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

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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

Shared across the Compact range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 →

All 143 fault codes on the Compact

Seeing a different code? Every code this model can display, in one place.

d.00d.01d.02d.05d.06d.08d.09d.10d.11d.13d.14d.15d.16d.17d.18d.20d.21d.22d.23d.27d.28d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.64d.65d.67d.68d.69d.71d.80d.81d.82d.83d.85d.88d.91d.93d.94d.96d.149d.165d.191d.192F.00F.01F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.33F.46F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.97P.00P.01P.03P.04P.08S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.41S.42S.46S.53S.54S.58S.76S.88S.91S.96S.98

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