to the bottom of the
burner to gain access to the main jet. Remove the main jet and clean with acetone.
Blow through the main burner with compressed air.
DO NOT ATTEMPT TO CLEAN ORIFICES WITH SHARP METALLIC OBJECTS, IF
NECESSARY, USE A WOOD SPLINTER TO CLEAR.
6. Re-assemble in the reverse order of steps 2 to 5 but note:
i) Be sure to engage the rear section of the main burner supply pipe in its location
bracket on the base pan of the heater.
ii) DO NOT OVERTIGHTEN THE THERMOCOUPLE CONNECTION, SCREW IN
FINGER TIGHT AND TIGHTEN A FURTHER 1/4 TURN USING A SPANNER.
7. Turn the control knob to "PILOT" and depress. Using a leak detection fluid check the
joints at both ends of the pilot supply tube. Seal if necessary.
8. Allow 3 minutes for any unburnt gas to disperse and light the pilot flame, check that
the flame is correct, see Fig. 7 and turn the control knob to ‘ON’, the main burner will
light.
9. Check the main burner tube connection at the control valve with leak fluid and seal if
necessary. Replace the outer cover.
This should be checked and serviced by an engineer fully conversant with every aspect of
this piece of equipment.
To remove gas control, first
drain appliance, disconnect
gas pipe union and turn
control anti clockwise, taking
care not to damage threads,
knobs or the valve itself.
Fig. 9
Replacement of
Gas Control