Exhaust NTC detects Vent Temperature is Greater than 149ºF / 65ºC
(190ºF / 87.8ºC when High Temp set point is Selected).
This Error Code will go away when the condition is remedied.
If Error happens again:
- Check if dip switch High Fire setting is ON. Switches 6 and 7 should be OFF for normal operation.
- Check exhaust temperature sensor. Ensure connections are secure.
- Check sensor resistance. If resistance is zero, replace the sensor.
- Check exhaust vent for blockage.
- If the problem persists, replace the control.
- If the problem persists, replace the heat exchanger.
