High
125 on Baxi 630 Combi

Your boiler has detected that the water inside the system is either not heating up properly or is getting far too hot, very quickly.

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

is displayed in either of two situations: If between 15 and 30 seconds of the burner lighting, the primary water temperature has not changed by 1° C. If within 10 minutes of the burner lighting, the primary water temperature actual temperature twice exceeds the selected temperature by 30°.

From this model's manual
Verified against the Baxi/Baxi 636 Combi Lpg 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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Related fault codes

E119View →E133View →

All 17 fault codes on the 630 Combi

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

0915202840109110118128130133134135160321384

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