Filling the Water Can

   The water can is one of the simplest, yet often overlooked tools on our rigs. When it’s filled and pressurized correctly, it can provide quick, temporary fire suppression, helping firefighters get to victims or protect exit routes when a hose line isn’t immediately available. But what does “properly filled” actually mean? During apparatus check, many firefighters just check the pressure gauge on the water can, thinking that’s enough—but there’s more to it. In this article, we’ll walk through how to ensure your water can is ready to perform for you.          

   A correctly filled water can gives you about 50 seconds of use, with a stream that can reach up to 50 feet. That sounds straightforward, but just checking that the gauge is in the “green” during rig checks simply isn’t enough. Broken gauges can still show green, and having the right pressure isn’t the only requirement. You also need exactly 2½ gallons of water in the can. If it’s overfilled or underfilled with water, the can won’t work as designed thus, leading to sub-par performance. A properly filled can should weigh about 29 pounds. Now this weight will vary depending on the manufacturer but check the side of your can, it should clearly state how much the can should weigh when properly filled with water. To ensure that the proper amount of water is in the can, it is essential to pick it up and feel for the appropriate amount of weight.

   In a recent search class I taught that incorporated the water can, many firefighters shared the same surprising feedback: “I didn’t know there was a proper way to fill the water can.” So let’s take a closer look at how to do it right.

   Start by removing the handle assembly (which includes the nozzle, hose, and pickup tube). Inside, you’ll see a plastic tube inside the neck of the can. This is called the fill tube. If the fill tube is missing, a new one can be purchased for a few bucks online. Make sure the fill tube is seated properly by pressing down on it firmly. If the fill tube floats or wobbles while you’re filling the can, it’s not correctly in place, and it won’t measure the water accurately. Once the fill tube is secure, begin filling the can. When you reach 2½ gallons, the fill tube will cause water to spray out the top. If you’re using a garden hose, this usually takes around 25 seconds. 

   Once the can is filled with 2½ gallons of water, reattach the handle assembly and tighten the nut by hand. There’s no need for tools here—just a snug fit is enough. The manufacturer recommends about 100 pounds of pressure to secure it.

   Next, it’s time to pressurize. Set your air compressor to around 125 PSI to ensure there is enough pressure to pressurize the can to 100 PSI. The gauge on the neck should move into the green as the air fills, and you’ll know it’s ready when the air stops flowing. Again, make sure the pressure gauge is working properly before relying on its reading.

   Finally, put the pull pin in place, and your can is good to go.

   A couple of additional tips: First, always operate the can in an upright position. The pick up tube reaches to the bottom of the can, where the water is. If the can is on its side, the tube may start pulling in air instead of water as the water level drops.

   Second, consider swapping the standard pull pin for a 2½” hitch pin from your local hardware store. The original pin can sometimes fall out, and while many departments use a tamper seal to secure it in place, that can make it tricky to remove with fire gloves on. The hitch pin is easier to handle and stays in place. If you choose this option, tie the hitch pin to the area behind the pressure gauge using paracord, making it easier to pull with gloves.

   Lastly, think about getting a strap for easier carrying. There are great commercial options available, but you can also find simple DIY solutions with a quick trip to the hardware store.

   In closing, the water can may be a basic tool, but when prepared and used correctly, it can be a real asset on the fireground. By taking the time to ensure it’s properly filled, pressurized, and maintained, you’ll have a reliable means of temporary fire suppression that can make all the difference in critical moments. Small steps like properly utilizing the fill tube, swapping a hitch pin for the pull pin, and adding a carrying strap can improve both functionality and ease of use. 

Training Objectives

   Upon completion the firefighter should be able to….

   • Identify if the water can is properly filled.

   • Properly fill the water can.

   Training articles are archived at bit.ly/IowaFirefighter   

   Cole Kleinwolterink is a member of the Waukee Fire Department, Granger Fire Department, and Fire Science instructor at Des Moines Area Community College. Feel free to reach out to him at kleinwolterinkc@gmail.com with any questions, comments or inquiries.