How Much Antifreeze Do I Need to Winterize My Sprayer?


Using antifreeze can help protect your sprayer from damage when it is stored during the winter months. This is the case whether you have a turf sprayer, golf course sprayer, 3-point sprayer, tree sprayer, etc. So how much antifreeze do you need to winterize a sprayer? After doing some research and making some calls here’s what I found out.

In order to winterize your sprayer you will need enough antifreeze to fill the sprayer pump and the fluid path from the tank to the boom. This includes the valves, hoses, nozzle bodies, and accessories. The exact amount will vary depending on your sprayer type and size but typically it will take between 2 to 3 gallons of antifreeze to properly prepare a lawn or turf sprayer for winter storage. Let’s take a closer look at the different types of sprayers and what it takes to winterize them. 

Sprayer Size Matters

The size of your sprayer is the biggest variable in determining how much antifreeze you will need to winterize your sprayer. Larger pumps will obviously hold more liquid than smaller ones, and sprayers with longer lengths of hose or booms will hold more volume as well. 

The simple simplest way to ensure you have antifreeze completely throughout your system is to use the pink-colored RV antifreeze and watch until the water leaving the sprayer has turned pink. You will want to make sure you have enough on hand to accomplish this before you start. To get a rough idea of how much antifreeze you will need, you need to determine the capacity that your sprayer pump, hose, boom, and all the other parts of the fluid path. 

How to Determine the Amount of Antifreeze You Need for Your Sprayer

While it may not be possible to figure this out exactly, you can get a good idea of the volume your system will hold by measuring the length of the hose, plumbing, and boom. Then if you know the inside diameter of your hose and boom, you can calculate how many gallons of liquid your sprayer’s plumbing can hold.

Inside Diamter (Inches)Volume Per One Foot of Hose (Gallons)*
¼ inch0.00255
⅜ inch0.005737
½ inch0.0102
¾ inch0.0229
1 inch0.0408
1.5 inch0.0918
2 inch0.1632
*Approximate

Small Sprayers

Spot sprayers, small boom sprayers, and other sprayers used for lawn care will not require much antifreeze, in many cases, you will need less than one gallon to winterize your lawn sprayer. 

Example: I have a small sprayer that I use on an ATV and mower. It has a few feet of ½ inch inside diameter suction hose, a 12-volt diaphragm pump, and about 7 feet of ⅜ inch inside diameter hose that feeds two ⅜ inch nozzle bodies. There is a ½ inch poly “T” fitting and a regulating valve that bypasses back to the sprayer tank. 

Using the chart above, I know that the hose on the sprayer will hold less than 0.08 gallons of liquid. The pump will hold some, and if we add some cushion for the regulating valve, the total amount of antifreeze needed is going to be well less than one gallon. This means that I can probably winterize this little sprayer for many years with just one gallon of antifreeze. The cost of this is well with avoiding the cost of replacing a pump, valves, or poly fittings. 

RELATED:

Larger Sprayers 

Pull-Type Sprayers, UTV Sprayers, 3-Point Sprayers, and other sprayer types typically used for turf and field spraying will clearly require more antifreeze. Where a 12-volt diaphragm pump may hold a couple of ounces inside the housing, a centrifugal sprayer pump will hold much more. Larger sprayers will utilize larger diameter hoses and larger strainers as well. This all adds up to a greater volume of antifreeze needed. 

As with a smaller sprayer, you can add up the length of the boom, all the runs of hose, and identify the hose sizes to find an approximate capacity. For example, let’s assume you have a 20 boom with ½ hose, as well as a spray gun with another length of 25 feet of ½ inch hose. That’s going to require approximately a half gallon just for the boom and spray gun hose, not to mention all the rest of the plumbing from the sprayer tank, agitation, strainers, etc.

I reached out to one sprayer manufacturer about the approximate amount of antifreeze it would require for their 200-gallon 3-point sprayer with a 23 ft boom and a 15 ft length of hose with a spray wand. They said it would take about 2-3 gallons, enough to fill all hose and accessories. 

For the large pull-type and self-propelled agricultural sprayers, the volume of antifreeze needed jumps up considerably. These sprayers have complicated plumbing setups, it is best to refer to your owner’s manual or ask your equipment dealer for some guidance. 

Why Use Antifreeze to Winterize a Sprayer?

In addition to protecting the sprayer from freezing. The antifreeze will lubricate the components of the sprayer and protect against corrosion. 

How do I add Antifreeze to My Sprayer?

Pour the antifreeze directly into the sprayer tank. Turn on the pump and run it through the entire system. Antifreeze should be seen coming out each nozzle and If you have a handgun on your sprayer, be sure that you open it until the liquid coming out turns pink. Leave the antifreeze in the sprayer until next year. Before the next season drain the antifreeze and flush the sprayer with fresh water. 

What Type of Antifreeze Should I Use to Winterize My Sprayer? 

After combing through operator’s manuals for several different sprayers. I can tell you that nearly all of them recommend RV antifreeze. This is because it is considered non-toxic, and generally safer for the environment than automotive antifreeze. 

The Champion Marine and RV Antifreeze is safe for use with the different types of materials used in sprayers like EPDM rubber hoses, poly tanks, etc., It also does not need to be premixed, it can be added right to the sprayer and provide protection.

Can’t I just Drain My Sprayer Completely in the Winter?

Even if you have a small spot sprayer or backpack sprayer, it is very difficult to drain all water from your sprayer. You can use an air compressor to blow out the sprayer and try to remove all water, but it is hard to ensure that no small amounts of water are sticking in small recesses inside the sprayer valves, bypasses, and nozzle bodies. Even small amounts of water can expand enough when they freeze to cause cracks or damage. Water and chemical residue will find their way into the spaces between threaded fittings and seams. If you cannot store your sprayer in a climate-controlled building, using anti-freeze is the safest way to avoid problems. 

If you are looking to winterize your sprayer for the first time, you can find more information about winterizing specific sprayers in these posts:

Shane

I have more than a decade of experience using, building, studying, and testing sprayers in several applications. With the knowledge I have gained I want to provide straight forward and detailed answers for DIY homeowners, farmers, and commercial turf and tree care pros.

Recent Posts