Pressure washers are great for speeding up a lot of outdoor cleaning jobs. You can use them to clean your patio, driveway, gutters, pool, etc. Some people use pressure washers to clean their car, because it is much faster and easier than using a bucket and sponge. But which type of pressure washer is right for you?
Pressure washers are available in both electric and gas-powered forms, each having its own unique advantages and disadvantages. Electric power is cleaner, and quieter. It is what we would recommend for the average homeowner who doesn’t have a lot of experience using outdoor power tools. The main benefit with electric models is how easy they are to maintain. No need to mix gas and oil, all you have to do is plug them in and you’re ready to start cleaning. Gas power does have its advantages as well, for instance- you cannot clean every corner of your driveway or yard with an electric model since the cord will limit how far you’re able to go. On top of that, it is a well known fact that gas pressure washers are simply more powerful.
The average gas powered pressure washer generates around 2200 to 2500psi of pressure, while the average electric pressure washer delivers around 1500psi. Gas models are undeniably better for heavy duty jobs, such as removing caked-on dirt from paved walkways. And, gas powered pressure washers are going to be more portable despite their heavier weight. The average homeowner typically uses their pressure washer for small to medium duty jobs around the house, like cleaning the BBQ grill or wooden deck. Which means, you don’t always need the additional range of gas, and ease of use might be your primary requirement. In our article, we shall compare Electric vs Gas pressure washers and give you the definitive answer on which is better for your specific needs. We are also going to compare PSI vs GPM to help you decide on the right pressure washer for a specific application. And finally, we will take a brief look at the various nozzle types you find on most pressure washers.
How Does a Pressure Washer Work?
Let’s start off by explaining how a pressure washer works. It clears dirt, grime, paint, oil, etc. from surfaces by spraying high pressure water from a tiny nozzle. The water being supplied to a pressure washer is usually around 15 to 20 psi, from a cold water feed hose. And this low pressure water is then forced through a pump which pressurizes it. The type of pump used in a pressure washer is similar in concept to something like a sump pump, but the required characteristics are very different.
A sump pump is designed to push out as much water as possible from a confined area. It is a high flow, low pressure pump. On the other hand, a pressure washer is meant to release a powerful jet of water for cleaning purposes. So it uses a high pressure, low flow pump design. All pressure washers utilize reciprocating positive displacement pumps. Basically, a reciprocating pump is one that uses pistons, plungers, or diaphragms.
There are 3 types of pumps you’ll find in pressure washers :
- Wobble pump: Self priming, used in models with pressure under 2500psi and flow rates under 2GPM.
- Axial cam pump: Used in most pressure washers rated for 3500psi or less, with the advantage of being small and lightweight. Longer lifespan compared to wobble pumps.
- Triplex plunger pump: Prosumer and commercial use only (3000psi and above). Extremely efficient, and longest lifespans thanks to stationary seals. Lower operating speed, which helps it run cooler for an extended period of time.
The pump isn’t going to pressurize water by itself, it needs something to drive it. Gas- powered pressure washers utilize 4- stroke or 2- stroke engines to drive their pumps. A 4- stroke engine is more fuel efficient and generates lower emissions compared to a 2- stroke, but generates less power with respect to size and is more complicated. Two stroke engines are lighter and smaller, but they are inefficient and have lower lifespans.
Most electric pressure washers are corded, although recently we’ve seen a few cordless models being released from Worx and JPT. Corded pressure washers are powered by AC induction motors, which are fed by the 120V AC outlets in your home. Cordless models use DC motors and are powered by rechargeable lithium ion battery packs.
The water coming out of a pressure washer’s pump is fed into a high pressure hose, at the end of which is some sort of cleaning attachment. You cannot use regular tubing in place of the high pressure hose, since it has to withstand nearly 200 times atmospheric pressure. The hose included alongside your pressure washer uses multiple layers of high density plastic, and is reinforced with wire mesh. A safety margin of 300 percent on pressure washer hoses means that a hose rated for 3000psi can withstand up to 9000psi before it breaks.
