High
24 on Maxol Supacombi HE 24

Your boiler has stopped working because it cannot confirm that harmful exhaust fumes are being safely cleared away, so the fan is running constantly as a safety precaution.

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

Erroneous APS signal, no flame and fan runs continuously - Missing or defective APS signal

From this model's manual
Verified against the Maxol Supacombi He 24 installation & service manual, page 28.
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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