For the quick, cut to the chase version, turning the adjustment on the bottom of an adjustable valve clockwise equals higher superheat while turning it counterclockwise equals lower superheat. However, before you start messing with the adjustment, I suggest you read on.

This line for hydrocarbon (HC) refrigerant (R290/R600a) use includes electronic expansion valves (EEVs), thermostatic expansion valves (TXVs), reversing valves, check valves, ball valves, and solenoid valves.

A thermostatic expansion valve (TXV) is designed to maintain a specific amount of superheat at the outlet of the evaporator. If the superheat value is too high or too low, the TXV may be the cause. However, before deciding the TXV is defective, all other system causes must first be investigated and ruled out.

The correct placement and installation of the thermostatic expansion valve (TXV) sensing bulb is important to its overall performance and reliability. An incorrectly installed or placed sensing bulb can lead to several different types of system problems. Here are some general installation concerns and tips to follow when installing a TXV.

The HVAC industry has seen a significant increase in thermostatic expansion valve (TXV) usage in the past decade. Even though TXVs are the most popular metering devices for residential air conditioning systems, there is still a lack of knowledge about TXV functionality in the market.

A few weeks back, The NEWS began chasing down this story. We dug through the smoke and discovered a fire. 

The thermostatic expansion valve (TXV or TEV) is a metering device located between the liquid line and the evaporator.