Medium
Block 01 on Atag Q 25S

Your boiler has stopped because an external safety device, such as a fire alarm or frost thermostat, has told the system to shut down for safety reasons.

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

External safety contact cut off

From this model's manual
Verified against the Atag Q 25s installation & service manual, page 39.
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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