Medium
31 on Baxi Combi Instant 80/105 HE

Your boiler is struggling to correctly detect or manage the request for hot water, which usually means it cannot provide a consistent temperature at your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Domestic Hot Water Mode

From this model's manual
Verified against the Baxi Combi Instant 80 105 He Combi installation & service manual, page 6.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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