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.

What the manual says

Manufacturer manual

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.

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

Engineer required

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

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