If you live in a freezing climate, it is recommended that you winterize your sprinkler system to avoid
potential freeze damage to your valves, sprinkler lines, and heads. To properly winterize your system, it is recommended that you use one or more of the following methods: Automatic Drain, Manual drain, Blowout with compressed air, or a combination of methods.
AUTO DRAINS #
Do not install auto-drains on the sprinkler mainline.
Auto-drains will not remove all of the water captured in the valves. Loosen the bleed screw, loosen the solenoid on automatic valve(s), or blow out with compressed air to winterize valves.
Auto drains should be installed on the downstream (outlet) side of the valve, NOT on the mainline. Automatic drains close when water pressure is applied (when your water is on) and open when the water is off, thus allowing the water in the line to drain. They should be installed at the low point(s) of each zone in order to drain any sitting water in the lines. In most cases, two auto drains per zone are sufficient. You may have zones that require more, or less, than two.
MANUAL DRAIN VALVES #
Manual drain valves should be installed at the lowest point of the sprinkler mainline, as close to your main shut-off as possible. Multiple manual drains should be used if there are various low points in your system.
Valves that may be used as manual drains include Gate Valves, Ball Valves, or Stop and Waste Valves.
Manually draining your system will not remove all of the water captured in the valves. Loosen bleed screw or solenoid on automatic valve(s) or blow-out with compressed air to winterize valves.
You should allow for easy access to the manual drains in your system. Cover with a 6” or 10” round valve box and fill the base with gravel for drainage. Mark the location of all manual drains installed in the system for future reference.
BLOW-OUT WITH COMPRESSED AIR #
Use caution when blowing out the system. Excessive pressure can damage system components or cause physical injury. Air pressure must not exceed 50 pounds per square inch (psi).
Caution! Wear proper eye protection!
Using compressed air, water can be forced out of all of the irrigation system components. You will need a compressor capable of providing 10 to 25 cubic feet per minute (CFM) of air volume. Air pressure must not exceed 50 pounds per square inch (psi). Air volume should be high and air pressure low; this combination will prevent damage that may occur during winterization.
DO NOT use a high-pressure, low-volume compressor. Use a pressure regulating valve to avoid over-pressurization of your system. It is recommended you hire a contractor to perform this procedure if you do not have a compressor that meets these specifications.
Blow-out procedure: #
Never run compressed air through your system without opening at least one sprinkler control valve as air generates higher stresses than water.
Note: Only operate one zone at a time.
- Close mainline sprinkler shutoff valve.
- Relieve mainline pressure by manually opening one of your zone valves.
- Attach the compressor hose to the blow-out adapter.
- Set the pressure regulator on the compressor to 50 psi.
- Turn on the zone valve you wish to blow-out. This can be done with the controller (see your controller instructions for manual operation), or by manually operating the valve with the solenoid, bleed screw, or manual lever.
- Turn on your compressor and slowly increase the pressure until your heads pop up. Water has been properly purged from the system when a fine mist (or air only) comes out of the heads. Do not run compressed air through a zone for more than 2 minutes.
- Perform this operation for all zones in your irrigation system.
- Repeat and run a second cycle of air through each zone to ensure that all water has been evacuated.