Attachments — Pressure Washer
There are a variety of attachments available for pressure washers. You have the pressure washer wand, which accepts nozzles at the end. Then, there are various types of nozzles, such as the turbo nozzle, black tip, red tip, etc. Each nozzle will generate a different type of spray pattern, some wide while the others are narrow. The narrower your spray angle, the more force it generates. A red tip or 0° nozzle can put a hole right through your boot (and your feet), if you aren’t careful with it. Other pressure washer attachments include the surface cleaner, which is a must-have if you want to clean large flat areas in less time.
The surface cleaner attachment consists of a rotating nozzle bar placed inside a cylindrical housing. There is a nozzle on each end of this spinning bar, and the force of the pressurized water is what causes this bar to rotate. The nozzles aren’t pointed directly at the ground; they are placed at an angle for maximum cleaning performance across a wider area. When this bar spins, it distributes the pressure across a large area compared to a regular nozzle. If you’re cleaning garages, driveways, or decks, a surface cleaner attachment can reduce your cleaning times by 50 percent or more.
Pressure washers can also accept brush attachments, which are used in combination with low pressure settings to clean cars and boats. There are also some proprietary brush attachments provided with Karcher and SunJoe electric pressure washers. These attachments utilize a spinning brush to loosen up dirt and dust more easily, so the water can then away the debris.
Electric vs Gas Pressure Washer | Pros vs Cons
Now that you understand how a pressure washer works, it is time to discuss the advantages and disadvantages of both gas and electric models in more detail.
Gas pressure washers
The average gas powered pressure washer generates anywhere from 2000 to 2800 pounds per square inch of pressure. And the commercial grade models can go as high as 4000psi, which is needed for paint prep or graffiti removal. When buying a gas powered pressure washer, you will have to choose between residential and commercial models. There are “semi -pro” models as well, which can handle everything a lower end commercial model can, while still being usable on a day to day basis for homeowners. Higher end models are equipped with triplex plunger pumps which last longer and run cooler, along with heavy duty engines. The units with Honda GX series commercial engines are highly desirable, due to the efficiency and reliability of this engine type.
Four stroke engines with overhead cams or overhead valves will cost you more, but they run cleaner and are more fuel compared to a 2- stroke. If you want pressure washer rated at 3500psi or higher for commercial purposes, look for a heavy gauge welded steel frame, solid steel axles, and never flat tires. These will ensure that the unit can take a bump during transportation or on the jobsite. A strong tubular steel frame keeps the engine, carburetor, fuel tank, etc. protected from external impacts, and will last much longer compared to any electric model out there. You also want a pro- style steel spray wand with quick connect couplings for maximum productivity.
Because they are so overbuilt, commercial grade gas powered pressure washers will last much longer than even the most premium electric models. Steel frames are tougher than plastic shells, and solid steel axles will endure much more abuse compared to what you find on homeowner models. If you want a pressure washer that can clean large sections of fences, strip paint, and remove caked up grime from brick stairways, nothing beats gas power. Keep in mind the fact that a good gas powered pressure washer is going to be more expensive compared to electric models, and it will cost you more to maintain in the long run. You’ll have to spend money on gasoline and engine oil. Sometime in the future, you’ll have to replace the spark plug or change out the air filter. Do all the maintenance work, and your gas powered pressure washer will easily last 10 years. The costs are justified if you work on a ranch, have a large property, or run a business. Otherwise, you’re better off getting an electric model.
Electric Pressure Washers
The average electric pressure washer generates anywhere between 1300 to 1800 pounds per square inch of pressure. This is nothing to scoff at, but pales in comparison to gas power. Nevertheless, as an average homeowner living the city, you rarely need more than 1500psi from your pressure washer. Electric pressure washers are good for light- duty residential tasks- cleaning your car, outdoor furniture, windows, and mildew removal. For the aforementioned tasks, you only need 1300 to 1800psi and 1.5GPM. Once you step it up to heavy- duty residential tasks- cleaning concrete, brick walls, sidewalks, paved driveways, etc. you are getting into gas power territory. But there are still some high end electric models with more than 2000psi of pressure which can handle these tasks.
