How to Winterize a Sprinkler System

Winterizing your irrigation system will keep it running better and longer. Take these steps to prepare your sprinklers for the cold season. Your yard will thank you when you can still water the lawn next spring.

Compressor Set-Up

With a basic quick-connect coupling, you can use your air compressor to clear water from your sprinkler system for the winter. Just be aware that even the largest home compressor isn’t powerful enough to blow out the entire system at once. But you can probably blow it out zone by zone.

If you’re into number crunching and you have the original irrigation layout showing the gallons per minute (GPM) of each sprinkler head, just divide the total GPM of each zone by 7.5. That’ll give you the cubic feet per minute (CFM) you need to blow it out. Otherwise, just rent a 10-CFM compressor and hose from your local tool rental center.

Set the compressor air pressure regulator to a maximum of 80 psi for rigid PVC pipe systems, or 50 psi for flexible black polyethylene pipe. Then turn off the water supply and set the sprinkler system timer to open just one zone. Next, open the manual drain valve at the end of that zone (if equipped).