Low
18 on Baxi 124 Combi

Your boiler has switched into a specific mode intended for systems connected to solar panels, which usually happens due to a settings error or a sensor detecting an unusual temperature.

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

Solar plant operating mode

From this model's manual
Verified against the Baxi 124 Combi Combi 2 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

Press and hold the Reset button for 5 secondsTurn the power to the boiler off at the fused spur switch, wait 30 seconds, and turn it back onCheck if the boiler has been accidentally put into a solar-only mode via the control panel

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