Low
26 on Main System 18 HE

Your boiler is simply completing its standard startup process and checking that all internal systems are ready to run.

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

Power On

From this model's manual
Verified against the Main System 18 24 28 He installation & service manual, page 8.
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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