Should you blow out your system or simply drain it? In areas with a frost depth of 18" or less, proper draining is often sufficient. Blowing out adds an extra layer of protection but may not be necessary for all residential systems. For commercial systems, blowing out is recommended. If it's standard practice in your area, consider professional winterization.
Important Safety Information: Do not use a standard compressor with a storage tank to blow out your sprinkler system. This poses a significant risk of damaging your system and can be dangerous.
If you must use a compressor with a storage tank (not recommended):
Remember: This method is not recommended and may cause damage or pose safety risks.
For safe and effective winterization, consider hiring a professional or using equipment specifically designed for sprinkler system blow-outs.
Find your stop and waste or shut-off valve. These come in various types and may be located in different areas of your property. The image shows three examples of stop and waste or shut-off valves.
This image shows the access point for a stop and waste valve at a typical residence. It's often located near the property line or close to the street.
Not all systems have an outdoor stop and waste valve. This image shows a shut-off valve located in a basement. Indoor valves are common in colder climates.
Here's an example of a regular ball valve located in the crawl space of a home. Always check various locations if you can't find your shut-off valve.
Begin by shutting off the water to the sprinkler system. Turn the valve clockwise to close it. Note that a stop and waste valve typically only turns 1/4 turn to fully close.
If your system has a backflow preventer, you'll need to drain it. Turn all shut-off valves to a 45-degree angle (halfway between open and closed). The exact procedure may vary depending on your specific backflow device.
Open all the test cocks on the backflow preventer to allow it to drain fully. You'll likely need a flathead screwdriver to turn these small valves.
Open any hose bibs or hydrants that are connected to the sprinkler system. This allows for complete drainage of the system.
Find all the sprinkler valve boxes on your property. These are typically green or black boxes partially buried in the ground.
Set all valves to the open position. Turn the solenoid (yellow arrow) and the bleed valve (red arrow) counterclockwise 1/4 turn. This allows the valves to drain naturally.
The center stem on most valves is a flow control, not an on/off switch. It's used to adjust water flow through the valve. There's no need to adjust this for winterization.
Set the sprinkler timer to the "Off" position. You can unplug it to save power, but be aware this may cause the backup batteries to drain. These batteries preserve the timer's memory during power outages.