High
Lights: Off Off Off on Potterton Promax Heat Only

Your boiler has completely lost power and is unable to turn on because it is not receiving any electricity.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Failure of electrical supply. Check 240V at terminal block and PCB fuse.

From this model's manual
Verified against the Potterton Promax He Store installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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