The air conditioning systems in your home rely on a complex series of components such as electronic expansion valve to function. Perhaps you’ve heard about it, or maybe this is the first time you’re learning about its existence.
Either way, it’s a crucial piece of machinery in your AC or fridge. But what is it, and how does it work? Keep reading to find out.
What is an electronic expansion valve?
An expansion valve is a measuring device that regulates the flow of refrigerant reaching the evaporator in an air conditioning or refrigeration system. It helps maintain optimal operating conditions by modulating the flow based on the system’s needs. Simply put, it helps keep things running smoothly.
How Do Electronic Expansion Valves Work?
The HVAC system employs the electronic expansion valve between the evaporator and the condenser. Its primary purpose is to meter the correct amount of refrigerant from the condenser. It holds back the high pressure and decides how much refrigerant goes into the evaporator.
As the liquid bursts through the small gap in the valve, it experiences a drastic pressure drop. That causes it to expand rapidly and partially evaporate into a gas. It then gets sprayed into the evaporator coils, where it can absorb heat from the surrounding air.
This seme liquid refrigerant creates an increased surface area for heat transfer, taking on more heat energy from the surroundings in the process, which results in greater cooling capacity. If the valve is not working correctly or the refrigerant flows too little, evaporation will occur quickly, leading to rising temperatures. That means the system will ultimately fail due to overheating. Moreover, it could lead to compressor damage.
On the other hand, if it’s too much, the pressure in the evaporator will decrease. That will make the system less effective and use more energy than necessary. In some cases, it could also lead to freezing the evaporator coils.
For an expansion valve to function correctly, it needs an external controller that monitors conditions in the system and sends signals to the valve. That’s where the “electronic” part comes in. Electronic expansion valves get controlled by an electronic control unit (ECU).
The ECU monitors the system’s conditions and adjusts the expansion valve as needed. It helps ensure that the system is operating at peak efficiency throughout.
Advantages of Electronic expansion valve
Electronic expansion valves offer several benefits over traditional mechanical expansion valves. First, they are up-to-date with the latest technology. That means they are more accurate than their mechanical counterparts. Other advantages include:
Efficiency
One of the most significant advantages of electronic expansion valves is that they are much more efficient than their mechanical counterparts. That’s because they can modulate refrigerant flow electronically rather than mechanically. As a result, less power wastage leads to lower operating costs.
Highly Reliable
Another advantage of electronic expansion valves is that they offer more precise control than mechanical expansion valves. That means they are less likely to experience problems and can provide reliable performance for a more extended period.
Better Temperature Control
Electronic expansion valves offer better temperature control than mechanical expansion valves. That’s because they inject the right amount of refrigerant into the evaporator, which helps maintain optimal operating conditions. They also respond fast and accurately to any system load change. That leads to better cooling and more comfortable indoor temperatures.
Improved Durability
Electronic expansion valves are also more durable than mechanical expansion valves. That’s because they have fewer moving parts, so there are fewer opportunities for leakages or other things that can go wrong. They will service your system for longer with fewer problems.
Easy to install
Finally, electronic expansion valves are also easier to install than mechanical ones. That’s because they do not require any special tools for installation. While you will still need the input of a professional to install them properly, the process is generally much simpler and quicker than it is for a mechanical valve.
If you want to DIY, you will need a basic understanding of how the system works and the ability to follow instructions. However, to avoid damaging any internal components of AC, it is always best to consult a professional before attempting any repairs or replacements.
Types of Electronic expansion valve
While there are at least six types of expansion valves, there are two main types of electronic expansion valves. They include:
- Thermostatic expansion valve
- Electronic expansion valve
Electronic expansion valve vs thermostatic expansion valve
The most significant difference between these two expansion valves is how they modulate the refrigerant flow. A thermostatic expansion valve uses a sensing bulb filled with refrigerant to modulate the refrigerant flow. On the other hand, an electronic expansion valve uses an electronic control unit (ECU).
The TXVs are the most common type of expansion valve. They use temperature-sensitive elements to control the flow of refrigerants.
The valves have main components, including a removable cap, Power Head, Capillary tube, and Sensing Bulb. When the system’s temperature rises, the element expands, creating pressure that travels through a tiny capillary in the power head. In turn, the power head actuates a valve that opens or closes to modulate the refrigerant flow.
The advantage of this type of expansion valve is that it can handle large refrigerant loads without any issues.
The electronic expansion valves are the newest type of expansion valve on the market. They use an electrically-actuated valve to control the flow of refrigerants. The electronic control unit (ECU) constantly monitors the system’s conditions and adjusts the expansion valve as needed. It also has a shape memory element (FGL) that helps the valve open and close as needed.
The main advantage of this type of expansion valve is that it can provide more precise control than a TXV. That’s because the ECU can make real-time adjustments to the expansion valve based on the system’s conditions.
Like the TXV, this one also has a higher maximum operating pressure and can handle large loads without problems. The only disadvantage is that it is more expensive than the TXV.
While both expansion valves offer benefits, electronic expansion valves provide more advantages than thermostatic expansion valves. They are more efficient, reliable, and have better temperature control. They are also easier to install and more durable.
Next time your HVAC system breaks down, the expansion valve could be the culprit. But don’t worry, it’s not the end of the world. Consult with a professional for inspections. If it’s the course of the problem, the technician will recommend the best expansion valve for your system.
