Low
d.58 on Glow-worm Ultimate3 Combi

Your boiler is currently waiting for a signal from an attached solar water heating system that is not providing the expected input.

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

Solarcircuitreheating

From this model's manual
Verified against the Glow Worm Ultimate3 Combi 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.

Engineer required

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

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Related fault codes

d.57View →d.59View →

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