Medium
S.53 on Heatline Compact 30

Your boiler has paused its heating process because the water circulating through your radiators is not returning to the unit quickly enough, often due to a blockage or restricted flow.

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

Waiting cycle: temperature differential between heating fl ow and return is too high. If ∆T > 30, forcing to Pmin

DIY fix possible

Check that your radiator valves are fully open throughout the houseEnsure your thermostat is set correctlyBleed your radiators to remove any trapped air that may be causing a blockage

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