Lennox 12J18 TXV Kit

The Lennox 12J18 TXV Kit is a critical OEM component designed for high-precision refrigerant metering in residential and light commercial cooling systems. This thermostatic expansion valve (TXV) is specifically engineered for R410A refrigerant applications, accommodating a capacity range of 1.5 to 3 tons. For technicians performing a coil replacement or upgrading a fixed orifice system, the 12J18 ensures optimal subcooling by utilizing an external equalizer to monitor evaporator outlet pressure. This responsiveness prevents liquid slugging and evaporator freeze-ups, maintaining the SEER rating efficiency of the outdoor unit. As a genuine Lennox replacement part (104110-05), it offers a direct fit for compatible air handlers and uncased coils, eliminating the need for extensive field modifications. By balancing the mass flow rate against the cooling load, this valve provides the consistent superheat control necessary for modern high-efficiency HVACR installations.

Key Benefits

• Ensures precise refrigerant flow control to maximize heat transfer efficiency across 1.5-3 ton A/C systems.
• Compatible with a wide range of Lennox air handlers and evaporator coils using R-410A.
• Features an external equalizer line for accurate pressure sensing and improved system reliability.
• Optimizes performance during varying ambient temperatures, preventing compressor damage.
• Direct OEM replacement ensures factory-spec fitment and long-term mechanical durability.

Common Questions

Is the Lennox 12J18 compatible with systems larger than 3 tons?
No, this specific kit is rated for 1.5 to 3-ton R410A capacities. Installing this on a higher tonnage system will result in refrigerant starving and poor cooling performance.

Does this kit include the sensing bulb and mounting hardware?
Yes, as a complete TXV kit, it includes the valve body, a sensing bulb, and the necessary clips for securing the bulb to the suction line.

Can I use this valve for an R-22 to R-410A conversion?
This valve is designed exclusively for R410A refrigerant. It must not be used with R-22 due to different pressure requirements and lubricant compatibility.

This item is not eligible for free shipping.

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.