Trane CNT3719 Control

The Trane CNT3719 is a heavy-duty, single-pole single-throw (SPST) low pressure control switch engineered to protect the compressor from low-suction conditions and avoid thermal overloads. As a critical safety component in Trane HVAC systems, this switch monitors refrigerant levels and opens the circuit when pressure drops to 8 PSI, then automatically closes (resets) when pressure returns to 25 PSI. Built with a rugged IP65-rated casing, the CNT3719 is protected against dust and water ingress, ensuring reliable operation in the harsh environments of chillers, heat pumps, and refrigeration units.

For service technicians, this low pressure switch replacement features a standard 250 VAC, 6A electrical rating, making it compatible with most commercial and residential refrigeration circuit loads. Proper indexing of this system pressure monitor is vital for preventing "short cycling" caused by minor leaks or restricted evaporator coils. Whether you are performing HVAC repair on a split system or a large rooftop unit, installing the OEM Trane CNT3719 ensures the equipment maintains the exact cut-out and cut-in thresholds required for optimal refrigerant pressure monitoring.

• Enhanced Compressor Protection: Prevents catastrophic failure by opening the circuit at 8 PSI, protecting against low-charge operation and freeze-ups.
• Durable IP65 Construction: The weather-resistant enclosure is designed for long-term placement in high-vibration and outdoor service environments.
• Precise 8 PSI/25 PSI Thresholds: Specifically calibrated for HVAC applications to eliminate nuisance tripping while maintaining system safety.
• Universal Voltage Compatibility: Rated for up to 250 VAC, allowing for seamless integration into 120V and 240V control circuits.
• Compact Cartridge Design: Small footprint enables easier installation in tight service panels and suction line manifold configurations.

• What causes a Trane CNT3719 to trip? Typically, the switch opens due to a low refrigerant charge, a clogged filter-drier, or a frozen evaporator coil. If the pressure is above 25 PSI and the circuit remains open, the switch is likely faulty.
• Is the CNT3719 a manual or automatic reset? This specific model functions as an automatic reset, closing the circuit once the system pressure rises above the 25 PSI "make" threshold.
• Can this be used with R-410A systems? Yes, while settings may vary by application, this switch is a standard safety control for many Trane circuits, though tech specs should always be verified against the unit's wiring diagram.

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.