Temperature Sensor Therm C/ CA

Sensor measuring the water temperature at the outlet of the heating coil. Sends a signal to the thermostat that regulates the burner's operation.

Application

The sensor is fitted in the water line in the combustion chamber, measuring the current water temperature. Based on this measurement, the thermostat switches the burner on and off, keeping the temperature close to the value set on the thermostat knob.

Symptoms – when to replace

• Water temperature doesn't match the thermostat setting, despite a sound burner and sound regulating knob.
• The burner doesn't respond to changes in water temperature – it runs continuously or doesn't switch on at all.
• Unstable, fluctuating water temperature during operation, despite a constant thermostat setting.
• Visible physical damage to the sensor or its cable when disassembled.

How to choose the right part

Selection is based on reference number 44954 – it applies exclusively to the therm C and therm CA. The therm 7-15, therm 10-17, therm Starlet 3, therm-RP and therm 895-1/1165-1 models require a different sensor (44.954 1), despite an identical function.

When replacing the sensor, check that it's correctly seated in the water line and that the electrical connection to the thermostat is sound – an incorrect reading may result from a loose seating, not only from the sensor itself.

Compatibility

therm C 11/130, therm C 13/180, therm C 15/150, therm CA 11/130, therm CA 12/150, therm CA 15/120.

[faq]

Does the same sensor fit the therm 7-15 or therm 10-17?|No – these models require a different sensor (44.954 1), despite having the same water temperature measuring function. The numbers are not interchangeable between series.

The burner runs continuously despite reaching the set temperature – is that the sensor's fault?|That's possible – a damaged sensor can send an incorrect (too low) temperature reading to the thermostat, so the burner never receives the signal to switch off. It's worth comparing the actual water temperature with the thermostat's reading.

Does removing the sensor require draining water from the system?|Yes, replacement requires depressurizing the high-pressure system – it's best to shut off the water supply and release pressure by opening the gun before starting disassembly.

I replaced the sensor but the temperature problem persists – what else should I check?|Check the thermostat itself and its knob (44.153) – if the signal from the sensor arrives correctly but the burner still doesn't respond, the cause may lie in the thermostat rather than the sensor.

[/faq]