How to Use a Pressure Washer
A pressure washer is one of the most useful cleaning tools in your arsenal. They are particularly useful for things with lots of nooks and crannies that are hard to get into. They are great at getting hard-to-scrub grime off and significantly reduce the amount of elbow grease you have to put in. If you have the right kind, they are also great for cleaning large surfaces. They aren’t hard to use; however, if not properly used, they can damage the things you are trying to clean and can be dangerous. By the time you are done reading this you should know the basics to get started pressure washing like a pro.
What Can You Clean?
Before you fire up the machine you will want to make sure that what you are washing won’t be damaged by the pressure washer. It would be impossible to give you a comprehensive list of what should and shouldn’t be washed with a pressure washer, but there are some simple guidelines you can follow which will help you avoid damaging things. The obvious consideration is that you don’t want to be spraying things that can be damaged by water. Of course you also don’t want to pressure wash soft or fragile surfaces. For example, if your house has siding that is really old and brittle a pressure washer could end up blowing holes through it. Paints, sealers, and other coatings are also things you need to be careful with. A quality paint coating that is in good condition will be fine if washed with care. However, if the paint is starting to chip or crack then you should expect that the pressure washing will remove a lot of the paint. In some cases that is the desired effect. If you are unsure about whether or not pressure washing will damage the surface you’re working on, then you should start out with a test spot if possible. If, for example, you were to wash a fence, then start with a small spot on the back of the fence in a location that isn’t likely to be noticed. That way if you discover that the surface is being damaged then you can come up with a new cleaning plan before you leave some big eyesore on the front gate.
One of my first experiences using a pressure washer was when I borrowed a small gas unit from my brother to wash old weathered paint off of a wooden fence in my yard. The pressure washer got the job done, although it took a long time. I was using was one of the smaller consumer machine (about 2,500 PSI and 2 GPM…we’ll discuss pressure and flow and how they impact cleaning below). A larger machine could have cut the time in half. After I cleaned the fence I thought it would be good to wash my car (I had only owned the vehicle for a few months). I was almost finished cleaning the entire vehicle when I began to work on the grill. There were some bugs stuck to the chrome looking Chrysler logo on the front and I got really close with the nozzle and ripped a big strip of the chrome plating off. Ops! Now I own a company that provides pressure washing services with machines much more powerful than the unit I used to wash my car all those years ago. The way we wash vehicles is to first scrub it with a soapy brush then do the wash down with the power washer and never get closer than about 6 inches. Also, when you are washing around any decals, stickers, etc its important to hit those surfaces straight on (at a 90 degree angle). When you hit the stickers at a shallower angle then the water jet acts like a scraper and will peal those stickers and decals right off. By following those guidelines you can safely wash a vehicle without any trouble.
Steps for Use
Step 1: Connection and Setup
Now let’s talk about how to get the machine hooked up and started. You need water and power. Most pressure washers have a standard garden hose connection. So you can simply screw on the hose to both the spigot and the machine and turn the water on. Some systems draw water from a storage tank (this is more common in a commercial setting with a larger machine). If you are using an electric pressure washer make sure it’s plugged in to a working outlet and if you are using a gas unit then make sure it has fuel in it and enough oil. It’s important that you don’t run the machine without water hooked up and turned on as it can damage the pump if you do for too long or to frequently. Next you just need to make sure that you have the high-pressure hose connected to the machine and a pressure washing gun connected to the hose. It’s important to make sure that the hose and the gun are rated to for the pressure that your machine produces otherwise you will burst the hose and possibly get hurt.
Step 2: Release Air Pockets
Usually when you connect your hose there is air inside the hose. So when you first pull the trigger to start spraying you will notice that, instead of a steady stream of water, the machine will sputter for a short while. This is normal and not really preventable, unless you leave your machine hooked up to a water supply all the time. So just pull the trigger and wait for a minute or two for the machine to stop sputtering. Once it stops sputtering and you have a consistent stream of water running out you are ready to start washing. Some setups will allow water to flow through the pressure line even when the machine isn’t running. To see if yours will do this, with the water connected and turned on, simply pull the trigger and see if water comes out. It’s better to push all the air out before you turn on the machine if possible. The reason being that the pistons in the pump are lubricated by the water running through them. If you run air through the pump, then it will wear your pump out faster. Some machines won’t allow water through the pressure line unless they are turned on. For these setups you have no choice, so just go ahead and turn it on and pull the trigger to push the air out.
If you have the machine on and it continues to sputter or periodically surges while you are spraying, then likely you are not getting enough water to the pump. A standard house spigot will normally have enough flow to power a small consumer power washer, but if you are having trouble then you can easily test the flow rate of your spigot. Simply grab a 5 gallon bucket and and time how long it take to fill the bucket up. For example, if it takes 1 minute to fill up a 5 gallon bucket then your hose has a flow of 5 gallons per minute (GPM). Now just compare that flow rate with what your machine will output. If your machine does 1.5 GPM (a common rating for a consumer grade pressure washer) then you have plenty of flow. However, if you have a larger machine that does 6 GPM then you need to either get a higher flow water source. Also consider that it might be your hose that is restricting water flow. So getting a wider and or shorter hose could help. If you don’t have a higher GPM water source then you may want to get a water tank to store your water in and feed that into your pressure washer.
