Cause of error code Er81

Low Water Level Circuit

Solution for error code Er81

This Error Code will go away when the condition is remedied.
If Error happens again:

- Ensure all valves are open to the boiler and there are no leaks.
- Check wiring connections to low water level sensor. Ensure all are secure.
- Check low water level sensor resistance. If resistance is zero, replace the sensor.
- If the problem persists, replace the main control.