Raypak 131 Operating instructions

This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
SERVICE INSTRUCTIONS
Raypak 131 Pool Heater
TM020
Revision: A
Published: April 09
Spartan
P0131

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
2
Contents
Introduction..........................................................................................................................3
Safety Warning....................................................................................................................3
Pool Heater Model Identification..........................................................................................3
Specifications.......................................................................................................................4
Preventative Maintenance ...................................................................................................5
Water Treatment (Pool Balance) .........................................................................................5
Product Changes.................................................................................................................6
Plumbing & Installation Diagram..........................................................................................7
Lighting Instructions.............................................................................................................8
Wiring Diagrams..................................................................................................................9
131 Wiring Diagram –Grey Control Board........................................................................9
131 Wiring Diagram –Black Control Board (prior to 14/4/09) .........................................10
131 Wiring Diagram –Black Control Board (14/4/09 onwards).......................................11
Sequence of Operation......................................................................................................12
Components and Their Function........................................................................................16
Fault Indication ..................................................................................................................18
Fault Finding......................................................................................................................19
General Fault Finding Chart............................................................................................20
Fault Finding Chart 1.......................................................................................................21
Fault Finding Chart 1.1....................................................................................................22
Fault Finding Chart 1.2....................................................................................................22
Fault Finding Chart 1.3....................................................................................................23
Fault Finding Chart 1.4....................................................................................................24
Fault Finding Chart 1.5....................................................................................................25
Fault Finding Chart 1.6 & 1.7 ..........................................................................................26
Fault Finding Chart 1.8....................................................................................................27
Fault Finding Chart 2.......................................................................................................28
Fault Finding Chart 3.......................................................................................................29
Fault Finding Chart 4.......................................................................................................30
Fault Finding Chart 5.......................................................................................................31
Fault Finding Chart 6.......................................................................................................32
Fault Finding Chart 7.......................................................................................................32
Fault Finding Chart 8.......................................................................................................33
Fault Finding Chart 9.......................................................................................................34
Test Procedures..............................................................................................................34
Component Adjustment Procedures..................................................................................41
Component Replacement Procedures...............................................................................43
Exploded View...................................................................................................................57
Replacement Parts List...................................................................................................58
Gas Type Conversion Procedure.......................................................................................59
Raypak Pool and Spa Heater Warranty (Australia Only) ...................................................60
Document Revision History................................................................................................61

