Low
100 on Baxi Combi Instant 80/105 HE

Your boiler is currently in a manual testing mode used by engineers to check combustion levels, rather than displaying a fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Indicates boiler is operating at maximum output during chimney sweep mode.

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

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Boiler cover options

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