Low
d.16 on Glow-worm Flexicom 24c / 28c

Your boiler is currently waiting for a signal from your room thermostat to tell it that your home needs heating.

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

Status of the 24V room thermostat (ON/OFF)

Shared across the Flexicom 24c / 28c 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 is set to a temperature higher than the current room temperature.Ensure the thermostat batteries are fresh and the device has power.Verify the thermostat is not set to 'Summer' or 'Off' mode.

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Related fault codes

d.14View →d.15View →

All 141 fault codes on the Flexicom 24c / 28c

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.17d.18d.20d.21d.22d.23d.27d.28d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.62d.64d.65d.67d.68d.69d.71d.80d.81d.82d.83d.85d.88d.90d.93d.94d.96F.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.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.97F01F10F11F13F17F20F22F25S.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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