Winterizing Your Sprinkler System

Last Updated on Thursday, 13 May 2010 19:44 Thursday, 13 May 2010 00:00

Articles - Irrigation Systems

Sprinkler pipes, zone valves, and backflow preventer's will freeze and eventually break when temperatures become 32 degrees Fahrenheit and lower. Immediate damage can occur to exposed pipes and sprinkler parts with the first winter freeze if all the water has not been removed. Further damage can result as freezing temperatures and wind chill conditions cause the soil to freeze at the same depth as the underground pipes. In many cases, homeowners are not aware that their pipes have been damaged until they begin watering in the spring and discover leaks in their yards!

Draining Your Sprinkler System

Some systems are self draining or manual draining. If you not sure on what type of system you have, you should have it blown out with air from an air compressor.

How to Connect the Air Compressor

Most sprinkler companies hook the compressor up directly to the backflow device although it is not recommended. This is because there is a threaded tap that you can attach to. There should be a tap supplied on the pipe past the backflow. If you do not have one, you should plan on having one installed.

Backflow Preventer

Backflow systems are mandated by most code for protection on all sprinkler systems. They serve as a barrier to prevent contaminated water from the sprinkler system from entering the domestic water supply. Backflow systems may be located above or below ground level and like sprinkler pipes, must be properly winterized for protection from freezing and breaking.

Air Compressor Size

The rule of thumb is that the compressor should be large enough to raise the heads completely above ground. Continue with the pressurized air until all the water is removed and only air is dispersing from all the heads. Do one zone at a time. You do not have to worry about damage to your system as long as the air pressure does not exceed your water pressure; 50 to 80 PSI is recommended. The blow out method utilizes an air compressor with a Cubic Foot per Minute (CFM) rating of 80-100 for any mainline of 2" or less. These types of compressors can be rented at your local equipment rental store. The compressor is attached to the mainline via a quick coupler, hose bib or other type connection, which is located after the backflow device.

Thaw a Frozen Sprinkler System

If your system does wind up freezing, here are a few things you can do. Shut the water off to the system, open the drain valves and cover your backflow preventer with insulation if you expect the temperature to suddenly drop (this is a temporary solution). If your pipes or backflow has frozen water in it, you can thaw it out by wrapping it in rags and pour boiling water over it. This works well on plastic pipes. You can use a torch on brass pipes but be careful of starting a fire on wood siding and never use a torch on plastic pipes or components.

< Prev