Low
Yellow LED On every 0.5 second on Halstead iHeat 24c

Your boiler is currently stuck in a professional testing mode, which is usually only used by engineers to check for proper combustion.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Service function

From this model's manual
Verified against the Halstead Iheat 24c 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.

DIY fix possible

Locate the selector switch on the front control panel.Ensure the dial is pointed firmly to either 'On' or 'Standby' and not left in the service/test position.Turn the boiler off and back on at the fused spur switch to reset the sequence.

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