How to Install an Air Compressor Check Valve

An air compressor check valve is a one-way or a non-return valve. This means that if a check valve is installed in line, it will not permit the air to flow back from the air-receiver tank to the compressor. The check valve performs this function and allows the air to move from compressor to air tank only. The compressed air discharged from the compressor flows through the high-pressure pipe fittings to the air receiver through the check valve and gets stored there. As the air gets consumed, more air from the compressor flows into the tank. The accumulated air in the tank can be used any time for running the tools and equipment and gets replenished. You can easily locate the check valve in the compressed air line.

Materials and Tools

  • Check valve
  • Flashlight
  • Adjustable pipe wrench
  • Teflon tape
  • Socket spanner

Step 1- Buying a Check Valve

Refer to the manufacturer's maintenance manual. Get the details and part number of the check valve required for your compressor and purchase it from the manufacturer or supplier.

Step 2- Getting Prepared

Stop the compressor. Close the air outlet valve(s).Switch off the power supply and disconnect the compressor from the mains. Other people should be cautioned that it is to be kept switched off. Depressurize the compressor. Turn off and depressurize the air net, which is connected to compressor. Disconnect the compressor by unscrewing it from the air net.

 Step 3- Locating the Outlet

Search at the top of the compressor cylinder head where both its inlet and outlet valve manifolds are mounted. The inlet manifold piping is fitted with a filter connected to it and there is no filter at outlet piping. Move along the discharge piping towards the air receiver tank. You can use a flashlight if needed.

Step 4- Finding the Check Valve

Locate the compressor check valve near its head where the discharge pipe line is connected to it. There is small unloading tube coming out from the check valve that can also help in identifying it. The compressed air discharge pipes go from the compressor to its check valve before going to the pressure tank, irrespective of the size or capacity of the compressor.

Step 5- Dismounting Check Valve

Read the maintenance manual supplied with the compressor. All makes and models will have different types and sizes of the check valves.  Use the tools and instructions given in the manual to open the housing and for removing the check valve from the outlet. Clean the outlet. Dirt, carbon, condensate formation and oxidation impact the proper operation of the check valve.

Step 6- Installing Check Valve

Follow the instructions given in the maintenance manual for installing the check valve, as you did while removing it. Install the check valve. Fix the housing. Put back and reset all the connection of air line.

Connect back the compressor power supply and open the outlet valve to receiver. Compressor is ready to work.