It’s raining outside, but you need to get that last pressure washing project done. Or, you’re just renting your pressure washer, and time is running out. Is it safe to brave the outdoors and pressure wash in the rain? The short answer is it depends on your pressure washer and how bad the weather really is. While some pressure washers are rated to withstand some water, some weather can impact your safety or the quality of your pressure washing projects. You should not expose other pressure washers to rain at all, or risk electrocution or damage to the pressure washer.
You may think that because a pressure washer has water inside of it, it must be waterproof. However, plenty of gas and electrical appliances that use water can’t stand out in the rain. It’s one thing to design a product that has a water compartment or hose in it, and another to design a product that won’t let a drop of rain get in the engine or electrical components.
Of course, some pressure washers can stand light rain perfectly well. In fact, you may hear of pressure washer contractors who prefer to work in the rain. Not having to stop for the rain helps them make money on the days that roofers and landscapers would have to call it quits. Some pressure washing professionals even argue that rain can help them rinse off their work.
However, just because the pros do it, doesn’t mean you’ll be safe. Professionals are more likely to be using high-end equipment that is rated to be perfectly waterproof. So, the first thing you need to ask yourself is: does my pressure washer have a waterproof rating?
Can A Pressure Washer Get Wet?
Whether or not your specific pressure washer can get wet depends on several factors. Your first step to determine if you can get your pressure washer wet is to check with your pressure washer’s manual and on its body for rating marks. If you find a warning in the manual that says not to use your pressure washer in the rain, listen to it. You won’t be able to sue the manufacturer if you get hurt using it in the rain, and this will likely also void your warranty on the pressure washer.
If the manual doesn’t say anything about water, but it does have an Underwriters Laboratories (UL) or rating from another third-party testing agency, you should look up the rating.
You may read guides that tell you any rating from UL is good enough. That is simply not true, as UL and other rating agencies have different standards for different products and features. You should look up the specific product’s rating (it should be listed as a number right near the UL symbol) and what it means.
While you’re looking, you may find marks and standards that have nothing to do with your gas or electric pressure washer’s waterproofness. For example, the Pressure Washer Manufacturer’s Association’s (PWMA) standards are about performance. They measure for the pounds per square inch (PSI) and gallons per minute (GPM) but say nothing about whether your pressure washer can be used in the rain.
Even if you find a waterproof rating, you should also be aware that there are different types of waterproof. Consider the National Electrical Manufacturers Association’s (NEMA) rating system for enclosures. By enclosures, they mean the outermost part of electrical equipment. NEMA recognizes three levels of waterproof: safety from a quick hose down or splashing of water, safety from temporary submersion in water, and safety from prolonged submersion in water.
It is much more challenging to create something that can withstand water submersion than an occasional splash of water. While NEMAs 4, 4X, 6 and 6P ratings for enclosures can handle splashes of water, only 6P can handle the occasional prolonged submersion in water.
Your electric or gas pressure washer may be rated for an occasional splash of water used to clean it, but not to stand in a flooding driveway or run when directly exposed to heavy rain. By the way, most pressure washers will warn you that they cannot be cleaned with their own wands. The plastic body of most pressure washers simply cannot withstand the pressure the machine produces.
Ultimately, you need to find and understand the rating to understand in which situations it’s okay to get your pressure washer wet.
When You Shouldn’t Pressure Wash in the Rain
You’ve found a rating that says your pressure washer is safe to use in the rain. Great! But you should still use common sense and avoid using your pressure washer in weather that is dangerous to you. For example, if you are pressure washing a pool in the rain, the pool surface may be too slippery for you to pressure wash safely.
Weather conditions that make it unsafe to pressure wash include:
- Lightning: You should, of course, not be outside when there is the possibility of a lightning strike.
- High wind: Strong winds are a problem for pressure washers because it may blow the wand, or your arm, in a direction you’re not expecting. Remember, a pressure washer has the potential to do a great deal of damage if sprayed on something you don’t intend to spray, including your own feet. If sudden or strong gusts of wind are in the forecast, it’s best to stay inside.
- Heavy rain: Heavy rain may distort your vision, and you should never use equipment as powerful as a pressure washer if you can’t see exactly what you are doing. Also, if your driveway or wherever you’re working may flood, even with an inch or so, you likely should not be using your pressure washer. Few pressure washers are rated for any level of submersion.
- Hail: Hail can be dangerous both for you and your pressure washer. Even light hail can impact the pressure washer and create dents.
- Snow: Pressure washers should not be used in freezing conditions because ice can ruin their internal components. You should winterize your pressure washer before winter and store it somewhere dry.
- Extreme heat: A pressure washer can work in high heat, but maybe you can’t. Be sure to monitor yourself for heat illness if you’re trying to finish a project in extreme heat.
Pressure Washing Projects That Could Be Ruined By Rain
Light rain can help you rinse off some projects. However, you should also consider whether the rain could interfere with the quality of your project, or if pressure washing during the rain could increase your odds of polluting the environment.
- Detergent: If you’re using soap in or with your pressure washer, you might consider if the rain might water down your soap solution. Rain may also wash off your cleaning solution before it has had time to work.
- Chemicals: Some cleaning projects require the use of staining, sealing, finishing or cleaning chemicals. While you typically will not put these chemicals in the pressure washer, you may still want to postpone the whole project until after the rain. You don’t want to let the rain wash dangerous chemicals onto your landscaping or down to the sewers where they may cause environmental damage.
- Sealing and staining: However, you also don’t want to start by pressure washing during rain and seal or stain the surface after. Generally, you shouldn’t allow surfaces that should be stained or sealed get rained on before their sealant or stain is applied. The water may damage the surface beyond repair or significantly shorten its lifespan.
Can You Leave a Pressure Washer Outside?
No, you should not leave your pressure washer outside, even if it is rated for use during the rain. Every time your pressure washer is exposed to water, chances increase that it will be damaged by it. You probably made a big investment in your pressure washer, so don’t shorten its lifespan.
If you’re in an area where you get snow, there is even more reason to bring your pressure washer inside. If water gets inside of the pressure washer and freezes, it could break completely.
Have I Ruined My Pressure Washer by Exposing It to Rain?
Unfortunately, maybe. Electrical and gas pressure washers have components that can be permanently ruined by exposure to water.
If your pressure washer got wet and now refuses to start, or doesn’t seem to be working well, you should check in with a repair shop or another professional to see if it can be salvaged.
General Rules for Using a Pressure Washer in the Rain
To sum everything up, here’s what you should know about using a pressure washer in the rain:
- Always check with the manufacturer before you use their product in the rain
- Look for certifications about waterproofness on your pressure washer and look them up to understand what they mean
- Understand the difference between waterproof ratings for splashes and submersion in water
- Decide if the weather is safe for you and your project as well as the pressure washer
- Don’t expose your pressure washer to water unnecessarily unless you’re okay with shortening its lifespan
- Don’t store pressure washers where they can be rained on, even if yours is rated for waterproofness
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