Medium
H.01 – .21 on Baxi EP

Your boiler is heating up too quickly when you turn on the hot water, causing it to shut down to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Temporary error – flow temperature increasing too fast in domestic hot water (DHW) mode, insufficient circulation or sensor error.

DIY fix possible

Check that your main water stopcock is fully openEnsure all isolation valves under the boiler are in the open positionSwitch the boiler off and back on again at the fused spur to reset the system

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