High
AL 07 on Sime Ecomfort System Plus HE EV

Your boiler has overheated, prompting a safety switch to shut the system down to prevent damage.

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

Safety thermostat (TS) intervention — check sensor/thermostat connections; deaerate system; replace if damaged

From this model's manual
Verified against the Sime/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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Related fault codes

AL 01View →AL 02View →AL 06View →

All 9 fault codes on the Ecomfort System Plus HE EV

Seeing a different code? Every code this model can display, in one place.

AL 01AL 02AL 05AL 06AL 08AL 11AL 16AL 17

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