Copeland 985-0109-00 Probe

The Copeland 985-0109-00 is a specialized thermistor probe engineered for the Copeland Demand Cooling system, primarily used in low-temperature refrigeration applications using R-22, R-407A, R-407F, or R-448A/449A. This discharge temperature sensor monitors high-side heat directly at the source, signaling the injection valve to provide liquid refrigerant cooling when temperatures exceed safe operating limits. Proper installation of this replacement refrigeration probe is critical for protecting Discus compressors from oil breakdown and valve plate failure caused by excessive discharge heat. Designed for precise resistance-to-temperature correlation, the 985-0109-00 ensures the module receives accurate data to maintain the compressor within its approved operating envelope. This sensor is a vital component for low-temp rack systems where high compression ratios frequently lead to thermal stress. Replacing a fouled or drifted probe restores system reliability and prevents nuisance trips or compressor overheating.

• Precision Thermal Sensing: Calibrated for high-temperature monitoring to trigger liquid injection at specific setpoints.
• OEM Compatibility: Drop-in replacement for Copeland 985-0109-00 and compatible with standard Demand Cooling modules.
• System Protection: Actively prevents compressor overheating by providing real-time feedback to the injection solenoid.
• Durable Construction: Built to withstand the harsh environment of a refrigeration compressor discharge port.
• Critical Low-Temp Support: Essential for maintaining efficiency in R-448A and R-407A retrofits where high discharge temperatures are common.

How do I test the 985-0109-00 probe for accuracy?
Using a multimeter, you should measure the resistance across the probe leads and compare the reading to the Copeland resistance-temperature chart. An open circuit or a reading that deviates significantly from the ambient temperature resistance indicates a failed sensor.

Can this probe be used on any Discus compressor?
This probe is specifically designed for compressors equipped with a Demand Cooling module. It is typically installed in the head of the compressor to monitor discharge gas temperature.

What causes these probes to fail prematurely?
While durable, Demand Cooling sensors can fail due to moisture ingress, wire vibration causing an open circuit, or extreme thermal cycling if the compressor is frequently operating at the edge of its limit.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.