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
3
Introduction
The information provided in these service instructions is based on the pool or spa heater
being installed in accordance with AS 5601 and the Installation Instructions provided with
each pool or spa heater.
Should you require further technical advice on a Raypak Pool or Spa Heater, contact your
nearest Rheem Service Department where genuine replacement parts are also available.
Safety Warning
The purpose of this service manual is to provide sufficient information to allow a person
with the skills as required by the Regulatory Authorities to carry out effective repairs to a
Raypak Pool Heater in the minimum of time.
Safety precautions or areas where extra care should be observed when conducting tests
outlined in this service manual are indicated by print in bold italics and/or a warning
symbol (see below). Take care to observe the recommended procedure.
“Live” testing to be conducted. Personal Protective Clothing (PPE) shall
be worn and an RCD shall be installed between the power point and 3-pin
cord of the pool heater to reduce the risk of electric shock.
Isolate power before conducting the indicated test
Hot surface or liquid. Personal Protective Clothing (PPE) shall be worn to
reduce the risk of scalding.
General warning symbol. Observe the instructions accompanying the
symbol.
If the supply cord is damaged, it must be replaced by the manufacturer or
its service agent or a similarly qualified person in order to avoid a hazard.
When conducting repairs to a gas appliance the gas train including
injector sizes must not be altered or modified in any way.
Pool Heater Model Identification
All identification numbers are designed to convey detailed information about the pool
heater to which it is attached.
P
013
1
N
C
O
P –Domestic Pool/Spa Heater
Approx. thermal input x 10
Series
N –Natural Gas
P –Propane Gas
C –Copper Heat Exchanger
O –On/Off Operation
Note: Model number, serial number and date of manufacture must be quoted in all correspondence.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
4
Specifications
P0131NCO
P0131PCO
Injector size (mm)
1.36
0.77
Burner Pressure (kPa)
0.85
2.64
Minimum Gas Pressure (kPa)
1.13
2.75
Maximum Gas Pressure (kPa)
3.5
Input (MJ)
120
Number of burners
15
Gas inlet connection
RP¾/20
Header connection
40mm
Gas valve
Pre 2007
White Rogers 36E06-301
Post 2007
White Rogers 36G22-216
Ignition module
RAM-H4M7-01
Control board
Millennium grey or black board (24VAC 50Hz)
45ºC inlet high limit
Campini TY60, opens 45ºC closes 35ºC (+/- 3ºC)
55ºC outlet high limit
36TXVG11, opens 55 ºC closes 45 (+/- 3ºC)
Transformer
Primary winding 240 Volts AC 50Hz 62.2 ohms
Secondary winding 24 Volts AC 50Hz 1.3 ohms
Pressure switch¹
Barksdale MSPS-EE05-Q71 or Tecmark MSPS-EE05
Adjustable: 3.5 –34.5kPa, max pressure 55kPa
Flow switch¹
Adjustable: max pressure 1000kPa
40ºC temperature probe
Refer to table on page 40
Control circuit fuse
3A
Relay 1²
Omron LY2N, DPDT, 24VAC, coil resist 186 ohms
Relay 2²
Omron LY2N, DPDT, 24VAC, coil resist 186 ohms
Reset illuminated push button
24VAC LED, 1 X N/O momentary contact
Flow Rate (l/s)
Minimum
1.3
Maximum
6.9
Power Supply
240VAC 50Hertz
¹ The installation will have either a pressure switch or a flow switch depending upon the application (refer to
'Water Pressure Switch‟ on page 17 for more information).
² Models manufactured from the 14/4/09 feature an integrated PCB with power outage auto reset
incorporating the relays.
Auxiliary Component Specifications
Component
Electrical Interface Board (E.I.B)
Millennium 56659201 240VAC (30A max @ 240V)
Note: Auxiliary components are optional and may not be installed.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
5
Preventative Maintenance
It is suggested for peak performance that the pool/spa heater be serviced annually.
1. Clean the cabinet louvres of any dust, lint and debris.
2. Ensure plants or shrubs etc are not obstructing the cabinet louvres.
3. Check for signs of leaking at pipe fittings and headers.
4. Clean the burner bars.
5. Check for signs of sooting, the presence of soot accumulation indicates an abnormal
operating condition.
6. Check the main burner pressure and compare to that indicated on the rating label,
adjust if required. Remember to replace the pressure test point screw.
7. Check main burner flame to ensure all parts ignite readily and that the flame is blue
with little or no yellowing of the tips.
8. Check operation of the flame failure sensor. The burner should extinguish immediately
the flame sensor is disconnected.
9. Check for signs of excessive corrosion on the cabinet and inside the combustion
chamber.
10.With the burner operating disconnect one wire from the 45°C high limit (located on the
