Alpha Temperature Sensor NTC 1.021762

The Alpha 1.021762 is an NTC temperature sensor used across a wide range of Alpha appliances, including the 240, 280, 500, CB, CD and SY families. It is a negative temperature coefficient thermistor, meaning its electrical resistance falls as the sensed temperature rises, allowing the appliance's control board to read temperature accurately and regulate operation. It is listed under the spare part group Thermostats, Thermistors & Sensors.

• The appliance locks out or fails to fire, with a temperature-related fault code logged
• Domestic hot water runs hot and cold, or the delivered temperature no longer matches the setting
• The boiler short-cycles or modulates erratically because the control board is receiving an implausible reading
• Heating or hot water is intermittent, or the appliance shuts down shortly after ignition
• A resistance check across the sensor falls outside the expected range for the temperature being measured

• Confirm the appliance GC number or model and serial number against the compatibility list, as the same sensor body is used across several Alpha ranges
• Check the previous part numbers listed below against the sensor fitted to your appliance, as earlier numbers have been used in the same position
• Inspect the sensor pocket, retaining clip and any sealing washer on removal, and replace them if they are damaged or perished