I'll start out by saying, you need to have your irrigation system professionally winterized to avoid freeze damage. In addition to a more thorough winterization and system check, professional winterization can also help you keep your warranties intact - especially important for new systems. However, in the Atlanta area, we know that winter is not severe and many homeowners will skip the professional irrigation winterization. If you fall into this category, please do us a favor, and at least take the following precautions yourself:
Tips for Winterizing Your Sprinkler System
Turn off the water. I realize this seems obvious, but the trick is to do it before the first freeze.
Drain water from the pipes. Open all your valves and your pressure vacuum breaker and let all the water drain out. Ideally, you would use a method to evacuate the water, such as an air compressor.
Turn off the controller.
Drain and insulate the backflow preventer. Your backflow preventer should be drained and insulated. You can buy insulation from your local hardware. Since this device is above ground, it is subject to freeze easily.
Insulate valves. Use pine straw or insulation tape to protect your valves from freeze damage all winter long.
Again, we stress the importance of having a professional winterize your system. Not only will your system be better protected, but at Conserva, we also assess your system for issues. We can provide you with a list of needed repairs so you can prepare all winter for spring repairs and adjustments that will help you save money as soon as you turn your system on in the spring.
However, if you have to do it yourself, make sure you do it right!