High
520 on Potterton Promax HE Store

Your boiler has detected an issue with the water pump that circulates heating around your home, meaning your heating and hot water may not work properly.

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

Pump

Shared across the Promax range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Related fault codes

133View →E133View →160View →

All 21 fault codes on the Promax HE Store

Seeing a different code? Every code this model can display, in one place.

205215220231235402530531535E20E28E50E110E119E125E130E131E133E160E193

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