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:
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.
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.
Overall, the threaded connection is designed to be tighter and provide an easier installation. With that, you get a good performance because it features corrosion resistance, compressive strength, and reliability.
Another three-way check valve that made the list is from FTVOGUE. This is a great replacement valve for broken or old ones on the air compressor. Plus, it features thread-connecting ends to make it convenient to install.
The three male connectors are designed for piston pumps, pressure tanks, and tube connections.
You’re sure to appreciate the removable design of the valve. That way, it’s easy to clean the internal components, which makes it healthier to use. With that, it’s long-lasting and durable.
Overall, you don’t need tools to install it. Plus, there are no raised corners or points, meaning it doesn’t hurt your hand when you put it on.
The Conrador brand is a check valve unloader and is suitable for electric- or gas-powered compressors. With it, you can adjust the pressure to 30 or 40 PSI.
You’re sure to appreciate that there’s a 1/2-inch FPT inlet and a 1/2-inch pipe thread outlet (male connection). It also features a muffler or silencer with a 30 SCFM rating.
On one side, there’s a 1/8-inch port for cables or throttle control valves. This makes it suitable for various applications.
When you choose the Joywayus brand, you get a three-way check valve with male thread sizes of 1/8, 3/8, and 1/2 inches. It’s made of high-strength brass, so it’s good for corrosion resistance.
With that, the three thread connectors are designed for use with pressure tanks, tube connections, and piston pumps.
You’re sure to appreciate this replacement for a broken or old check valve. Though it’s easy to install, it’s best to ensure that the compressor is off and there’s no pressure inside before doing anything.
If you need a new check valve for the tank, Control Devices has you covered. It’s a poppet-style in-line valve, and it installs within the discharge line of your compressor. In a sense, it’s great for situations where an in-tank valve can’t fit.
This valve is made of brass, which is often seen as a better choice than steel because it’s more corrosion-resistant. The inner PTFE poppet spring is made using stainless steel.
On one end, you have a compression connection, but on the other, there are female NPT threads to connect to a male-threaded pipe. This is often seen as more versatile than male threads, but it also depends on your situation.
The maximum pressure rating of this valve is 450 PSI with a working temperature of up to 400 degrees Fahrenheit.
Those who need an in-line check valve for their air compressor are sure to appreciate the Conrader brand. It features a flow capacity of 60SCFM at 100 PSI. However, the maximum operating pressure is 250 PSI. This brand also features an operating temperature of anywhere from -65 degrees Fahrenheit to 450 degrees Fahrenheit.
However, you must make sure that your compressor has a 3/4-inch NPT, which measures 1.05 on your tape measure.
Overall, this is a great choice because it’s made of brass and has a reinforced PTFE seal.
The CDI brand also carries a check valve for inside the tank. The outlet threads are male and measure 1 9/32-inches in diameter. They are what screws into the 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.
With the Midline Valve brand, you can choose a single check valve or a five-pack to save money. It features a tilting disc, which blocks the reverse flow in your piping system.
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.
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.
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.