High
0A16 on Alpha Pro Tec 24

Your boiler is struggling to heat the water quickly enough, so it has stopped working to prevent itself from overheating.

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

Flow sensor temperature rise incorrect. The time taken for the flow temperature to rise is too great.

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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