Freezing temperatures can damage sprinkler components & backflow devices, making October the ideal time to blowout your system.
If connected to domestic/city water, turn off the main valve, connect a compressor to the backflow or blowout port, cycle through each station until heads are misting, open the drain valve, & leave the backflow handles & test cocks set to 45-degree angles. This allows any remaining water to drain out.
If connected to pressurized irrigation, especially in an HOA or shared system, close the main valve, connect a compressor to the blow out port, & blow out the lines.
TIPS:
Don’t over do it on rotor heads. Water lubricates the gears so if they’re rotating without water for long, friction can cause damage to the gears. You needn’t blow out every drop of water. Just get a mist & you’re good to go.
If you have cross-tops on your main & drain, don’t over tighten them. They can break easily & you’ll be digging a deep hole to fix them.
On a pressurized system, if you blow out before the system that feeds yours is winterized, some water could remained trapped in the valve & main lines before it. This “usually” doesn’t create a problem but can.