inlet header), the burner should extinguish. Reconnect the wire; the reset button lamp
should illuminate however the burner must not light. Press the reset button, the lamp
should extinguish and the burner should light.
11.With the burner operating disconnect one wire from the 55°C high limit (located on the
outlet header), the burner should extinguish. Reconnect the wire; the reset button lamp
should NOT illuminate and the burner should reignite.
12.Warn customer of the danger of storing pool chemicals and/or using flammable
materials or aerosol spray packs near the pool/spa heater. Aerosols and harsh
chemicals can cause premature failure of pool/spa heater components.
Water Treatment (Pool Balance)
Maintenance level
Fibreglass Pools
Fibreglass Spas
Other Pool/Spa types
Water temp (ºC)
20 –31
32 –40
20 –40
PH
7.3 –7.4
7.3 –7.4
7.6 –7.8
Total Alkalinity (ppm)
120 –150
120 –150
150 –200
Calcium Hardness (ppm)
200 –300
150 –200
80 –100
Salt (ppm)
6000 MAXIMUM
Free Chlorine (ppm)*
2 –3
2 –3
2 –3
* Free Chlorine must not exceed 5ppm, however occasional chemical shock dosing of the
pool or spa water should not damage the heater providing that the water is balanced to the
above conditions.
Automatic chemical dosing devices and salt chlorinators are usually more efficient in
heated water. Unless controlled, they can lead to excessive chlorine levels that can
damage the pool/spa heater.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
6
Product Changes
Gas Valve Change
131 Model pool heaters manufactured before the 27/3/07 utilise a White Rogers 36E06-
301 gas valve, models manufactured after the 27/3/07 utilise a White Rogers 36G22-216
gas valve. The 36E06-301 gas valve is no longer available however the 36G22-216 gas
valve is a direct replacement. For more information refer to „Gas Valve‟ on page 52.
Change to Black Control Board
Raypak pool and spa heaters manufactured from July 2005 to the 31/10/2006 were fitted
with a controller which has a grey decal on the control panel. Models manufactured from
November 2006 onwards are fitted with a revised control board which incorporates
additional software functions, fault codes and a revised wiring arrangement. The revised
control board can be identified by a control panel with a black decal.
This Service Manual including fault finding charts covers both types of control panels.
Both control boards operate and are programmed in a similar fashion however black
control boards have additional fault codes and features. It should be noted that the wiring
arrangement also differs depending upon whether a black or grey board is fitted. Refer to
page 9 for grey board wiring diagram and pages 10 & 11 for black board wiring diagrams.
Black control board
Grey control board
Addition of Reset Button Safety Lock Out Circuit & Weather Shielding.
All Raypak pool and spa heaters manufactured after 14/04/2008 have been fitted with an
additional safety feature and weather shielding. The additional safety feature incorporates
a red reset button located on the front control panel and two relays located in the control
box (relay 1 and relay 2).
The safety lock out circuit prevents the heater from operating if the 45ºC inlet high limit
trips (open circuits) due to an over temperature condition.
If the 45ºC inlet high limit trips (open circuits), relays 1 and 2 open and „lock out‟ the pool
heater control circuit preventing operation until the 45ºC inlet high limit closes and the pool
heater is manually reset by pressing and releasing the red reset button. For more
information refer to „Sequence of Operation‟ on page 12 and wiring diagrams on pages 9-
11.
Pool and spa heaters manufactured prior to the 14/04/2008 did not have the safety lock
out circuit or additional weather shielding fitted. A recall campaign to rework all Raypak
pool and spa heaters in the field was commenced in March 2008.
Any Raypak pool or spa heater that does not have a red reset button located
on the control or side panel does not have a safety lock out circuit or
additional weather shielding and MUST be reworked. Contact Rheem Service
for more information.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
7
Addition of Auto Reset PCB (Incorporating Safety Lock out circuit)
All Raypak pool and spa heaters manufactured from the 14/4/09
have an additional auto reset PCB fitted. This control automatically
resets the safety lockout circuit when power is applied for the first
time or from a power outage overcoming nuisance lock outs.
The auto reset PCB also incorporates the safety circuit functionality
noted above including relays (relay 1 and relay 2).
A manual reset (by pressing the red reset button) is still required should the 45°C inlet over
temperature cut out open circuit.
Plumbing & Installation Diagram

