What does the Vaillant P.01 fault code mean?

Your boiler has become stuck in a manual testing mode used by engineers and is likely failing to exit this program correctly.

How much does it cost to fix Vaillant error code P.01?

Typical repair cost for the Vaillant P.01 fault is £80-120 including labour.

Maximum load test program error

Turn the boiler power off at the main fused spur switchWait for 30 secondsTurn the power back on to see if the boiler resets to normal operation

Safety-critical — turn off, read this.

Break-even maths on monthly cover.

7 signs repair isn't worth it anymore.