Low
S.46 on Glow-worm Ultimate3 System

Your boiler has temporarily paused to protect itself because the flow of water inside is too low, often caused by closed radiators or a struggling pump.

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

Protection mode: Minimum load

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

Check that at least one radiator valve is fully open in the same room as your thermostatEnsure all individual radiator valves around your home are open and not stuckCheck that your system pressure is within the green range (usually 1.0 to 1.5 bar) and top up if necessary

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S.45View →F.22View →

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