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
8
Lighting Instructions
Main Burner
1. STOP read all of the safety information in the installation and operating instructions.
2. Press the pool heater Power button until the display is off.
3. Turn OFF all electrical power to the pool heater.
4. The pool/spa heater is equipped with an automatic ignition system, which lights the
burner.
5. Wait five (5) minutes to clear out any unburnt gas. STOP if you smell gas and follow
the safety instructions in the installation and operating instructions. If you do not smell
any gas go to the next step.
6. Turn the gas isolation valve to the ON position.
7. Turn on electrical power to the pool/spa heater.
8. Press and release the red reset button, the reset light should go out. NOTE: For
models manufactured from 14/04/09 onwards the reset button should NOT illuminate
and does not need to be pressed.
9. Press and release the Power button on the control panel and set the thermostat to the
desired setting.
10. The burner should light.
If the pool heater is not equipped with a red reset button, contact Rheem
Service.
To turn off the pool heater
1. Press the Power button on the control panel and wait for the display to extinguish
(„OFF‟position).

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
9
Wiring Diagrams
131 Wiring Diagram –Grey Control Board

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
10
131 Wiring Diagram –Black Control Board (prior to 14/4/09)

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
11
131 Wiring Diagram –Black Control Board (14/4/09 onwards)

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
12
Sequence of Operation
1. MODELS MANUFACTURED PRIOR TO 14/4/09: When power is supplied to the
heater for the first time or power is removed and restored, the red reset button will
illuminate indicating that the heater requires resetting. The red reset button is required
to be pushed and released to reset the heater which will then be ready for operation.
Actuation of the red reset button energises relay 1 which causes the reset indicator
lamp to extinguish. Sequence of operation beyond this point assumes that the heater
has been successfully reset.
2. Manual operation of the controller power button turns the controller on to the last mode
of operation. Actuation of the pool/spa pump causes water to flow through the heater.
The resulting water pressure causes the pressure switch contacts to close enabling
operation of the control board gas valve output which at this stage is de-energised.
3. If the water temperature detected by the water temperature probe is 1ºC or less than
the control board set point temperature, the control board will initiate a call for heat and
supply power to relay 2 which will energise and supply power to the RAM ignition
module via the normally open contacts of relay 2 (which closed when the control board
called for heat), relay 1 (which closed in step 1 when the reset button was operated),
and the normally closed contacts of the 55ºC outlet high limit (for grey boards also via
the water pressure switch contacts).
4. When power is supplied to the RAM ignition module, the ignition module will perform
an internal check to ensure that it is functioning correctly. If the internal check fails the
ignition module will „lock out‟and require resetting by turning the controller off for 5
seconds and then turning the controller back on again. If the ignition module is reset in
this manner operation will recommence from step 4.
5. If the ignition module internal check is successful, the ignition module will check the
flame sensor to ensure a flame is not present. If a flame is present a DC current (µA)
will be generated by the flame sensor and will be detected by the ignition module
which will „lock out‟and require resetting by turning the controller off for 5 seconds and
then turning the controller back on again. If the ignition module is reset in this manner
operation will recommence from step 4.
6. If a flame is not detected in step 5, the ignition module will energise the igniter (which
will glow red hot) and then perform a second flame sensor check to ensure a flame is
not present. If a flame is present a DC current (µA) will be generated by the flame
sensor and will be detected by the ignition module which will „lock out‟and require
resetting by turning the controller off for 5 seconds and then turning the controller back
on again. If the ignition module is reset in this manner operation will recommence from
step 4.
7. If a flame is not detected in step 6, and when the ignition module detects an igniter
current draw of > 1.4 amps, the ignition module will energise the gas valve which will
open supplying gas to the burner which is ignited by the hot surface igniter. This type
of ignition is termed HSI (hot surface ignition).