With the right nozzle, your electric pressure washer can-
- Clean concrete
- Clean flagstone
- Clean siding
- Clean your car
- Clean vinyl moldings
- Strip paint
- Clean decks
With a variable pressure wand, you can handle the most delicate of jobs while still packing enough power to rip off any stubborn dirt from your driveway or patio. Most homeowners use their pressure washer to clean BBQ grills, gutters, shutters, siding, fences, etc. How many times do you think you’ll be stripping paint or removing graffiti? If you don’t need all the power of a 3500psi gas pressure washer, why bother yourself with all the maintenance hassles that come with owning one? Carb cleaning and tuning, winterizing, air filter cleaning, fuel storage and mixing, all of these annoyances can be avoided by just purchasing an electric powered pressure washer. It will get the job done with much less noise, and doesn’t harm the environment. Oh, and you won’t smell like gas when you enter back into the house after cleaning that pool.
Here is a summary of the Pros and Cons for both power types :
- On average, these are priced lower compared to gas, and have near zero maintenance expenditure.
- Compact size, because the electric motor takes up less space than a gas engine. Weight is reduced by the use of plastics and other polymers instead of steel frames.
- Easier to start, because all you have to do is press the trigger. Electric motor can start and stop instantly, so no unnecessary idling which could potentially damage the pump.
- No winterization procedures required for storage during winter season. With a gas- powered pressure washer, you have to completely drain the tank and fuel lines, then you have to add fuel stabilizer to the gas.
- Zero hassle. No carburetor cleanups, or spark plug changes. No fumes, and zero pollution. You also don’t have to worry about storing fuel or mixing oil and gas.
- Relatively quiet compared to a gas- powered model.
- Much safer for cleaning cars or windows.
- Much simpler to operate, because you don’t have to mess around with chokes or primer bulbs.
- Less cleaning power compared to gas units.
- Relatively lower lifespan on average, because electric pressure washers aren’t as rugged as a steel framed gas pressure washer.
- With corded models, you can’t clean anything that is more than 100 feet away from the outlet.
- Pumps used in most electric pressure washers aren’t intended for heavy duty applications, and will heat up after a while. Commercial gas powered pressure washers are equipped with triplex plunger pumps which have a much longer lifespan.
- Most gas- powered pressure washers are far more powerful than the average electric model. They are great for cleaning hard surfaces like concrete, marble, brick, stone, etc.
- Gas models are more portable. They aren’t tethered to a cord, and are generally equipped with larger wheels which allows you to roll a gas pressure washer over rougher terrain- gravel, dirt, etc.
- Despite being costlier on average, gas pressure washers are available across a wide range of prices. You have the residential models with cheaper pumps and lighter frames. Then come the slightly more expensive prosumer models with extra features like OHC or OHV engines and welded steel frames. Finally at the top, there are commercial models with high performance air filters and triplex plunger pumps.
- Despite requiring more maintenance work, gas pressure washers tend to last longer because they are built with more substantial frames and heavier duty pumps.
- You can clean large driveways, decks, and sidewalks in a relatively short period of time, because gas pressure washers are rated for higher GPM.
- Higher upfront costs and greater maintenance expenditure over time when compared to electric pressure washers.
- Gas- powered pressure washers are larger compared to their electric counterparts, so they require more storage area. They are also heavier because of the gas engine, so your wife or grandpa might have a hard time moving a 3500psi commercial grade pressure washer around the yard. Keep that in mind before you decide to purchase one.
- Starting one of these up in cold weather can be a frustrating experience, as you have to tug on a recoil starter and constantly play with the choke. On an electric model, you just push a button and it starts up without any hiccups irrespective of the weather outside.
- If you aren’t comfortable with standing next to an extremely loud gas engine that spews toxic fumes a couple feet away from you, you might want to stay away from a gas model.
- General maintenance work can be very tiresome if you aren’t used to gas powered tools before. The air filter must be cleaned every once in a while, the spark plug has to be removed and checked for carbon deposits, the spark arrestor needs to be examined, and you have to mix oil with gas in the right ratio for 2- stroke engines.
