Medium
40 on Johnson Starley Comet 100

Your boiler has detected too much water pressure in the system, which can cause the safety valve to leak or the unit to stop working.

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

High system water pressure

DIY fix possible

Check that the filling loop valves are tightly closedBleed water from a radiator using a bleed key to reduce pressureMonitor the pressure gauge to ensure it returns to between 1 and 1.5 barReset the boiler once the pressure is stabilised

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