Medium
EF 349 on Worcester Bosch 26 CDi Xtra

Your boiler is slowing itself down because water isn't moving through the system quickly enough to take the heat away.

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

Central heating boil detected – boiler operating at minimum burner load with temperature difference greater than 18°C between Flow & Return.

DIY fix possible

Check that all radiator valves are fully openEnsure the boiler pressure gauge is between 1.0 and 1.5 barCheck if the pump is making a humming sound or if it feels excessively hot

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