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
13
8. Upon successful ignition of the burner, the resulting flame impinges on the flame
sensor which generates a DC micro amp (µA) current which is detected by the ignition
module. If a flame is not detected within 15 seconds from igniter power up, the ignition
module will de-energise the gas valve, „lock out‟ and require resetting by turning the
controller off for 5 seconds and then turning the controller back on again. If the ignition
module is reset in this manner operation will recommence from step 4.
9. If a flame was detected in step 8, the burner is now operating and will remain lit until
one of the following occurs at which time the gas valve will be de-energised (close):
I. The call for heat ends (water temperature detected by the water temperature
probe is 0.5ºC above the control board set point temperature).
II. The pressure switch contacts open (no water flow).
III. The 45ºC inlet high limit switch contacts open (over temperature condition). Refer
to notes b, c and d below.
IV. The 55ºC outlet high limit switch contacts open (over temperature condition).
V. An external switch or time clock contact opens (if fitted).
VI. Flame failure occurs (ignition module flame sensor does not detect a DC current).
VII. The control board is turned off.
Notes:
a) If the 45ºC inlet high limit contacts are open at the start of a call for heat (step 3),
relay 1 will be de-energised and no further operation will take place until the 45ºC
inlet high limit contacts close (cool below 35ºC) at which time the reset indicator
lamp will illuminate. The heater will then require resetting by pressing the red reset
button. Also refer to point d below.
b) If the 45ºC inlet high limit contacts open during a call for heat and whilst the burner
is operating (step 9),, relay 1 and the gas valve will be de-energised and no further
operation will take place until the 45ºC inlet high limit contacts close (cool below
35ºC) at which time the reset indicator lamp will illuminate. The heater will then
require resetting by pressing the red reset button. Also refer to point d below.
c) If a call for heat is not in progress and the 45ºC inlet high limit contacts are open,
operation of the reset button will reset the heater, however, if the 45 ºC inlet high
limit contacts are still open when a call for heat is initiated no further operation will
take place until the 45ºC inlet high limit contacts close (cool below 35ºC) at which
time the reset indicator lamp will illuminate. The heater will then require resetting as
in step 1.
d) NOTE: The reset button cannot reset the heater whilst a call for heat is in progress
and the 45°C Hi Limit contacts are open.
Pump Operation
Pump operation is not controlled by the heater however the pump must be operating for
the burner to ignite. Actuation of the pool/spa pump causes water to flow through the
heater and the resulting water pressure causes the pressure switch contacts to close
enabling operation of the burner control circuit.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
14
Operational Flow Chart 1
Reset button
pushed &
released?
YES
Water temp < set
temp - 1ºC? YES
YES
External switch or
time switch
closed? (if fitted)
NO
YES
NO
Water pressure
switch closed?
55º high limit
contacts closed?
YES
NO
2
3
5
HEATER OPERATION
Control board set
to „Manual‟?
Is time within auto
set time period?
NO
YES
YES NO
Power supplied to
heater
Control board
turned on?
NO
45º high limit
contacts closed?
NO
YES
YES
C
YES
(1) Control board is turned on by pressing
& releasing the „power‟ button.
Heater fitted with
auto reset PCB?
Auto reset safety
circuit board resets
D
Reset button
pushed &
released?
YES
NO
NO
(1)
YES
E.I.B. OPERATION
Control board set
to „Manual‟?
Start
NO Is time within auto set time
period?
NO
Aux 2
enabled? Aux 3 enabled? Aux 4 enabled? Aux 5 enabled? Aux 6 enabled?
YES
YES
A B
YES NO
A B
YES NO
A B
YES NO
A B
YES NO
A B
YES NO
A B
YES NO
A B
Dotted line denotes optional
electronic interface box (E.I.B.)
Disabled Aux relay(s)
de- energised
Enabled Aux relay(s)
energised
Control board set to
„AUTO‟
4
C
Relay 1 de-energised
Reset lamp
illuminates
45º high limit
contacts close
when temp < 35º
Gas valve de-energised
if on (pilot & main valve
close)
Heater Fitted with
auto reset PCB?
Auto reset safety circuit
board open circuits gas
valve circuit
YES
NO Heater fitted
with auto
reset PCB?
D
NO YES
NO
NO
Reset lamp
illuminates
Relay 1 energised
Reset lamp
extinguished
Relay 2 energised
Control board initiates
call for heat
Control board set to
„AUTO‟
Aux 1
enabled?

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
15
Operational Flow Chart 2
Flame signal
lost? (< 0.2µA) YES
Water temp = Set
temp + 0.5ºC?
NO
Ignition
& flame
proving
(15 sec
max)
Burner
operation
45º high limit
contacts open?
NO
External switch or
time switch
contacts open? NO Water pressure
switch contacts
open?
55º high limit
contacts
open?
2
NO NO
3
YES
4
YES
5
YES YES
NO
YES
YES
Flame signal >
0.2µA detected?
Internal check
ok?
NO
NO
NO
YES
System
check
(3 sec)
Approx
5 sec Flame signal >
0.2µA detected?
NO
Flame signal >
0.2µA detected?
YES
D
D
Ignitor current
draw > 1.4A?
YES
YES
Has 15 sec‟s
expired since
igniter on?
NO
YES
E
E
NO
Igniter on
Gas valve energised
Gas valve opens
Igniter off
Igniter off
Relay 1 de-energised Gas valve
de-energised
Gas valve
de-energised
Gas valve closes
Gas valve closes
Ignition module
de-energised
Ignition module
de-energised
Gas valve
de-energised
Ignition module
de-energised
Control board ends
call for heat
Ignition module 3
flash indication
Ignition module
3 flash indication
Ignition module
4 flash indication
Ignition module
energised
LOCKOUT
Gas valve closes
Gas valve de-
energised
Turn controller on
Turn controller off
Igniter off
False Flame
Flame Failure
Relay 2
de-energised
Gas valve closes
5 sec
delay