With everything connected and the air pockets pushed out of the lines you are ready to turn it on and start washing. On electric units you will have a power switch and on gas units you will either have a pull start or an electric start. It’s helpful to understand that, once the machine is running, the pump that pressurises the water is engaged and adding pressure to the hose and if you are not spraying water out of the gun that pressure has to go somewhere. This is handles with a device called an unloader that sits on the outgoing pressure line. It is a valve which will open up if the pressure gets too high and circulate the water back through the pump instead of out of the gun. If the unloader weren’t open for some reason, then the pressure would build up to a point where either a line would burst or the pump would seize and stop running. If you are drawing water from a storage tank then often the unloader will just dump the water back into the storage tank. However, most setups don’t utilize a storage tank and the water will just circulate in a small loop through the pump. The main downside to that is that if you leave the machine running for a long period while you are not spraying water, then the water circulating through the pump could heat up. If it gets too hot then it can start causing damage to the pump. So, long story short, don’t leave the machine running for too long while you aren’t spraying. As a rule of thumb, unless you know you have a setup that can handle it, then if you are going to stop spraying for longer than about 5 minutes just shut the machine off until you are ready to spray again. Some electric units will automatically shut off when you aren’t spraying and then automatically turn back on, once you pull the trigger.
Step 3: Start Spraying
This is the fun part…now you are ready to start cleaning. It’s a good idea to bring up some safety considerations. First, you should wear eye protection. Debris often are launched from the surface that are being cleaned and and find their way into your eyes. It’s not worth losing your vision over. The other important thing is to not spray it at or toward people or animals. A close up blast from even a small pressure washer will cut through skin with ease. Finally when you first pull the trigger it is a good idea to point the gun away from anything that could be damaged. There are two reasons for this. First, the first blast of water that comes out of the nozzle will have higher than normal pressure behind it. These initial bursts can sometimes be four times or more than that of your normal operating PSI. A burst of higher than expected pressure can damage a surface that otherwise would not be harmed by the pressure washing process. The second reason is that many guns have quick connectors that attach a nozzle at the tip. Sometimes these are not seated properly and when you pull the trigger the nozzle will get launch off the tip of the gun. A friend once had this happen and the nozzle broke through a window on a very expensive RV.
The next things to consider are spray distance, pattern, and angle. If you have a pressure washer that puts out 2,500 PSI that means that the PSI at the very tip of the nozzle is going to be that high. The pressure exponentially decreases with distance. So if you stick the tip of the nozzle directly on your foot and pull the trigger then 2,500 PSI will cut a hole right into your foot. However, if you were to pull the nozzle back to about 3-4 feet then it would feel like you are being sprayed with a mister. So don’t get too close to painted surfaces or any surface you fear may get damaged. You don’t even want to get too close on concrete. Sometimes concrete has a protective coating on it and if you get too close with the pressure washer you can end up etching off the coating and leaving permanent mark. The next thing to consider is your pattern of spray. Most of the time when I see someone use a pressure washer for the first time they tend to be a little unorganized with it. They sort of wave the gun around at random and leave clean stripes all over the place. While this might be fun, it will take you a lot longer to clean this way. Instead pick a good cleaning distance usually between 5-9 inches away from the surface, depending on how dirty it is and how fragile the surface is. Then start at the top (if possible) and keep the tip of the gun at a constant distance and move horizontally across the surface. When you get to the end move the wand down so that there is about an inch of overlap with your last pass and move back the other direction. Just keep doing this down the surface until you get to the bottom. Finally, you will want to roughly keep about a 90 degree angle relative to the surface you are cleaning. The exception would be if you are cleaning on a surface where you aren’t worried about peeling paint, stickers, etc., then you can use a shallow angle to try and scrape hard to get grime off. If you keep a consistent distance and pace and have an appropriate overlap then you won’t leave little stripes of unclean spaces. One mistake that people make is that they will stand in one place and rotate at their waist to move the wand across the surface. The problem with this is that you can’t maintain a consistent distance from the surface you are cleaning and the spaces on the left and right of the person cleaning will not be as clean as those directly in front of the person cleaning.
The last piece of advice is to realize that high pressure won’t clean everything. Grease and hard water spots are examples of things that don’t clean off well without a solvent. So do a little research on what you are cleaning and see if you need to also use some type of solvent or chemical with your pressure washing.
Small jobs can often be taken care of inexpensively with a consumer grade pressure washer. However, bigger jobs will take a lot longer time and some will impossible without a larger machine. The bigger machines could run you from about $4,000 – $12,000. Many businesses and individuals don’t want to spend a lot of time and/or money doing it themselves and chose to hire a pressure washing service to do the cleaning. AJET Services has professional grate equipment that allow us to get the job done in a fraction of the time and our experienced and trained employees know how to not damage the surfaces of the things they are cleaning and make it look really good when they are done. If you want to have a professional service do the cleaning for you give AJET Services a call 801-330-0398 or email at email@example.com.
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