Medium
Block 67 on Atag Premier

Your boiler has detected an unexpected temperature difference between its internal pipes while it is turned off and is currently holding to prevent system strain.

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 (cid:1)T has been detected between flow and return sensor whereas the burner is not in operation. After the (cid:1)T 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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