Low
d.09 on Heatline CaprizPlus 24a

Your boiler is simply communicating with an external room thermostat or smart controller to determine how hot the water should be.

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

Flow temperature set point from external eBus control

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We could not tie this code to a specific manual. Treat it as indicative only.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Boiler cover options

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All 111 fault codes on the CaprizPlus 24a

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

d.00d.01d.02d.08d.10d.16d.17d.18d.20d.22d.23d.33d.34d.35d.36d.40d.41d.44d.67d.68d.69d.71d.80d.81d.82d.83d.85d.93d.94d.96ErrF00F01F10F11F20F22F23F24F26F27F28F29F32F49F61F62F63F64F65F67F68F70F71F72F73F74F76F77F83F84F85F86P.01P.02P.03P.05P.06P.07S.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.35S.36S.37S.41S.53S.54S.58S.90S.92S.95S.96S.97S.98

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