MARS 43349 Pressure Switch

When you're troubleshooting a system that keeps short cycling or tripping on low pressure, the MARS 43349 Pressure Switch is the reliable fixed-setting solution you need in your truck. This SPST auto reset pressure switch is designed specifically for HVAC low pressure control, featuring a precise 35 PSI open (cut-out) and a 60 PSI close (cut-in) setpoint to protect compressors from vacuum damage and loss of charge. Built as part of the trusted Klixon 4-series, this switch features a hermetically sealed sensor and tamper-proof construction, making it an ideal choice for R22 systems and modern R410A applications where space is tight. It mounts directly on the tubing via a 1/4" female flare S.A.E. connection with an internal deflator, eliminating the need for extra capillary tubes that eventually leak. With 18-inch leads and a 100,000-cycle life at rated current, this normally open switch ensures your installs stay operational without unnecessary callbacks.

• Compact Direct Mounting: The 1/4" female flare connection allows for fast, leak-free installation directly onto the system's service port.
• Automatic Reset Logic: Eliminates manual resets by automatically closing the circuit once the system pressure rises back to 60 PSI.
• High Versatility: Engineered to handle voltages from 24V to 240V, making it compatible with a wide range of residential and commercial equipment.
• Industrial Durability: The hermetically sealed sensor is factory-calibrated and tamper-proof, ensuring the 35/60 PSI delta remains accurate over the life of the component.

Is the MARS 43349 compatible with R410A?
Yes, this switch is rated for use with both traditional refrigerants like R22 and high-pressure refrigerants like R410A within its specified 35 PSI to 60 PSI range.

How do I wire this into the control circuit?
The MARS 43349 uses 18-inch leads to integrate into the 24V or line-voltage safety loop. As an SPST normally open switch, it breaks the circuit on pressure drop (35 PSI) and resets on rise (60 PSI).

Does this switch require a separate schrader valve tool?
No, the 1/4" female flare fitting includes a built-in deflator, allowing it to actuate the system's schrader core automatically during installation.

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.