High
70°C neon flashing on Potterton Performa 24

Your boiler is failing to vent exhaust gases properly because it cannot confirm that the flue fan is working as it should, so it has shut down for safety.

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.

What the manual says

Manufacturer manual

Go to section ‘E’ - Air pressure switch proved fault.

From this model's manual
Verified against the Potterton Boilerperforma24ihe installation & service manual.
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 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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