How to Blow Out Sprinkler System

If you live in the Alpine heights or any other region where it gets viciously cold in the winter months, chances are you’ve had your fair share of sprinkler systems bursting at the seams. What gives? What happens to sprinkler systems that make them break when frozen over?

Why your sprinkler system breaks

Water, when frozen, has the tendency to expand. In the winter months, if it becomes cold enough to freeze out water, the water in your sprinkler system might freeze over while they’re inside the sprinkler heads, the pipes, and the irrigation valves.

When that happens, the water will expand and cause your sprinkler system to burst, leaving you unable to use it when the spring months rollover.

What should I do?

Winterizing your sprinkler system means adapting or preparing something for use in cold weather. It’s precisely what you should do to your sprinkler system before the winter months arrive, to save yourself the pain and expenses of having to look for replacement parts.

There are three methods that you, or your hired professional, can use to keep your irrigation system safe during the winter:

  • Manual drain method
  • Automatic drain valve system
  • Air blowout practice

The latter choice, air blowout practice, is the most applicable to most sprinkler systems and one you can do on your own. If you’re not confident with your skills, you can hire a contractor to do the job for you. But in any case, get to know these following steps so you can either do the job safely and correctly or be at ease knowing exactly what your contractor will do:

Shutting off the water

Since what you will be doing is essentially draining your sprinkler system of water, this step is crucial. Find the master shut off valve in your house and turn off the water.

Drain the water

Even though you’ve shut off the mainline of water going through your sprinkler system, there will still be water remaining inside. You will have to manually drain the water from the system, so open the hose bib and catch the water with a bucket.

Be prepared for a mess as the pressure from the pipes may make the water spurt uncontrollably.

Use the compressor

You may have a compressor on hand, but the little ones available at the shop tend to be too weak to get the job done. Your contractor may have one to use, but if you’re DIY-ing, you can opt to rent a good-quality powerful compressor from a nearby equipment rental yard.

Attach the compressor to the hose bib and let it do its job of emptying the pipes.

Let your sprinklers lose

To be able to check and see if there is any water remaining in the pipes, or to help get rid of the last drops still nestled inside the system, turn your sprinklers on. You’ll know that the job is done once the water coming out of it has turned from mist to air.

Repeat these steps until all the zones for your sprinkler system are set and ready to brave the harshest winters.