Sprinkler System Winterization

Just before the first Nebraska freeze, it becomes necessary to winterize outdoor sprinkler systems. For those who live in colder climates, like Omaha, where the frost level penetrates to the depth of the irrigation system piping, winterization is very important. Any water left in the sprinkler system can freeze which can result in the excessive expansion and bursting of the polyethylene or PVC piping. Living in Omaha, Nebraska, we all know that weather can change drastically, which is why it’s important to drain the system prior to the first freeze. At Above and Beyond Complete Ground Maintenance, we recommend doing it early October.

Draining your system properly is the most important thing you can do to protect it, which is why you should hire a professional Omaha landscape company, like Above and Beyond Complete Grounds Maintenance. Most spring repairs occur because systems still had water in them when freezing temperatures hit. Knowing how to drain your system is very useful, allowing you to water during the warm spring and fall days while protecting it from below freezing temperatures at night. This type of weather is really common in the Nebraska area. Rainbird.com has many tips on how to protect your system from winter damage. You can winterize your system 3 different ways:

The Manual Drain Method:

1. Turn off the water supply. This is typically found in the basement or a utility room.
2. Open the manual drain valves and allow the water to drain. Warning: Sometimes the water is still under a lot of pressure and comes out quickly at first. You may get wet! Bring a bucket.
3. Open the drain cap to allow the remaining water to drain.
4. Open the test cocks.
5. Make sure all of the water is drained from the piping and sprinkler.
6. Close the manual drain valves.

The Automatic Drain Method:

Follow all of the same steps as above. This method is used with a system that has drain valves that are low in the irrigation pipes. The only difference is that in Step 2, the zones are activated and the pressure is relieved. The water then drains automatically rather than manually.

The Blow-Out Method:

The most involved method of the three, but also said to be the best. This can be quite a bit trickier to do yourself, so we suggest professional help from Above and Beyond Complete Grounds Maintenance if you are at all unsure of how to do this method. An air compressor is also needed for this method.

1. Attach the compressor to the mainline in front of the backflow device.
2. Open the test cocks.
3. Turn off the water supply and open the drain on the supply line. Allow water to drain.
4. Close the drain.
5. Connect the air line.
6. Attach the hose of the air compressor.
7. Find the zone that is the longest distance from the compressor and turn it on.
8. Gradually open the air on the compressor so that air slowly enters the sprinkler system. Keep the pressure at 50 PSI.
9. Add enough air to seal the sprinkler heads, but don’t go over 80 PSI.
10. Working your way from the farthest away to closer to the compressor, activate each zone until no more water exits each zone. Usually spend about 2-3 minutes per zone.
11. Turn off and disconnect the air compressor.
12. On the backflow device, open and close the ball valves about five times each. Leave the valves open at a 45 degree angle. This prevents the valves from cracking if they freeze.
13. The test cocks should remain open.

And you’re done, at least until next year!

The best thing for your system is to have it winterized or blown out by a professional company, like Above and Beyond Complete Grounds Maintenance. Most residential air compressors aren’t strong enough to properly blow out the lines. A contractor will use a commercial sized compressor hooked up to the drain or the backflow preventer to push water out of the system.

The Do NOTS of “BLOW~OUT” Winterization

1. Do not allow the air pressure to exceed 80 PSI for systems with PVC piping and 50 PSI for systems with polyethylene piping.
2. Do not stand over component parts while the system is pressurized with air.
3. Do not leave the air compressor unattended.
4. Do not blow the system out through a pump. First blow out the system, then drain the pump.
5. Do not leave the manual drain valves open after the blow out.
6. Do not leave the indoor drain open during the blow out.