Errors

Boiler type WGRTCNG199

Error code Er:20

Cause:

High Limit Overheat Switch – Closed is Normal, Open is Fault.

Solution:

Press the Power button to clear the Error Code.
- Inspect the High Limit Overheat switch. Ensure proper connections.
- Check High Limit Overheat switch resistance. If resistance is zero, replace the switch.
- If the problem persists, replace the main control.