High
117 on Atag S 25CR

Your boiler has stopped working because the water pressure inside the system has risen too high, likely due to a faulty filling loop or a system issue.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Water pressure is too high (> 3.0 bar). The boiler is taken out of operation.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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