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S.34 on Glow-worm Essential

Your boiler has detected very cold temperatures and is running its pump to prevent your pipes from freezing.

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

Frostprotectionactive

From this model's manual
Verified against the Glow Worm Essential installation & service manual, page 34.
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

Wait for the temperature to rise, as this is a protective feature rather than a fault.Ensure your heating controls are set to a temperature that keeps your home warm during cold spells.Check that your boiler is not located in an unheated space like a garage, which may need extra insulation.

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Related fault codes

S.33View →S.35View →

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