Medium
Block 67 on Atag Q 25S

Your boiler has detected that water is circulating unexpectedly while it is trying to stay idle, so it has paused itself to prevent damage until the temperature settles.

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.

Technical description

A ΔT has been detected between flow and return sensor whereas the burner is not in operation. After the ΔT has disappeared the block will disappear.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Block 60View →

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