Temperature sensor of condenser

The condenser temperature sensor is the feedback device that lets the controller manage head pressure and protect the compressor. When sensor 1851700100 drifts out of spec or goes intermittent, the unit can trip on high temperature, run the fan constantly, or throttle cooling at the wrong time. Techs see it as erratic head pressure control, nuisance alarms, and “not cooling” complaints that don’t match the mechanical condition of the condenser. A condenser sensor that reads high can force the fan to run full time and still shut down the compressor on a false over-temp condition. Check the basics: verify the sensor is firmly mounted in the intended location and that the harness isn’t pinched. Then compare sensor resistance to the expected value at the measured surface temperature. Intermittent sensors often fail a wiggle test values jump when you move the lead or connector, especially in high-vibration environments. Measure actual condenser surface temperature with a probe and compare it to the controller display; big deltas point to sensor drift. Replacing the condenser temperature sensor solves the problem by giving the control board accurate data again. With correct feedback, fan staging (or fan cycling) becomes predictable, head pressure stays in range, and the system stops shutting down prematurely. It’s the right move when the condenser is clean and airflow is good but control behavior says otherwise. Condenser temp sensor 1851700100 should be re-secured with the correct clip/contact method so it responds quickly to temperature changes. After replacement, verify the reading tracks actual temperature changes and run the machine through a full freeze in a normal ambient. Stable fan control and no surprise high-temp faults confirm the fix. After replacement, watch that the fan transitions smoothly rather than rapid cycling, which indicates stable feedback.