High
d.13 on Glow-worm Ultimate3 Combi

Your boiler is struggling to pump water to provide hot water to your taps, which means you likely have no hot water available.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Statusofthedomestichotwatercircuit'scirculationpump

From this model's manual
Verified against the Glow Worm Ultimate3 Combi installation & service manual, page 41.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

d.14View →F.73View →F.74View →

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