Medium
A1 on Atag Q 25CR

Your boiler is struggling because the temperature of the water returning to it from your radiators is not what it expects, which is causing it to pause operations to protect itself.

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

Return water temperature

From this model's manual
Verified against the Atag Q 25cr 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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