How a Thermal Expansion Valve Adds Greater Efficiency

How a Thermal Expansion Valve Adds Greater Efficiency to Your Air Conditioner

Oct 8, 2013
outside of home

Air conditioning is essential in our Central Florida region, and the more efficiently your A/C operates the better. To maximize cooling efficiency when you’re replacing or improving your cooling system, make sure the A/C is equipped with a thermal expansion valve. A thermal expansion valve (TXV) will increase the efficiency and extend the life of your air conditioner, while reducing your energy bills.

All air conditioners and heat pumps have an expansion element in their refrigeration cycle that controls the flow of refrigerant in the system. If your air conditioner does not have a thermal expansion valve, it likely has either a fixed orifice or capillary tube. These types of expansion controls allow a set flow of refrigerant into the indoor evaporator coil that removes heat from the home interior. They operate for average temperature conditions and cannot change the flow of refrigerant to meet changing temperatures. If too much refrigerant passes through the evaporator during cooler temperatures, liquid refrigerant may reach and damage the compressor. On the other hand, too little refrigerant may reach the evaporator coils during higher temperature conditions, reducing the ability of your air conditioner to maintain the desired indoor temperature.

Thermal expansion valves are designed to precisely control the flow of refrigerant into the evaporator coils in response to changing temperatures. A sensor in the TXV detects a change in temperature of the refrigerant gas at the evaporator coil outlet and opens the TXV to allow more refrigerant into the coils if the temperature rises, or partially closes the TXV outlet to reduce the refrigerant entering the coils when the temperature drops. The cost to add a thermal expansion valve to your air conditioning unit is relatively small and should be offset by cost savings over a couple of cooling seasons.

For more information about thermal expansion valves for your air conditioning system, please contact us at Rinaldi’s Energy Solutions. We have provided air conditioning installation and repair services to Orlando and Central Florida since 1969.

Our goal is to help educate our customers in Orlando, Florida and surrounding areas about energy and home comfort issues (specific to HVAC systems).  For more information about thermal expansion valves and other HVAC topics, download our free Home Comfort Resource guide.

Image courtesy of Shutterstock