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
16
Components and Their Function
Gas Valve - An electromagnetic valve designed to control gas
flow to the burner. 131 models manufactured before 27/3/07
utilise a White Rogers 36E06-301 gas valve, models
manufactured after the 27/3/07 utilise a White Rogers 36G22-216
gas valve.
36E06-301 and 36G22-216 gas valves are equipped with a
redundant and main solenoid valve, a pressure regulator, the
36G22-216 is also fitted with an on/off switch. Both gas valves
are available in Natural Gas only and can be converted to LP
Gas; refer to page 59 for gas type conversion procedure. Note:
36E06-301 gas valves are no longer available however the
36G22-216 gas valve is a direct replacement.
The gas valve gas type can be determined by the colour of the regulator spring (bare
metal coloured spring for NG and grey/white powder coated spring for Propane).
The inlet gas pressure range is 1.1 –3.5 kPa for Natural Gas and 2.75 –3.5 kPa for
Propane Gas.
Hot Surface Igniter - When energised, the hot surface igniter glows red hot and ignites
gas flowing from the burner.
Flame Sensor - A probe utilised to detect if a flame is present. The probe projects across
the flame area of the burner and when in contact with the flame produces a DC current
(µA) which is detected by the ignition module.
Burner Manifold - A pipe fitted with a series of injectors which deliver gas from the gas
valve to the burner.
Burner - A series of bars connected to the burner manifold and held in place by a sheet
metal surround. Each bar contains a series of holes from which air/gas mixture flows. The
burner is ignited by the hot surface igniter.
Injector - A jet with an orifice used to deliver gas for combustion. The burner injectors are
located on the burner manifold. Injectors have a specific orifice size which is determined
by required thermal input, burner pressure and gas type.
Transformer - An electromagnetic device that transforms the incoming power supply from
240 volts AC to 24 volts AC. The secondary voltage (24 volts AC) is utilised for operation
of the control circuit components and gas valve.
45ºC Inlet High Limit - A normally closed temperature sensitive switch mounted on the
inlet header connection which will cut power to the gas valve if an over temperature
condition occurs. If the inlet water temperature reaches 45ºC or more, the 45ºC inlet high
limit contacts will open circuit shutting down the gas valve and burner and illuminating the
red reset button. The 45ºC inlet high limit contacts will automatically close when the
detected water temperature drops to 35ºC however heater operation cannot continue until
the heater is manually reset. Refer to sequence of operation on page 12 for more
information.
36G22-216

