TM090 12-26 Series II CFGWH Service Instructions
REV AB
– Issued February 2019
This document is stored and maintained electronically by Rheem Technical Support. All printed copies
are deemed “uncontrolled”
26
ERROR CODES
The following table outlines the error codes, possible causes and diagnostic tests to conduct. More
detailed diagnosis is outlined in the fault finding and operational flow charts.
Error
Code
Fault Condition
Items To Check
10
Abnormal low rate combustion
Blockage in the heat exchanger fins, fan, air
intake or flue diagnostic point 4
11
Ignition failure at start up
P.G.F.R Valve - diagnostic point 10
G.I.S Valve - diagnostic point 11
Igniter - diagnostic point 12
Solenoid valve 2- diagnostic points 13,
Flame sensors 1,diagnostic points 14
12
Flame failure during operation
P.G.F.R Valve - diagnostic point 16
G.I.S Valve - diagnostic point 16
Solenoid valves 1, 2 & 3 - diagnostic point 16
Flame sensors 1 & 2.- diagnostic points 16
14
Over heating
Over Heat Limiter - diagnostic point 2
15
Very high temperature
Heat exchanger thermistor - diagnostic point 6
P.G.F.R Valve - diagnostic point 10
24
Operational switch faulty
MAX, MIN or Adj button on PC board.-. Remote
controller & Bath fill switches
31
Inlet thermistor open circuit
Water inlet thermistor - diagnostic point 5
32
Heat exchanger thermistor open circuit
Heat exchanger thermistor - diagnostic point 6
33
Outlet thermistor open circuit
Hot water thermistor - diagnostic point 7
34
Ambient air thermistor open circuit
Ambient air thermistor - diagnostic point 8
35
Thermistor connections crossed
Connection points of thermistors
51
Gas cut off malfunction (SV0 failure)
G.I.S Valve - diagnostic point 16
Flame sensor 1 & 2 - diagnostic point 16
52
P.G.F.R control failure
P.G.F.R Valve
– diagnostic point 16
PC Board (PCB)
61
Abnormal fan speed or fan failure
Fan motor
– diagnostic point 4
PC Board (PCB)
65
Malfunction of water volume control motor Water volume control motor - diagnostic point 15
71
G.I.S valve control failure
O.H.L. - diagnostic point 2
Heat exchange thermistor diagnostic point 6
Gas. Inlet Solenoid Valve diagnostic 10
Solenoid Valves 1, 2 & 3 diagnostic 16
PC Board (PCB)
72
Detected false flame
Flame sensors 1, & 2 - diagnostic point 9
PC Board (PCB)
73
Vent type control data failure
Gas type circuit board
74 75
76
Communication problem between remote
controller and water heater
Remote controller PC Board or
Remote controller cable
79
Fan motor current detection failure
Fan motor
– diagnostic point 4
PC Board (PCB)
80
Gas cut off defective
(Solenoid valve 1-3 failure)
Solenoid valve 1, 2 & 3 - diagnostic point 16
Flame sensor 1, & 2 - diagnostic point 16
81
No false flame detected
Solenoid valve 1, 2 & 3 - diagnostic point 16
Flame sensor 1, & 2 - diagnostic point 16
PC Board (PCB)
82
Functional problem on gas type circuit
board
Gas type circuit board
90
Decrease in fan motor ventilation.
Blockage in the heat exchanger, fins, fan
air intake or flue way
99
Decrease in fan motor ventilation.
(Operation stop)
Blockage in the heat exchanger, fins, fan
air intake or flue way
Note: see page 22 for interpretation of abbreviations.