High
61. on Remeha Gas 610 Eco Pro

Your boiler is unable to start because it cannot confirm that the internal fan system is safe to move air through the flue.

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

Air transport. Air differential switch does not open: switch defective, extreme draft through flue gas discharge duct, or short-circuit in wiring.

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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