Medium
Block 85 on Atag Q 25CR

Your boiler is temporarily pausing because it cannot detect enough water moving through the system and is attempting to clear any trapped air bubbles automatically.

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.

Technical description

The control has not detected a water flow. The venting cycle is started. If during this cycle water flow is detected, the venting cycle is ended and the burner is released.

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 80View →Block 81View →

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