Low
100 on Baxi 624 Combi

Your boiler is currently running at its highest power setting for a service test and is not actually reporting a hardware 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 624 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.

DIY fix possible

Wait approximately 15 to 20 minutes for the test to time out automatically.Turn the selector dial or power button off and then back on to reset the mode.Check that the chimney sweep switch or setting has not been accidentally activated on the control panel.

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