PSI vs GPM | Which one is more important?
PSI or pounds per square inch denotes the amount of pressure being exerted by the water as it exits through the 0° red colored nozzle. Pressure is simply force exerted per unit area, so the smaller you make an area the more force you’re applying on it. By changing out nozzles, you can increase or decrease the area of impact. A wider nozzle will release a larger “fan” of water, covering more area but with reduced force. A tiny opening means you get a concentrated jet of water which isn’t very good for rinsing and general cleaning, but can be used to strip away caked mud or oil stains.
So if we can vary the pressure simply by changing a nozzle, what’s stopping people from using electric pressure washers for heavy duty applications like paint prep and concrete cleaning? Can’t they just attach a 0° nozzle and blast away all the dirt just as easily with an electric model? Well, it is not that simple. When you increase pressure, you are sacrificing volume. Think of it this way- a pressure washer equipped with the red nozzle shoots water at a speed of 243mph. A tsunami after entering shallow water travels at a speed of 30 to 50mph. But that is enough to wash away houses and lay waste to entire cities. The difference between a tsunami and your pressure washer is pretty obvious. Volume is just as important as pressure if you want to understand the overall cleaning ability of a pressure washer.
Some people calculate the net cleaning power of a pressure washer in CU, or Cleaning Units. CU is obtained by multiplying PSI with GPM (CU = PSI x GPM), and the GPM for most household pressure washers is between 1.3 to 2.5 while pressure varies between 1300 to 2800psi. The toughest, most powerful commercial grade pressure washers can supply more than 4 gallons of water per minute and are rated for maximum pressures in excess of 4000psi. Remember, the maximum pressure rating you see on the box of your pressure washer is calculated only after installing the 0° tip, and the measurement is taken close to the tip. As you move farther away from the nozzle, pressure begins to fall gradually. Once you attach a 65° soap nozzle and hold the pressure washer 5 feet away from your car window, that 2500psi maximum rating doesn’t apply anymore. You might be getting just 700 psi at the car window after compensating for the wide angle tip and extra distance. Which is good, because you shouldn’t be using any more than 1200 to 1300 psi for cleaning your car. Some pressure washer models feature adjustable pressure, which you can control through the wand or by turning a knob on the control panel.
Selecting the right nozzle
There is a standardized color coding system for pressure washer nozzles. Based on the color of the nozzle, you can tell what angle it is. Higher angles provide a wider fan spread for rinsing and general cleaning work; lower angles restrict the spread for a tiny but powerful jet of water.
Red tip Nozzle shoots a concentrated 0° water jet.
- Yellow — 15° wide spread of water at the tip
- Green — 25°
- White — 40°
- Black — 65°
Use the red tip nozzle to remove caked-on mud from construction equipment, and for stripping rust from metal surfaces. It can also be used at an angle to clean high strength concrete. A turbo nozzle provides the force of a red tip but with much higher area coverage for faster cleaning. Cleaning with a red nozzle is not recommended, since it is unsafe to use on most materials due to the extremely high pressure. Besides, with that tiny jet of water it will take ages to clean anything.
The 15° or yellow tip nozzle can be used for paint prep or to remove mud and dirt from 4 x 4s.
For general cleaning and gentle lifting, use the 25° green tip nozzle. This nozzle is perfect for patio furniture, driveways, and wooden decks.
Cars and windows can be cleaned with the white tip 40° nozzle. It is also great for rinsing, after you’ve used the 25° nozzle to loosen up the dirt.
The black tip 65° nozzle is also known as the soaping nozzle. Its larger opening decreases the velocity at the end of the pipe, and increases pressure within the hose. This added pressure pulls detergent into the line. szUse detergent on your driveway or windows for an easier clean. You won’t require as much pressure or time if you spray a surface with detergent prior to cleaning it. Use detergent recommended by your pressure washer manufacturer, you can’t just pour a bottle of dish soap into its detergent tank.