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
17
55ºC Outlet High Limit - A normally closed temperature sensitive switch mounted on the
outlet header connection which will open circuit power to the gas valve if an over
temperature condition occurs. If the outlet water temperature reaches 55ºC or more, the
55ºC outlet high limit contacts will open circuit shutting down the gas valve and burner.
The 55ºC outlet high limit contacts will automatically close when the detected water
temperature drops below 45ºC at which time heater operation will automatically continue.
Water Pressure Switch - A normally open adjustable pressure sensitive switch utilised to
detect the presence of water flow (pressure) in installations where the inlet/outlet pipe work
is less than 1500 mm above or below the water level of the pool. For installations which
exceed this range an external flow switch must be installed (refer to „Water Flow Switch‟
on page 17 for more information).If the correct water flow (pressure) is present, the
pressure switch contacts will close enabling operation of the gas valve/ignition system
(refer to page 42 for pressure switch adjustment procedure).
Water Flow Switch - A normally open adjustable flow sensitive switch utilised to detect
the presence of water flow in installations where the Inlet/Outlet pipe work is greater than
1500 mm above or below the water level of the pool. For installations where the
Inlet/Outlet pipe work is less than 1500 mm above or below the water level of the pool a
pressure switch must be installed (refer to „Water Pressure Switch‟ on page 17 for more
information). If correct water flow is present the flow switch contacts will close enabling
operation of the gas valve/ignition system (refer to page 42 for flow switch adjustment
procedure).
Water Temperature Probe - A thermistor located on the inlet header manifold which is
utilised to detect the water temperature entering the heater (pool/spa water temperature).
The temperature probes resistance value will change according to the detected
temperature. The control board detects the changing resistance value and utilises this
input to display the water temperature and to determine if a call for heat is required. Refer
to page 40 for water temperature probe test procedure and temperature/resistance chart.
Solar Collector Water Temperature Probe (optional) - A thermistor located on the solar
collector (if fitted) which is utilised to detect the water temperature at the solar collector(s).
The solar collector temperature probes resistance value will change according to the
detected temperature.
The control board will monitor the water temperature at the solar collector and if the water
temperature at the solar collector (as detected by a solar collector water temperature
probe) is above the inlet water temperature (as detected by the pool heaters water
temperature probe), the control board will activate a solar diverter valve (if fitted) that
allows the water from the solar collector to be used as inlet water to the pool heater. Refer
to page 40 for water temperature probe test procedure and temperature/resistance chart.
Control Board (Controller) - An electronic PCB which monitors the inlet water
temperature and controls the water temperature by energising and de-energising the
ignition module. The control board has an LCD display with push buttons which allows for
user interface. The control board can also communicate via an electric interface board
(EIB) to provide additional switching of remote components i.e. pool lighting, garden
lighting and/or water fountains.
A remote controller is also available as an option.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
18
Fault Indication
The control board constantly monitors the status of the water temperature probe and solar
temperature probe if fitted (black boards only). If a malfunction has been detected, the
control board will display the following error codes to indicate the fault condition:
Fault
Black Board
Grey Board
Heater rework required *
F1
N/A
Water temperature probe open circuit
F2
OC
Water temperature probe short circuit
F3
SC
Solar thermistor probe short circuit
F4
SS
Water pressure switch contacts open
o
N/A
No mains power
PO
N/A
* F1 fault previously indicated an over temperature condition. This fault condition is no
longer applicable due to wiring changes. If a F1 fault occurs contact Rheem Service.
Water Pressure Switch Indication (black boards only): If the
water pressure is low or there is no flow through the heater, the
water pressure switch contacts will open. If an open circuit
pressure switch condition is detected power will be removed from
the gas valve and the pilot and burner will shut down (if on).
If the controller is set to „On‟ or „AUTO‟ and the water pressure switch contacts are open, a
small „o‟ will be shown to the left of the temperature display.
No Mains Power Indication & Power Backup (black boards only): The controller (and
remote controller if fitted) has a super capacitor power backup to keep the time of day
clock operating, maintain any programmed time periods and remember the last operating
mode if mains power is lost (or power supply to control board is lost).
Whenever mains power (or control board power) is lost, the
controller will disable all control relays and backlight and enter a
power saving mode which will maintain the time of day and any
programmed time periods for between 1.5 to 2 hours. During a
period of „no power‟ the LCD will display „PO‟.
If power is restored before the expiration of the power backup time, the controller will
resume its last operating mode.
Pool/Spa Heater Run Time: The controller records and stores the
number of hours the heater has been operating up to a total of
19990 hours. Run time information can be displayed on the LCD by
pressing and holding down the AUX button for 10 seconds whilst
the controller is in „OFF‟mode.
The displayed hours must be multiplied by 10 to calculate the actual number of hours the
heater has been operating. In the example shown above the heater has been operating for
a period of 88 X 10 = 880 hours (880 –889 hours). Note: If „0‟ is displayed the heater has
been operating for 0 –9 hours.

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
19
Fault Finding
Test Equipment
A list of test equipment which will assist in conducting diagnostic procedures is provided
below. This equipment is available from Rheem Service Spare Parts Department.
Fine probe adapter kit
WH0020082
Probe to alligator clip kit
WH0020084
Fault
Fault finding chart
Page
Heater not operating
1
21
1.1
22
1.2
22
1.3
23
1.4
24
1.5
25
1.6, 1.7
26
1.8
27
Water not hot enough
2
28
Water too hot
3
29
High Limits Tripping
4
30
No or low water flow
5
31
Auxiliary switching not working
6
32
Remote controller not working
7
32
Leaking
8
33
Noisy
9
34

TM018 Raypak 131 Type A Pool & Spa Heaters REV: A
D.O.I: 8/04/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
20
General Fault Finding Chart
1
General Fault Finding
Is the complaint for
water not hot enough?
Is the complaint for
heater not operating?
Is the complaint for
water too hot?
Is the complaint for 45º
and/or 55º high limits
tripping?
NO
NO
NO
YES
2
3
4
8
YES
YES
NO
Is the complaint for
auxiliary switching not
working?
NO
Is the complaint for no
or low water flow?
NO
5
6
YES
YES
Is the complaint for
remote controller not
working?
NO
7
YES
Is the complaint for
leaking?
9
YES
Noisy water heater
Is the 45º and/or 55º
high limit tripping? NO
YES
YES