How to winterize irrigation system?

How to winterize irrigation system?

How to winterize irrigation system?

Its that time of year to get the irrigation system winterized!

Winterizing your irrigation system is crucial to protecting your landscape investment.

Having a professional winterize your irrigation system can cost anywhere from $60-$150.

But here's the deal, if your handy, it's not difficult to do on your own!

All you need is a compressor, and this guide to winterize your irrigation system.

Choosing the Right Compressor

If you do not have a compressor or have a compressor that is strong enough for your needs, you can rent one from a nearby rental store.

Be Aware, you will need a compressor strong enough to do the job.  You need one with enough Cubic Feet per Minute or CFM to push the water out of your irrigation pipes. Typically you will need at least 9 CFM to adequately flush the water from your sprinkler system. 

What is so important about the CFM? 

Using a low CFM compressor means pumping the water out of your irrigation lines will take longer, as a low CFM compressor pressurizes much slower.

This means that you will spend a long time waiting for the pressure to build up in the line. Most people don't know this but, it can be the difference between spending 15 minutes to drain the system, or spending the entire weekend with a weaker compressor.

Pro Tip!
Some people believe you can "drain" your system, however, as professional in the industry for 15 years, I have repaired dozens of systems that were improperly winterized by the draining method.

Pool Rental Costs with Neighbors

One money-saving idea would be to rent a compressor and split the costs with your neighbors.  Rental fees will be $50-$75 for one day, but if you split that cost with five of your neighbors, you are looking at only $10 - $15 each.

And hey if you want to start an irrigation winterization service, maybe you can invest in a compressor. You can also use this awesome guide to start your lawn care business.

Step One: Connect the Compressor

The first step is to shut the water supply off at the main sprinkler shut off valve. This is typically located near the water meter or near the foundation of your home. Then you can connect the compressor to the irrigation system at the "back-flow preventer" or at the "winterization fitting". Which is typically located at the water meter, or near the back-flow.

NEVER EXCEED 80 PSI!!! Be sure to set the proper PSI and that it remains less than 50 PSI for Poly Pipe systems and 80 PSI for PVC systems.

Step Two: Activate The Irrigation System

Then you will want to cycle through each zone one at a time. Activate the first zone on the control panel, and then start the compressor, complete Step 3 and repeat in the next zone.

Step Three: Cycle Through the Zones

Cycle through all of the zones, advancing to each zone after all of the water is pushed through the irrigation heads, and all you see is misty air coming through them.

Step Four: Open the Test Ports

After you have cleared all of the zones of water, then its time to open up the test ports on the back-flow with a regular screwdriver, flushing the water out of the back-flow.

Step Five: Wrap it Up

Once the water has been pumped from the irrigation lines, stop the compressor, de-pressurize the tank, and disconnect the hose.

Now its time to loosen the bolts on the lower of the backflow and drain the water out of the . 

Finally, open up all the plugs on the back-flow and leave them loose. Turn the control to off, and you are all set!!!

Frequently Asked Questions

What happens if the irrigation system freezes?

If an irrigation system freezes, it can lead to burst pipes, damaged valves, and cracked sprinkler heads, requiring costly repairs.

How much does it cost to winterize an irrigation system

Typically ranges from $50 to $150, depending on the system size and service provider.

When should you winterize an irrigation system?

  • Before the first hard freeze in your area.
  • Check your local weather forecast for predictions.

When should irrigation systems be blown out?

Irrigation systems should be blown out (clearing water from lines) in late fall before ground freezes.

Optimal Timing for Blowing Out Irrigation Systems: 

  • Late fall, before ground freezes
  • After the system has been shut off for the season
  • When nighttime temperatures consistently drop below freezing
  • Before any hard freezes occur
  • Typically in October or November for most regions.

What type of compressor is needed to winterize an irrigation system?

You'll need a compressor with a minimum of 9 Cubic Feet per Minute (CFM) capacity to adequately flush the water from your sprinkler system. A low CFM compressor will take longer and may not be as effective.

Where Can I Find a Professional for Winterizing My Irrigation System?

If you prefer professional help, platforms like GreenPal offer a network of lawn care professionals across many neighborhoods, ensuring reliable and efficient winterization services.


Now, I would not recommend you perform this service yourself unless you would consider yourself "handy" and have experience with similar home service routines. Otherwise, if you have serviced your own pool, car, air conditioner units or like tasks, then this something you can totally do.  But be advised, if this is not properly executed then you will sustain hundreds if not thousands of dollars in damage to your system.

In Conclusion

Winterizing your irrigation system is essential for protecting your landscape investment from freezing temperatures. You can do it yourself with a compressor or hire a professional for $60-$150. The compressor should have at least 9 CFM to flush the water effectively. 

Follow the steps: shut off the water supply, connect the compressor, cycle through zones, open test ports, and drain the system. Never exceed 80 PSI when using the compressor. Consider splitting compressor rental costs with neighbors

That being said, if you don't feel safe doing it yourself, and need to hire a professional try  GreenPal. Our network of lawn care professionals is available to meet your needs, in many neighborhoods across the country.

If you learned something about irrigation winterization, share this article and the infographic below with your friends and family!

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