Medium
S.57 on Vaillant Combi Compact 242EB

Your boiler is temporarily pausing to prevent overheating after reaching a high temperature, often due to a lack of proper water 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 period comfort safety mode

DIY fix possible

Check that all radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 bar on the gaugeWait up to 15 minutes for the 'comfort' delay period to end automatically

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Related fault codes

S.53View →S.54View →F.20View →

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