40-974 Graded Sensor Air Temperature Fit for Thermo King CRR20 CRR40 40-871

40-974 Graded Sensor Air Temperature for Thermo King

The 40-974 Graded Sensor Air Temperature is a replacement thermistor sensor for Thermo King CRR20 and CRR40 refrigeration units, measuring air temperature to maintain precise cargo environments.

Overview

This 40-974 graded sensor air temperature monitors the air temperature in Thermo King CRR20 and CRR40 systems. The 40-974 graded sensor air temperature feeds readings to the control board, helping the unit respond to temperature changes. It is a suitable service replacement for the original 40-871 sensor in compatible units.

Built For Performance

• Graded resistor curve provides accurate temperature sensing for Thermo King CRR20 and CRR40
• Direct replacement for sensor part 40-871 in applicable systems
• Built with sealed housing to resist moisture and vibration in mobile refrigeration
• Simple two-wire connection for quick field installation
• Tested for stable output across the expected temperature range

Fits These Machines

• for Thermo King CRR20
• for Thermo King CRR40

On-The-Job Use

• Used in truck and trailer refrigeration to detect return air temperature
• Replaces worn or inaccurate 40-871 sensors in Thermo King units
• Supports preventive maintenance programs for reefer fleets

Specs At A Glance

Good To Know

Q: Is the 40-974 sensor an exact swap for the 40-871? A: The 40-974 is specified as a replacement for the 40-871, but verify your unit model and serial number because Thermo King made changes across production years.

Q: Can I install this sensor without special tools? A: Yes, typical installation requires basic hand tools and disconnecting the old wiring connector, then connecting the new sensor and securing it in the original location.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.