Low
d.05 on Glow-worm Sustain 12s

This code is not actually an error; it simply displays the current temperature the boiler is trying to reach for your radiators.

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

Determined heating flow set target temperature

From this model's manual
Verified against the Glow Worm Sustain 12s installation & service manual, page 29.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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d.00View →d.04View →

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