Medium
Block 67 on Atag Q 25CR

Your boiler has detected an unusual temperature difference inside the system while the heating is turned off, so it has paused its operation to prevent any potential damage.

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 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.

Shared across the Q 25CR range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Related fault codes

Block 60View →

All 53 fault codes on the Q 25CR

Seeing a different code? Every code this model can display, in one place.

000102040510111218192028405060676980818285A0A1A4A5A9Block 01Block 11Block 12Block 60Block 80Block 81Block 82Block 85COdEError 00Error 01Error 02Error 04Error 05Error 12Error 18Error 19Error 28Error 69Error 80FILLGoodHIGHP x.xStBYSTOP

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