Compensating for Changing Heat Load with a Thermal Expansion Valve

thermal_expansion_valveMany electrical enclosures are located in environments that change drastically throughout seasons, or even within the same day. When temperatures swing from one extreme to another, your enclosure cooling system must be able to keep up. An integrated thermal expansion valve is the best way to ensure that an enclosure air conditioner operates at peak performance no matter what the external temperature is.

Thermal Expansion Valves for Heat Load Variations

A thermal expansion valve is designed to modulate the flow of refrigerant through an air conditioning system. When the heat load is high, the valve allows more refrigerant to flow to ensure that your valuable electrical components do not overheat. When the heat load is reduced, the valve reduces the flow of refrigerant to improve efficiency.

Purchasing an enclosure air conditioner with a thermal expansion valve provides the following benefits:

  • Better efficiency – Adjustable refrigerant flow enables better efficiency over a wider temperature range. Systems that use a fixed capillary tube system can lose up to 85% of evaporator efficiency in large temperature variations. This factor can be reduced by more than one half with a thermal expansion valve.
  • Better protection of components – An air conditioner that is not able to automatically adjust the flow of refrigerant to the evaporator may not be able to handle the high temperatures to which an enclosure might be exposed. This can lead to insufficient cooling and overheating of the compressor. When the temperature is below the nominal design point of a capillary tube, liquid slugging can occur. Both conditions can ultimately damage the compressor. This can be expensive not only in terms of the cost to replace the air conditioner, but can also result in electrical equipment failure and stopped operations.
  • Better long-term performance – A critical component of air conditioner maintenance is ensuring that the refrigerant charge is correct. This is especially important for smaller units. While refrigerant charge is not inconsequential for air conditioners that employ a thermal expansion valve, they can tolerate more variations because the valve is constantly adjusting the flow. This means that even if the refrigerant charge drops between maintenance activities, the unit is less affected.

Every Thermal Edge air conditioner is equipped with a thermal expansion valve to accommodate a broad range of potential applications. Whether your enclosure is exposed to daily temperature swings or seasonal shifts in the weather, you want to be sure that the components inside are protected. Thermal Edge enclosure cooling systems are designed to withstand sudden and significant changes in the heat load to ensure that they will perform in demanding environments.

Contact us today to learn more about why thermal expansion valves are important and how they can help you protect your valuable assets.