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

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Vaillant Ecotec Exclusive installation & service manual, page 54.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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