An air conditioning system comprises a wide array of components. Each component plays a vital role in ensuring that your unit keeps your living space cool while operating optimally and efficiently. You may be familiar with some of the components, but there might be others you’ve never heard of at all.

When purchasing a new AC, there are different features that can influence your unit’s efficiency and performance levels that you need to consider. Since adding some advanced features may sometimes increase the cost of a brand-new air conditioner, it’s crucial to know the function of each feature and whether it’s worth the added cost or not. Today, we will talk about one of the AC’s advanced features, the thermostatic expansion valve, and how it can benefit your home.

What Are Thermostatic Expansion Valves?

A thermostatic expansion valve, or thermal expansion valve, refers to the air conditioning or refrigeration throttling device that regulates the amounts of refrigerant injected into a unit’s evaporator. The amount of refrigerant depends on the evaporator’s outlet pressure and temperature, also called the superheat.

A thermostatic expansion valve is known as the TX valve, TXV, or TEV. It is utilized in systems of high capacities, such as central air conditioners, packaged air conditioners, high-capacity air conditioning units, and industrial refrigeration units.

Main Components of a TXV

A thermal expansion valve has a wide range of components. The valve body holds all the components of the valve and the orifice that restricts the refrigerant’s flow. The needle or pin moves downwards and upwards to control the opening of the orifice to help regulate the flow of the refrigerant. The diaphragm is a thin and strong flexible metal material that flexes to apply some pressure to the needle. The spring counteracts the pressure of the pin. Finally, there are the capillary line and sensing bulb. These parts measure the temperature of the refrigerant at the evaporator’s outlet and react to close or open the valves.

How Thermal Expansion Valves Work

An air conditioning unit has indoor coils called evaporator coils. These coils absorb heat from the air in your home and transfer it to the refrigerant liquid that flows through the AC unit. When the indoor temperature becomes warmer, the temperature of the refrigerant liquid that leaves the unit’s evaporator coils will be a bit higher.

Depending on your home’s cooling needs, the TXV works by regulating the refrigerant amount that flows from the AC’s evaporator coils to the compressor. The valve works by reading the refrigerant’s temperature within the evaporator coils and utilizes that temperature level to determine the amount of refrigerant liquid that goes into the compressor.

When the refrigerant’s temperature rises, the TXV will open up to let in more refrigerant liquid into the compressor. However, if the temperature is low, the valve will close up and restrict the refrigerant’s flow, allowing a lesser amount of the liquid into the system’s compressor.

Types of Thermostatic Expansion Valves

The TXV often comes in two different types: internally and externally equalized. The internally equalized valves experience pressure at the inlet or intake of the evaporator and utilize the pressure at the intake to close the valve. These expansion valves are used in evaporators with high pressure drops to help control the unit at a high superheat.

On the other hand, evaporator pressure in externally equalized valves is found at the outlet of the evaporator. An externally equalized TXV utilizes the outlet pressure of the evaporator, which makes up for the pressure drops through your AC unit’s evaporator.

Benefits of TX Valves

The role of a TXV is to ensure that the refrigerant liquid is flowing into your AC’s evaporator at the appropriate rate to help maintain a consistent superheat. Modern AC systems have a minimum efficiency of 13 SEER. A TXV keeps your air conditioner running efficiently and optimally while protecting the unit’s compressor from damages caused by the refrigerant. Below are the advantages of a TXV.

Keeps the Evaporator in Optimal Performance

The TXV allows the refrigerant to flow based on the cooling load within it. The refrigerant flow is reduced at lower loads and increased at higher loads. The TXV allows the AC unit’s evaporator to run according to the requirements. The valve constantly regulates the refrigerant flow to maintain the adjusted superheat. As a result, the valve enables the evaporator to remain active during the entire cooling process. The TXV ensures that your unit’s evaporator performs optimally by continually regulating the refrigerant flow to match the changed superheat.

Eliminates Compressor Breakdown

If large amounts of refrigerant go to your air conditioner’s compressor, it can damage the component and cause system breakdowns that are costly to repair. A thermostatic expansion valve allows for the complete vaporization of refrigerant liquid within the evaporator. This process eliminates refrigerant slugging and prevents the liquid particles from reaching the air conditioner’s compressor, extending the life of your unit.

Handles Refrigerant Charge Variations

The refrigerant level within the cooling loop is an important parameter that can impact the overall performance of your AC. That is especially true if it comes with a passive expansion gadget such as a capillary tube. A TXV is more tolerant of refrigerant charge variations because it adapts its flow to balance the heat load. That prevents the liquid refrigerant from flooding the compressor. It also allows for an instant response to a decrease or increase in the heat dispelled by your AC unit.

Efficiency Levels

The compressor is one of the air conditioner parts that consume a lot of energy when your unit is running. The compressor will work less and consume less energy by regulating the refrigerant amount that goes into the compressor when your cooling demands are lower. As a result, your unit’s overall efficiency levels will improve, saving you a lot of money in the long term.

Better Temperature Control and Consistent Cooling

Because a TXV is constantly measuring the temperature level of the refrigerant within the evaporator coils, it continually adjusts the AC’s refrigerant flow based on the cooling demands of your living space at a given time. These valves are also fairly responsive. The unit will quickly register the change once you adjust the air conditioning system’s temperature using your thermostat. This way, your AC unit will become more responsive and adaptable to your cooling needs. As a result, the AC unit will have the capacity to provide your home with more consistent temperatures throughout the day and night.

Contact the Air Conditioning Experts

This guide has given a comprehensive description of the thermostatic expansion valve, how it works, and its benefits. If you want to learn more about how a TXV can make your air conditioning unit work efficiently, contact Summit Heating & AC, your go-to air conditioning contractor.

Apart from cooling services, we also offer a wide array of heating and plumbing services to the residents of Denver and the surrounding areas. Contact us today if you have any other questions about the thermostatic expansion valve or would like a cooling system with a TXV installed at your residence.

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