Air valves, also referred to as pneumatic check valves
, are special types of valves designed to allow air to move from one side to another but preventing it from moving in the opposite direction. This implies that once air passes at a specific pressure, the valve makes it easy to maintain that pressure. This is why the air valves are very common in applications such as scroll compressors.In most cases, individual compressors are fitted with multiple air valves. You can even get up to five valves attached to one compressor. These air valves are used in multiples because some applications might require being constantly pressurized while others do not. Besides, the valves ensure the air that was released to run various parts does not get back to the compressor.While air valves can take varying forms, the operation principle is similar. They have a ball and a spring. The spring is relatively weak so that the pressurized air from the compressor easily pushes its way through. But as the air tries to push back, it pushes the spring and the ball back to the entry point. The effect is the sealing of the opening and preventing backflow.