Medium
H.01 – .21 on Baxi Profile Prima

Your boiler is heating up too quickly and has shut down temporarily to prevent overheating, likely because water isn't moving through the system fast enough.

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 all radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 barCheck for any visible leaks around the pipeworkRestart the boiler to see if the temporary fault clears

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