BoilerFaultCodes.com
25 High

Your boiler is getting too hot too quickly and is shutting itself down to prevent damage.

Technical description: Boiler operates with high boiler water temperature
Typical repair cost: £150-450 (including labour)

DIY fix possible

Check that your radiator valves are fully openEnsure the central heating pump is runningCheck if the system water pressure is between 1.0 and 1.5 bar

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