Emergency
ER 5 on Ferroli Xignal

Your boiler is struggling to clear exhaust gases due to a blockage in the air vent pipes or a faulty safety sensor.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

FAULT AIR PRESS SWITCH - Defective pressure switch or clogged tubes

Engineer required

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

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Related fault codes

F37View →

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