# How to Use a Pressure Washer: 8 Steps for Gas, Electric and Hot Water > A step-by-step commercial guide to using a pressure washer: setup order, gas, electric and hot-water start-up, soap and degreaser application, cleaning technique, safe shutdown and wash-water rules. - **URL:** https://janitori.com/blogs/equipment-guides/how-to-use-a-pressure-washer **In this guide** - [Set up and start, step by step](#steps) - [Gas, electric and hot water](#gas-electric) - [Using soap](#soap) - [Cleaning technique](#technique) - [Shutting down](#shutdown) - [Safety and wash water](#safety) - [FAQ](#faq) To use a pressure washer, connect the water supply, connect the high-pressure hose, gun and wand, fit the right nozzle, turn the water on, and only then start the machine. The order matters because a pump that runs without water can be damaged. This guide follows the published procedures from Imperial Brady and Greenworks, then adds what a commercial crew needs: hot-water machine start-up, soap injection, floor-level technique and a shutdown routine you can hand to a new hire. **Key takeaways** - Turn the water supply on and confirm flow before you start the engine or motor, because running the pump dry can damage it. Forgetting the tap is the most common reason a new machine seems dead. - Use a true high-pressure hose between the pump outlet and the gun, never a garden hose. A garden hose is not built for the pressure and will tear, so keep every connection snug. - Soap only flows through the low-pressure soap tip. Switch to a clean-water tip to rinse, and clean from the top down in overlapping strokes so dirty water runs away from finished work. - Shut down in order: release the trigger, lock it, cut the water, squeeze the trigger to bleed pressure, then disconnect hoses. Never point the gun at skin, since a high-pressure injury can look minor at first. ## How Do You Set Up and Start a Pressure Washer, Step by Step? Set up from the water side to the spray side, start the machine last, and test a small area before you clean. Imperial Brady breaks the process into nine steps and Greenworks uses the same nine. - **Prepare the power source.** Plug a corded electric washer into an outlet that matches its voltage. For a gas machine, add the fuel your manual specifies. If the machine has a hot-water boiler, fill the boiler tank with diesel, not gasoline. - **Connect the water supply.** Find the water inlet, which is the only place a garden hose attaches, and tighten the hose on. A loose connection causes low pressure and leaks. - **Connect the pump outlet to the trigger gun.** Use a high-pressure hose, which is thicker and threaded differently from a garden hose and built to take pressure and heat. If you use a soap injector, fit it on the pump outlet first and run the high-pressure hose from the injector to the gun. - **Attach the wand.** Slide the wand into the gun, push down and twist (some brands screw in) and tug to confirm it is locked. - **Choose and fit the nozzle.** Pull back the collar on the wand, insert the tip, release the collar and tug to confirm it is locked. Wider angles clean faster; narrower angles dig deeper. Our [pressure washer nozzle chart](/blogs/equipment-guides/pressure-washer-nozzle-chart) shows the color and size for each job. - **Turn the water on.** Open the supply fully and let water flow before you power anything. Greenworks says to prime the pump so it is not run dry. - **Start the machine.** Press the power switch on an electric unit. On a gas unit, open the fuel valve, switch on, set the choke to full start, pull the cord and move the choke to run once it fires. Check oil first. - **Start cleaning.** Squeeze the trigger and begin with a test patch. For a crew, print the sequence and keep it with the machine so every operator does it in the same order. ## Does a Gas, Electric or Hot-Water Pressure Washer Start Differently? Only the power-up step changes. Water connections, hoses, wand and nozzle are the same, and the main differences are the fuel for a gas engine and the separate boiler on a hot-water machine. Imperial Brady notes that on a hot-water machine the boiler has its own start button or switch, and it needs about 5 minutes to warm up before you clean. Greenworks gives the same 5-minute figure. Electric units skip the fuel and choke steps entirely. Machines in our range that cover the three types include the electric [Pressure-Pro Eagle EE2015G](/products/pressure-pro-eagle-ee2015g-electric-cold-water-direct-drive-pressure-washer-1500-psi-2-0-gpm-115v-1ph-18a-gp-pump), the gas-powered [Pressure-Pro Eagle II E3027HC](/products/pressure-pro-eagle-ii-e3027hc-20-cold-water-gas-direct-drive-pressure-washer-2700-psi-3-0-gpm-honda-gx200-cat-pump) and the hot-water [Pressure-Pro Hot Shot 4012-10C](/products/pressure-pro-hot-shot-4012-10c-hot-water-gas-pressure-washer-4000-psi-4-0-gpm-honda-gx390-cat-pump). Always follow your own model's manual for fuel, oil and start-up. ## How Do You Use Soap or Degreaser With a Pressure Washer? Apply soap through the low-pressure soap tip, let it work for a few minutes without drying, then switch to a clean-water tip and rinse. Chemistry only draws through a downstream injector when the wide soap tip is installed. Greenworks suggests pre-treating built-up dirt, oil or grime with a detergent or degreaser before you wash. For greasy concrete, loading docks and dumpster pads, a degreaser built for pressure washers does the heavy work so the water only has to rinse. Our guide to [pressure washer soap vs degreaser](/blogs/equipment-guides/pressure-washer-soap-vs-degreaser) covers injector types and a mixing chart. **Run it with JANITORI chemistry** [Degreaser MAX No.72](/products/degreaser-max-janitori-no-72) The pressure washer degreaser. Its label says it is ready to spray, mop or apply by pressure washer once mixed, it rinses residue-free with hot or cold water, and it contains no phosphates, petroleum solvents or VOCs. One 3.6 L jug makes about 720 L of working solution at 1:200. ## What Is the Right Cleaning Technique? Work top to bottom in overlapping strokes, keep the wand moving, and start with a wide-angle tip from a safe distance before you move closer. Holding the spray in one spot can mark the surface. - **Grid pattern.