Medium
S.39 on Vaillant Combi Compact 242EB

Your boiler has temporarily stopped heating because a safety sensor or an external pump has detected an issue and cut the power to the burner.

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

Burner off contact has been triggered this could be because of contact thermostat or condensate pump

DIY fix possible

Check if your condensate pump (if you have one) is plugged in and turned on.Ensure the pipe leading from the condensate pump to the outside or drain is not blocked or frozen.Reset the boiler by turning it off and on again to see if the status clears.

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Related fault codes

S.30View →S.31View →

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