Low
105 on Atag S 25CR

Your boiler is automatically running a short seven-minute cycle to remove trapped air from the system after it detected low water pressure.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

De-aeration program will start (approx 7 mins) after refilling if pressure was below 0.7 bar.

DIY fix possible

Wait for the seven-minute de-aeration cycle to complete automaticallyEnsure your system pressure remains between 1.0 and 1.5 bar on the gaugeMonitor the boiler for a few minutes to see if normal operation resumes once the cycle finishes

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