** Greenworks recommends starting at the top and working down in overlapping strokes. - **Distance and angle.** Greenworks suggests holding the nozzle about 4 inches from the surface for best results on tough surfaces, with a wide spray to clean quickly and a narrow spray to dig deeper. Back off on softer surfaces and test a hidden patch first. - **Match the machine to the surface.** Greenworks says vinyl siding and brick can take 2,500 to 3,000 PSI, while aluminum siding, stucco and softer woods call for about 1,200 to 1,500 PSI. For commercial work, our [pressure washer PSI chart](/blogs/equipment-guides/what-is-a-good-pressure-washer-psi) lists PSI and GPM by job. - **Do not use it on composite decking**, which Greenworks says is easily damaged. ## How Do You Shut Down a Pressure Washer Safely? Release the trigger and engage the safety lock, turn off the water, squeeze the trigger to bleed the remaining pressure, then disconnect the hoses. Store the machine in a dry indoor spot. - Release the trigger and engage the lock. - Turn off the engine or motor and the water supply. - Squeeze the trigger to release trapped pressure, then lock it again. - Disconnect the hoses, gun and wand and let them drain. - Store dry and indoors. If the unit will sit through a freeze, follow our [winterizing steps](/blogs/equipment-guides/how-to-winterize-a-pressure-washer). ## What Safety Rules and Wash-Water Rules Apply? Treat the spray like a tool that can injure, wear eye and foot protection, and keep wash water out of storm drains and off walking surfaces. These rules apply to every operator on every job. - **Never point the gun at skin.** A case report on high-pressure water injection injuries notes that early symptoms can be minimal even though the injury is serious ([PMC, high-pressure water injection injury](https://pmc.ncbi.nlm.nih.gov/articles/PMC2657237/)). Any injection needs emergency care. - **Wear goggles, boots and gloves, and never wash from a ladder.** Greenworks lists these as basic safety gear and rules, and also advises keeping spray away from windows, lights and power lines. - **Use a GFCI on electric units.** The CPSC has recalled electric pressure washers sold without an integral ground-fault circuit-interrupter because of shock and electrocution risk ([CPSC recall notice](https://www.cpsc.gov/Recalls/2026/Workbless-Pressure-Washers-Recalled-Due-to-Risk-of-Serious-Injury-or-Death-from-Shock-and-Electrocution-Hazards)). - **Control the water.** Where wet processes are used, OSHA requires drainage to be maintained and, to the extent feasible, dry standing places such as mats or platforms ([OSHA 29 CFR 1910.22](https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.22)). EPA stormwater guidance also advises keeping vehicle and equipment wash water out of the storm system ([EPA stormwater BMP](https://www.epa.gov/system/files/documents/2023-01/bmp-vehicle-maintenance-and-washing.pdf)). ## Frequently Asked Questions ## Do I turn the water on before starting the pressure washer? Yes. Open the water supply and confirm flow before you start the engine or motor. Greenworks says to prime the pump with water first, because running a pressure washer pump dry can damage it. ## Can I use a garden hose between the pump and the gun? No. Use a high-pressure hose from the pump outlet to the gun. Imperial Brady notes a garden hose will not stand up to the pressure and tears. A garden hose is for the water inlet only. ## How long does a hot-water pressure washer take to warm up? About 5 minutes after you start the boiler, according to both Imperial Brady and Greenworks. The boiler has its own start switch, and its fuel tank takes diesel, not gasoline. ## How do I get soap to come out of my pressure washer? Fit the low-pressure soap tip and make sure the injector is connected between the pump and the gun. Soap draws through only at low pressure, so switch to a clean-water tip when you want to rinse. ## What should I do first if my pressure washer will not spray? Check the basics: is the water tap on, are the hose connections tight and is the nozzle locked in. Imperial Brady notes that forgetting to turn the water on is a common cause when no water comes out. ## Related Guides - [Pressure Washer Nozzle Chart: Colors, Angles and Tip Sizes](/blogs/equipment-guides/pressure-washer-nozzle-chart) - [Pressure Washer Soap vs Degreaser: What to Use and How to Apply It](/blogs/equipment-guides/pressure-washer-soap-vs-degreaser) - [What Is a Good Pressure Washer PSI? A Commercial Job Chart With GPM](/blogs/equipment-guides/what-is-a-good-pressure-washer-psi) - [How to Winterize a Pressure Washer](/blogs/equipment-guides/how-to-winterize-a-pressure-washer) - [Pressure Washer vs Power Washer: What Is the Difference?](/blogs/equipment-guides/pressure-washer-vs-power-washer) [Shop Pressure Washers](/collections/pressure-washers) [Shop Degreaser MAX No.72](/products/degreaser-max-janitori-no-72)