Low
S.31 on Heatline CaprizPlus 24a

Your boiler is currently set to run the hot water only, meaning your central heating is temporarily disabled by the user settings.

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

"Hot water only" mode

Community-sourced, unverified
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.

DIY fix possible

Locate the mode selector button or knob on the control panelSwitch the setting from 'Hot Water Only' (Summer Mode) to 'Heating and Hot Water' (Winter Mode)Check that your room thermostat is turned up to call for heat

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Related fault codes

S.30View →S.34View →

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.09d.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.32S.34S.35S.36S.37S.41S.53S.54S.58S.90S.92S.95S.96S.97S.98

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