Water heater not starting altogether

Sometimes water heaters may fail to start on the first try. If you try to start the heater and nothing happens, follow these steps:

1. Check the voltage:
   Measure the voltage on the heater’s harness (pins 1 and 2 on the connector). Turn the heater ON and make sure the voltage remains correct.

2. Test manual startup:
   If the voltage is correct, try starting the heater by connecting the red and yellow wires together manually.

   • If this works, replace the controller (this applies only to newer-generation Espar heaters).

3. Check the ECU:
   If the heater still doesn’t start, the ECU may be locked, or the startup self-test may have failed.

4. Retrieve fault codes:
   Pull diagnostic codes from the controller or diagnostic tool, and submit a support ticket with Heatso. Please include detailed installation photos to help with troubleshooting.