Rheem TRITON GHE80SS Service Training Manual page 44

Rheem TRITON TM
Service Manual
TROUBLESHOOTING ERROR CODES
Error T020 Lower Tank Sensor Open
Control senses the lower tank temperature sensor open. This will not disable the unit or keep it from heating water. The alert will clear on its
own when the issue is resolved.
• Confirm wiring harness is securely connected to lower tank
temperature sensor and confirm the wiring harness at the
P2 connection on the control board is secure.
• If no wiring is loose, disconnect wiring from lower tempera-
ture probe. Check ohms reading across the pins of the sen-
sor. A good sensor should read between 1K to 36K ohms.
If sensor reads open, replace the sensor.
Error T021 Lower Tank Sensor Shorted
The control board is detecting a short in the lower temperature probe wiring. This will not disable the unit or keep it from heating water.
• Disconnect the wiring from lower temperature probe. If unit
gives an alarm for T020, replace the lower temperature
probe.
• If you do not get the T020, turn the unit off. Disconnect the
lower temperature probe wiring and the P2 harness at the
ignition control board and check for continuity across the
wires at the lower temperature probe. If you have continui-
ty, there is a short in the wiring harness. Replace the wiring
harness.
Error T029 Failed Ignition. Retrying
The unit will fail nine times and give an A029. It will fail 9 more times and give an A029. On the 27
code.
• Refer to Error A001 for troubleshooting. (See Page 33)
Error T032 Lower Tank Temp A/D Error
The control board cannot convert the analog reading from sensor to digital reading to the display. This will not disable the unit or keep it from
heating water.
• Cycle power. If issue remains, replace the ignition control
board.
Error T105 Water Leak Sensor Not Installed
• Check wiring for proper connection from wiring harness to control board, ensuring wir-
ing is not damaged (4 wire, 2 blue/2 black)
• If wiring is properly connected, disconnect from wiring harness and check continuity
across bottom terminals (If leads are too large, use a smaller metal item such as a
paper clip to check for continuity(right)). The top terminals will only have continuity if
the sensor is wet, which will cause an additional error code.
• If there is no continuity (open circuit) replace leak sensor.
44
• If sensor has a reading between 1K to 36K ohms, recon-
necting the wiring to the sensor. Turn off power and discon-
nect P2 harness from ignition control board and check the
ohms reading across the 2 blue wires. Your reading should
be about the same as the reading you got on the sensor. If
not, replace the wiring harness. If readings match and error
won't clear then replace the ignition control board.
• If above checks determined no resolution, replace the igni-
tion control board.
failure, the unit will lock out with an A001
th