High
AL 16 on Sime Ecomfort Plus HE EV Combi

Your boiler has failed to ignite because it cannot detect the water heating up as expected, causing it to 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

HEATING PROBE POSITIONING ERROR SM1/SM2 If the heating probe sensor does not detect a temperature rise within 10 seconds after a burner ignition

From this model's manual
Verified against the Sime Ecomfort Plus He Ev Combi 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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