High
Block 60 on Atag Q 25CR

Your boiler's internal settings have been incorrectly configured, preventing it from safely regulating its power output.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Incorrect parameter setting of the minimum or maximum power.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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