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

Your boiler has detected that it is getting too hot and has automatically shut down to prevent any internal damage.

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

Overheat Lockout. Go to Overheat Lockout section of the fault finding instructions.

From this model's manual
Verified against the Potterton Boiler Promax 30 He Plus 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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