Thermal Expansion Valve vs. Capillary Tube for Electrical Enclosure Air Conditioners

Enclosure air conditioners are important for protecting electrical components from heat and humidity. To help maintain a suitable temperature in the enclosure, air conditioners circulate refrigerant from a compressor through a condenser and an evaporator and back to the compressor.

The refrigerant arrives in the compressor as a cool gas, which is then compressed to a high-pressure gas that is passed on to the condenser. In the condenser, the gas is converted to a liquid that then flows through to the evaporator. As the liquid evaporates back into a gas to continue the cycle, it draws heat from the surrounding air in the enclosure, which has the effect of lowering the temperature.

Optimal refrigerant flow is clearly a critical component of any air conditioner. The flow of refrigerant into the evaporator is controlled with an expansion device, which can either be a passive capillary tube or an active thermal expansion valve.

Although these two systems both control the flow of refrigerant, they work in different ways. A thermal expansion valve can respond to the environment by increasing or decreasing the flow of refrigerant as necessary, while a capillary tube is a fixed system that does not fluctuate with heat load changes.

Thermal Expansion Valve vs Capillary Tube in Air Conditioners

Some of the advantages of a thermal expansion valve vs a capillary tube include:

• Better efficiency – As temperatures fluctuate over time, a thermal expansion valve can adjust the refrigerant flow to accommodate a larger or smaller heat load. This allows the unit to operate more efficiently.
• Broader temperature range – When the ambient temperature increases, the cooling system has to work harder. A thermal expansion valve can increase the flow of refrigerant to provide better cooling at higher temperatures. This flexibility also prevents liquid slugging, which can damage compressors.
• Larger refrigerant charge range – Having the right refrigerant charge is important for optimal performance, especially when the system uses capillary tubes. Thermal expansion valves allow for a greater variation in refrigerant charge without impacting performance.

If you would like to learn more about the benefits of a thermal expansion valve vs a capillary tube, contact the experts at Thermal Edge. Every Thermal Edge air conditioner uses a thermal expansion valve to ensure the best performance. Each of our units also evaporate condensate to prevent dripping water from the air conditioner. If protecting electrical enclosures is a priority for you, contact us today to get a free quote.