Mars M43965 Pressure Switch 590 418 Hp

The MARS M43965 is a high-pressure safety switch designed to open on a rise in pressure, providing critical protection for HVAC and refrigeration systems. This open-on-rise pressure switch monitors system pressure and interrupts the circuit when pressure exceeds the set point, protecting compressors and related components from damage caused by abnormal pressure conditions. It is installed by licensed HVAC and refrigeration technicians as part of a system's safety control circuit. The M43965 is rated for high-pressure applications and is identified by set points of 590 and 418, making it suitable for demanding refrigeration and air conditioning service work.

This pressure switch is used in residential and commercial HVAC and refrigeration systems where high-side or safety pressure monitoring is required. It is typically wired into the control circuit to cut power to the compressor or system when pressure rises beyond acceptable limits, preventing equipment failure and protecting refrigerant circuits. Technicians install this switch as part of routine system maintenance, compressor replacement, or safety control upgrades.

Key Features

• Open-on-rise operation interrupts the circuit when pressure exceeds the set point
• Set points of 590 and 418 for high-pressure safety control applications
• Designed for integration into HVAC and refrigeration safety control circuits
• Provides compressor and system protection against abnormal pressure conditions
• Compact design suitable for installation in standard refrigeration and air conditioning equipment

Compatibility

Designed as an OEM-style replacement pressure switch for residential and commercial HVAC and refrigeration systems requiring open-on-rise high-pressure safety switching.

Installation Notes

Installation should be performed by a licensed HVAC or refrigeration technician in accordance with applicable mechanical codes. Shut down the system and relieve system pressure before disconnecting or replacing any pressure switch. Verify that wiring connections are secure and that the replacement switch matches the required pressure set points before returning the system to operation. Always follow the equipment manufacturer's wiring diagram when integrating the switch into the control circuit.