Rinnai HE Series How To Use Manual page 179

1. Check burner overheat bi‐metal switch wiring harness for loose, broken or damaged
connections from sensor back to PC board.
2. Verity unit is connected to the proper type gas. Example; if a natural gas unit, should be
connected to natural gas.
3. Verify low/high fire manifold pressures are set properly. See gas pressure setting procedures for
pressure setting at your elevation.
4. Clean sensor.
5. If unit was ever converted from one gas type to another, verify the conversion process was
preform per the manufacturer's instructions and all pressures and dip switch were set to match
the gas type unit was converted too.
6. Replace sensor
Code 57 Troubleshooting Procedure
Burner Overheat Bi‐metal Switch
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