Rheem IKONIC RTGH-SR84i - THERMISTOR, MOTOR, AND VALVE ERRORS

IKONIC Tankless Water Heater Service Manual
46
ERROR A031
EXPLANATION
Inlet Thermistor Malfunction.
Diagnostic Check
Inlet Thermistor.
ERROR CODE DIAGNOSTICS
Turn Power OFF
Clean scale build-up on inlet thermistor,
and operate unit.
If error code "A031" appears:
Replace inlet thermistor
Replace wiring harness for connector "I".
Remove control board bracket to access inlet
thermistor Molex.
Locate & separate WHITE Molex Measure
resistance across black wires on female end
of Molex
Reconnect Molex.
Measure resistance on connect "I" between
#5 wire (Black) and #7 wire (White)
Reinsert connector "I", and operate the unit.
If error code "A031" appears:
REPLACE CONTROL BOARD.
The resistance is
7K - 23K Ω?
The resistance is
7K - 23K Ω?
No
No
Yes
Yes