How to Winterize Your Sprinkler System

Cortada Landscape Design | Irrigation System | Design & Installation | Miami, FL | Residential Irrigation System Project

Do you have an automatic sprinkler system in your lawn, yard, or garden? The weather during the summer is often friendly to your water supply system. However, as temperatures start to drop, you must winterize the installation properly. During the winter, there’s a real danger of a pipe bursting or leaking on a joint because of frozen water. It’s imperative to remove all water from the irrigation system just before the first signs of frost set in.

The valves, joints, and fittings on your sprinkler system are sensitive to ice building up inside. To prevent damage to your prized possessions, move quickly to winterize properly. Here is a simple yet effective DIY guide. Following the steps will help you get your sprinkler system ready for winter efficiently.

Step 1: Shut off the water supply

This should go without saying, but we will remind you just in case you have forgotten: Shut off the water. Turn off the main water supply to protect it from freezing. This is also a good time to inspect the main valve for signs of damage by the pressurized water. Wrap the main valve with a plastic bag and a foam insulation tape. This prevents it from the harsh climatic conditions associated with ice and frost.

Step 2: Insulate the sprinkler system

Insulate your system’s main shutoff valve. If you don’t have one installed already, purchase a new one to protect the entire investment. While you’re at it, you must insulate all the aboveground piping. The best material for this work is foam insulating tubes as they are durable. To make the whole insulation even better, consider using a self-sticking tape.

Step 3: Remain in control

If you have installed an automatic sprinkler system, shut off the timer on the device. Most modern sprinkler controllers have a rain mode that automatically shuts out all signals to water valves. There is no harm if you check it if you want to be sure. While shut down, it continues to maintain the programming data, such as valve run times and start times.

In fact, the timer keeps running in winter. If you’re unsure about the operation of your system, simply shutting off power to the apparatus will ensure proper winterizing. The only drawback in doing so is you’ll have to reprogram the system next summer

Step 4: Drain the system manually

Keeping the water from flowing is one thing but removing the water from inside the sprinkler system is another. If you leave it there, it will freeze, expand, and cause the piping to break. Simply carry out a manual system drainage yourself. First, shut off the backflow preventer to keep the sprinkler water from flowing back into the main supply.

Next, open the sprinkler system’s manual drain valve. This will let any water still inside the system to flow out easily, thanks to the power of gravity. To find these valves and preventers, read and follow the instructions on the manual that came with the sprinkler system. If these are not clear, call your local irrigation specialist as the procedures may vary from one model to another.

Step 4: Blow the system out

There is no guarantee that the manual draining of water in the sprinkler system will be 100 percent effective. You see, underground pipes can shift over time. The gravity drainage option is not enough, especially where low spots collect water. You don’t want any water to stay behind as it will freeze, expand, and cause the pipes to burst. Therefore, use compressed air to blow out any water trapped in small pockets inside the sprinkler system.

Using an ordinary air compressor, start by closing the backflow preventer valve. Another name for this is a pressure vacuum breaker. Next, remove the plug screwed on to the blowout port and quickly connect the compressor’s air hose. You might be surprised by how much water is still inside even after draining the sprinkler system manually.

You will only need a little air pressure to blow out your sprinkler system effectively. Remember, too much pressure can burst the pipes and damage the valves. For this reason, only use an air compressor that has a rating of no more than 10 cubic feet per minute (cfm).

Step 5: Setting up the air compressor

Did you install your sprinkler irrigation system in the last couple of years? If yes, then you should have the original layout that indicates the irrigation gallons per minute (GPM). Now, let us crunch some numbers. Each sprinkler head has a GPM. Divide the overall GPM of each by 7.5. The total is the correct cubic feet per minute you will need to clear the water from the system.

Alternatively, rent a 10-cfm air compressor from your neighbor or at the local hardware store. Set the regulator on the air compressor to the maximum 80 psi if your sprinkler system boasts of rigid piping. Otherwise, a setting of 50 psi is enough to blow air into your ordinary black polyethylene pipes. Do not blow out the air for longer than necessary. It’s easy to burn out the plastic gears and surfaces with the compressed air. This is especially true now because there’s no water to cool things down.

Benefits of winterizing your sprinkler system

As we have mentioned earlier, water expands when it freezes. Let us put that into proper perspective. When you freeze 11 cubic feet of water, you’ll have at 12 cubic feet of ice. This is a process called hydro expansion. Pipes, water tanks, valves, and pumps expand, burst, and, eventually, break. This process renders them useless.

There is so much information available on how to properly winterize. If you do not know how to DIY, hire a local irrigation expert for a small fee. When sheer ignorance causes damage, you could easily void your warranty on your expensive installation. Besides, purchasing and installing a new irrigation system will cost you money. Now, there is no excuse for failing to observe the importance of winterizing your sprinkler system.