Medium
CH sensor on Heatline S24 Compact

Your boiler has detected an issue with the temperature sensor on the central heating system, meaning it cannot accurately read how hot the water is.

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

Fault on CH sensor

From this model's manual
Verified against the Heatline/Heatline Compact 24 installation & service manual.
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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Related fault codes

DHW sensorView →F1View →F2View →

All 5 fault codes on the S24 Compact

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

Air Pressure SwitchDHW sensorOutdoor sensorOverheat Thermostat

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