How to Winterize Humble Your Sprinkler System

When temperatures drop, the water left inside your sprinkler system can freeze and expand. This expansion creates massive pressure that easily cracks plastic valves and bursts underground pipes. Winterizing your sprinklers before the first hard freeze saves you from costly repairs and ensures your equipment survives the winter.

Follow these actionable steps to properly secure your sprinkler system for the cold months ahead.

1. Shut Off the Main Water Supply

Your first step is to cut off the water source entirely.

• Locate the main shut-off valve for your irrigation system.
• This valve is usually found in a basement, crawl space, or utility room where it stays safe from freezing temperatures.
• Turn the valve completely off to prevent any new water from entering the pipes.

2. Drain the System

Removing the remaining water is the most critical part of winterization. You can clear the pipes using one of these three methods, depending on your specific setup:

• Manual Draining: Open all the manual drain valves located at the ends and low points of your piping. Leave them open so the water can drain out completely.
• Automatic Draining: If your system has automatic drain valves, they will activate on their own once you shut off the main water supply and system pressure drops. You should still briefly open the test cocks on your backflow preventer to ensure complete drainage.
• The Blow-Out Method: For areas with severe winter climates, use an air compressor to force out trapped water. Connect the compressor to the sprinkler system and blow air through each zone one by one until no more water escapes from the sprinkler heads.

3. Insulate Exposed Components

Any part of your sprinkler system that sits above ground needs a layer of defense against the cold.

• Wrap exposed pipes and the main shut-off valve with foam pipe covers or heavy-duty insulation tape.
• Protect your backflow preventer by covering it with a specialized insulated cover or bag.
• Secure all insulation materials tightly with outdoor-rated duct tape to block out freezing air. Do not block the drain ports on the backflow preventer.

4. Winterize the Controller

You also need to prepare your electronic sprinkler controller for the off-season.

• Turn the dial or switch to the “off” or “rain mode” setting. This stops the system from trying to run its usual watering schedule, but it keeps your programmed times saved in the memory.
• If your controller sits outside, make sure its weatherproof housing is securely closed and locked.

Taking the time to properly drain and cover your sprinklers protects your property. By following these steps now, you lock out the winter cold and prevent major pipe damage. When the ground thaws and spring arrives, your system will be completely intact and ready to keep your lawn green.