Low
d.81 on Glow-worm MicraCom

This code is simply an information display showing the total number of hours your boiler has spent producing hot water and is not an error at all.

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

Running time in domestic hot water mode

From this model's manual
Verified against the Glow Worm Micracom installation & service manual, page 42.
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

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

d.80View →d.82View →d.83View →

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