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11112014GW
Code 52 Troubleshooting Procedure
Modulating Solenoid Valve Signal Abnormal (POV)
1.
Check wiring harness for loose, broken or damaged connections from POV valve back to PC
board.
2.
Unplug POV valve using a volt/ohm meter and check resistance readings across the POV coil on
the gas valve. The proper resistance reading for this coil can be found in the Tech Data Sheet
found on the back side of the unit’s front panel or in the Rinnai Water Heater Service Manual for
that model unit. If you find the coil to be open replace the gas valve. If resistance reading is
found to be within specification, proceed to item #3 below.
Note: Resistance readings can vary from meter to meter based on the meter’s accuracy range
and battery life. A weak battery can affect readings; replace your battery if in doubt before
performing service. In addition; make sure you have you meter set to the correct resistance
(ohm) setting and the component being checked is isolated from the unit’s circuit and power
supply.
3.
Check voltage to the POV valve while unit is trying to fire. If you have the proper voltage but
keep getting an error code proceed to the next item.
4.
WARNING:
Disconnect power supply to unit before proceeding with this task. If code 52 still
appears after performing the above inspection replace the PC board.