High
E125 on Baxi Assure

Your boiler has detected that water isn't moving through the system properly, which is causing it to stop to prevent overheating.

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

Flow/return sensor test — poor primary circulation

Shared across the Assure 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

E110View →E122View →E128View →

All 35 fault codes on the Assure

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

0000915202840100103104107110118125128133134135160304312321384BatE0E4E15E20E28E110E118E128E130E133E160

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