Error Code 37 is displayed only when the pre-mix unit is operating in Hybrid Hot Mode. This error occurs when the thermistor connected to the storage tank is unable to accurately detect the water temperature within the tank.
Please verify that the storage tank thermistor is properly connected to the wire harness and that the wire harness is securely connected to the circuit board.
In some cases, Error Code 37 may indicate a circuit board configuration issue. This can occur under the following conditions:
- The maintenance writer on the circuit board is set incorrectly.
- The circuit board (microprocessor) is malfunctioning.
If you received a replacement circuit board, please follow the directions included in the box to either transfer the programming data from the old board to the new one or manually program the new one. Otherwise, directions can be found in the service manual for the unit you are working on.
This error code can be reset by unplugging the heater for 30 seconds and then plugging it back in.
For further technical assistance call 866-766-7489 or use our Contractor Locator to find a local service representative.