Sprinkler System Freeze Protection

By Joe DiBlasi


Here in the Metro Denver area our sprinkler systems are subjected to freeze damage every winter, spring and fall. Your system needs to be professionally serviced for the winter season. At JKJ Lawn Sprinkler we provide this service by blowing out all the water that is in the system with an air compressor that develops the correct volume of air. We then set all valves, drains and your controller correctly for the winter. If these steps are not taken costly damage may result. This service is performed in October/November.

We do have early freezes in the fall and late freezes in the spring when sprinkler systems are still operational. There are steps you can take to protect your system if this happens:

Step #1- Shut-off - Close the sprinkler system shutoff valve, this valve is usually located in your basement or crawl space. Some systems have outdoor shut off valves in the ground so you want to be familiar with their location. Turn off the sprinkler controller or timer.

Step #2- Insulate - Cover the Backflow Prevention device, this is the part of your system that is usually damaged by freezing temps. There are several styles, but most have a “bell’ on top, and they are usually about a foot of the ground, up against your house. Cover the entire device and piping around it with blankets, insulation, etc. then cover that insulation with a black trash bag securing it with duct tape. JKJ also can provide an attractive insulating cover that can be used year after year.

Steps #1 and #2 will provide the minimum protection against freeze damage. This is usually sufficient for a freeze period lasting 12 hrs. or less. If a freeze period is expected to last more than 12 hrs. you can take an additional step toward protecting your backflow protection device.

Step #3- Drain - To drain the back flow prevention device, complete step #1. On the backflow prevention device there are several drains, these need to be opened completely. Most systems have a valve box in the ground close to the backflow prevention device, inside there is usually a drain, open this one as well. These drains usually require a flat screwdriver to operate. Now you need to open the drain on the system shut-off valve in the basement or crawl space. You will want to have a small bucket to catch the water that comes out. After draining is complete leave drain partially open, with bucket underneath. Now go back to the backflow prevention device and leave all valves halfway open, including the drains you opened completely.

Now complete Step #2- Insulate. Once you have completed these steps your system is well protected from freeze damage.

For more information on blowing out your sprinkler system this fall, or any other sprinkler needs, contact JKJ Lawn Sprinkler today!