High
0A1 on Alpha Pro Tec 24

Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water.

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

Ignition failure. Check for correct gas supply (purged and valves open). Check ignition electrode position and spark. Check flame sensing electrode connections. Check gas valve operation.

From this model's manual
Verified against the Alpha Pro Tec 24 installation & service manual, page 34.
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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