Rinnai HE Series How To Use Manual page 186

1. Check wiring harness at burner thermocouple back to PC board for loose, broken or damaged
wiring or connections.
2. Verify all dip settings are set to the proper alitiube per the tech sheet found under the front
panel of your unit. This information can also be found in the product's service manual.
3. Confirm low/high fire manifold gas pressures are set to factory specification per alitiube unit is
installed at. Manifold gas pressure settings and directions can be found on the tech sheet under
front panel of the unit or in the service manual.
4. Replace burner thermocouple. If code reappears after replacing this component replace PC
board.
Code 73 Troubleshooting Procedure
Burner Thermocouple Fault
34