High Lockout
C/H Sensor Fault on Ideal Concord CXC 48 116

Your boiler's temperature sensor has stopped working correctly, meaning the system can no longer tell how hot the water is and has shut down as a precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

If a fault occurs with the boiler thermostat the fault display screen will show "C/H Sensor Fault".

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring water temperature becomes damaged or loses its ability to send an accurate electrical signal. The most common reasons are electrical failure within the thermistor itself or corrosion on the wiring connections caused by years of heat cycling.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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