Pond Boss Forums AERATION Systems questions Diffuser setup

Check valves on diffusers are important to reduce chances of forming an ice plug in the airline and to reduce undue stress on the compressor at start-up especially if the system is cycled on-off. Some professional systems have two check valves; one on each diffuser and one at the compressor. If there is no check valve, water fills the airline when the compressor is off. At start up, the compressor builds extra high operating pressure (sometimes 3X normal) to push the water out of the airline. When air reaches the diffuser the pressure drops back to the normal operating psi. Excess pressure adds stress to the mechanics and over time shortens the life of the compressor.
A 3rd reason for a check valve is to reduce the chance of water draining or getting sucked back into the compressor during any off period. Water can drain back into the compressor for various reasons. Water in the compressor will damage or ruin the compressor. Water and excessive heat are the two main enemies of air compressors.