Low
GREEN LED FLASHING on Halstead Ace High

Your boiler is perfectly healthy and is simply waiting for a signal from your thermostat or hot water tap to start heating.

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.

Technical description

Boiler in standby mode (Power on)

DIY fix possible

Turn up your room thermostat to a temperature higher than the current room temperature.Ensure your heating timer or programmer is set to 'On' for the current time.Check that you have not accidentally pressed the 'Off' or 'Summer' mode setting on your boiler controls.

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