High
Flash On Flash on Potterton Promax 15/2 HE Plus

The internal computer that controls your boiler has experienced a permanent error and is no longer able to give instructions to your heating system.

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.

Technical description

PCB Fault - Replace PCB.

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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Related fault codes

E119View →E133View →

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