Low
S.34 on Glow-worm Ultimate3 System

Your boiler is temporarily running its pump to prevent the water inside from freezing because the temperature has dropped very low.

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

Frost protection active

From this model's manual
Verified against the Glow Worm Ultimate3 System installation & service manual, page 43.
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

Ensure your boiler is switched on at the power supply.Check that your external thermostat or smart controller is set to a reasonable temperature.Wait for the temperature to rise, as the boiler will stop this process automatically once it warms up.

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