Medium
d.90 on Glow-worm Compact

Your boiler is having trouble communicating with your room thermostat, which means it might not know when to turn your heating on or off.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Status of the eBUS room thermostat

From this model's manual
Verified against the Glow Worm Compact 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

Check your room thermostat has fresh batteriesEnsure your thermostat is switched on and showing a displayTurn the boiler off at the fused spur for 60 seconds and switch it back on to reset the connection

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Related fault codes

d.91View →d.92View →F.76View →

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