If you maintain sprinkler systems in cold winter areas, you’re bound to receive several questions about blowing out sprinkler systems. During every season, we are asked the same question by homeowners and professionals alike: “How do I connect my compressor to the backflow?” While this is a simple enough question, the answer is a little more involved.

Most backflow prevention devices are truly not intended to have air forced through them, especially not through the tiny test ports most people try to connect to their compressors. The backflow preventer, or commonly referred to as “backflow,” is designed to keep dirty water and contaminants from re-entering the fresh water supply—and that’s it.

A standard sprinkler winterization will require between 80 to 100 cubic feet of air per minute to properly evacuate excess water from the system. When connecting to a test port on the backflow, you are trying to push all that air through a hole smaller than a quarter inch! Could you imagine how long it would take to fill your car’s gas tank with a quarter inch nozzle?

In addition to its inefficiency, the air pushing through that tiny opening can heat up the internal components of the backflow and cause damage, which can lead to expensive repairs that would otherwise not be required.

Luckily, there’s a much better way.

Add a Blowout Port After the Backflow

Adding a blowout port can be done with a few different methods: by using a simple copper tee with a removable PVC plug, by installing a copper tee with a permanent hose bib or even by using a quick-coupling valve installed below ground. Any of these great options will create an easily accessible, properly sized connection point to which you can tie your compressor.

By closing the downstream ball valve of your backflow, it will also be completely isolated from the sensitive internals that were at risk of being damaged before.

For much less than the cost of a backflow repair kit, you can prevent blowout damage and increase blowout speeds for the life of the backflow preventer—a win-win situation for you and your customer!

Check out the video below for more tips and how-tos regarding winterized sprinkler systems, and keep your system running smoothly at all times of the year.

Have you tried this method before? What other methods work best for you? Share with us in the comments below.