High
AL 74 on Sime Brava One HE

Your boiler has detected an issue with a temperature sensor that monitors the water being sent to your taps or radiators, meaning it cannot accurately gauge the water heat.

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

Fault in the 2nd element of the delivery sensor — check second NTC sensor position and wiring

From this model's manual
Verified against the Sime/Sime Brava One He installation & service manual.
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 05View →AL 14View →AL 15View →

All 49 fault codes on the Brava One HE

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

06AL 00AL 01AL 02AL 03AL 04AL 05AL 06AL 07AL 08AL 09AL 10AL 11AL 12AL 13AL 14AL 15AL 18AL 28AL 30AL 37AL 40AL 41AL 42AL 43AL 44AL 56AL 57AL 62AL 72AL 77AL 78AL 79AL 80AL 81AL 82AL 83AL 84AL 88AL 89AL 90AL 92AL 93AL 95AL 96AL 98AL 99SE

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