Air compressor check valves are called non-passing or one-way valves. If there’s something in the line where a check valve is installed, it only flows in one direction. Many air compressors have issues with their check valves over time, and it’s important to know what they are and how they promote or impede air flow.
Every air compressor has one of these check valves, and they’re important to help them run correctly. Your rotary screw compressor has one, and so does a reciprocating piston compressor.
Often, reciprocating piston compressors have more than one for the compressor tank. The goal is for the compressed air to go through the valve with no way of going back out and is crucial for a compressed air tank.
Overall, compressed air passes through the rotary screw compressors (and others) and often gets damaged. If you hear air leaking or something’s blocking airflow, it’s best to get a new one. Here are the best options available:
Best Check Valves for a Compressed Air System
With this list of check valves, you’re sure to find something for your air receiver tank. It should hold air pressure without any leaking air. Let’s check out the top options:
Hromee Air Compressor Check Valve Kit
When the goal is to have the right amount of compressed air with no leaking, it might be time to consider the Hromee brand. Its check valve kit can prevent backflow in the piping system. Overall, the pressure going through the pipe opens the valve, and reverse flow shuts it off. That way, it automatically shuts off when the pressure decreases.
Each check valve is brass, and there are two unloader fittings (push to fit and barbed) to fit a 1/4-inch nylon tubing. Plus, it features a one-piece body and stainless steel springs. You also get glass-filled poppets for reliability and durability. With that, you’re allowed to disassemble it for repairs or cleaning.
This product has a maximum airflow of 20 SCFM and a pressure of 450 PSI.
Overall, the valves are 1/2-inch, but there’s a 1/8-inch side port for pressure switch applications.
Hyuduo 3-port Air Compressor Check Valve
With the Hyuduo check valve, you get three connectors, all of which are male. These threaded connectors can be used for piston pumps, pressure tanks, and pipe connections.
You’re sure to appreciate the brass body and disc, both of which are heavy-duty cast. That means they are lead-free, corrosion-resistant, and dezincification-resistant. Plus, the threaded ends comply with the ANSI.B2.1 regulations and conform to the NSF/ANSI-61/372 specifications.
Steuby In-tank Check Valve
Choosing the Steuby brand means that you get a check valve that’s compatible with 3/8-inch compressors and 1/2-inch NPT. It also contains an unloader port on the side, featuring 1/8-inch female threads.
However, some compressors don’t need that, so you can always plug it up if necessary.
Types of Check Valves
It’s crucial to understand which check valves are needed for the various air compressors. For example, an inlet check valve is different than an in-tank one. Let’s learn the different types:
In-tank Check Valve
In-tank check valves are designed to prevent backflow through your compressor pump. They’re fitted right into the tank to seal the compressed air within.
If there wasn’t a compressor tank check valve, the airflow could bleed from the piston when the compressed air stopped flowing, and you opened the unloader valve. Overall, the purpose of the compressor tank check valve is to keep the air in the tank for air tools.
When compressor components operate normally, the pressure switch senses the cut-in pressure. That means the pressure switch closes and turns on the motor. At the same time, this pressure switch closes the unloader valves. Check valves are opened when compressed air goes above cracking pressure. Then, when the air in the tank reaches the right pressure, the pressure switch reopens, shuts the motor off, and opens the unloader valve, repeating the process as needed.
In-line Check Valve
In-line check valves are found in the air pipe or hose. It doesn’t seal the air tank volume but can prevent back airflow like one.
Overall, the air flows from the tank into the air line and check valve. Since it’s a one-way valve, the air in the line can only get out from the air tool.
Conclusion
It’s nearly impossible to determine which of the check valves listed earlier are the “best” because each one is a different size. The beauty is that you can find air compressor check valves to handle compressed air, regardless of what machine you have.
Now that you understand a bit more about check valves and why they’re used, you can measure your system to find the best product for your air tank.
You also have a side-unloader port, which is 1/8-inch with female threads. This measures 10/32 inches in diameter. The port is primarily used as an unloader line, and some compressors don’t require this. If that’s the case for you, just plug that port to prevent air from escaping.
