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11112014GW
Code 72 Troubleshooting Procedure
Flame Sensing Device Fault
WARNING:
Turn off the electrical, gas and water supply to the water heater before proceeding.
1.
Check wiring harnesses to flame rods for broken or damaged connections from flame rod back
to PC board.
2.
Ensure flame rod is touching flame when unit fires.
3.
Remove flame rod and check for carbon build-up. Clean flame rod as necessary.
4.
Check inside burner for debris build up that may be shorting out flame rod. If debris on the
burner is touching flame rod this could cause a short circuit and throw a code 72.
5.
Measure micro amp output from flame rod, should maintain a minimum of 1 micro amp.
6.
Replace flame rod, flame rod gasket and PC board.