Medium
S.57 on Vaillant ecoTEC exclusive

Your boiler is currently taking a short break to automatically re-calibrate its internal settings, during which it will temporarily pause heating and hot water production.

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 time: Measuring program (Calibration unsuccessful. Waiting period, comfort protection mode)

DIY fix possible

Wait up to 15 minutes for the boiler to complete its automatic calibration cycle.If the code persists, press the reset button (flame symbol with a cross).Monitor the boiler to see if it returns to normal operation after the waiting period.

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F.20View →F.22View →F.27View →

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