How to Power Wash a House With the Right PSI

Choose the correct power washer for the job. Basic washing for all house types such as vinyl, brick or wood can withstand washing from a power washer with a PSI of 1,500 to 1,800 without fear of causing damage to the house, according to online resource House Painting Info.com.

Use a power washer with no more than 2,500 PSI for heavy cleaning of brick or concrete surfaces, and to remove loose paint from wood surfaces. Insert a 15-degree spray tip in the spray nozzle for these purposes only. Hold the spray gun at a sharp angle so that the spray will work like a scraper to remove paint. Do not use this setting or nozzle for general cleaning of wood or vinyl surfaces.

Move flowerpots, furniture, wall plaques, wind chimes, or anything that is in the path of the power washer. Check to make sure that all windows are closed. Put on the safety glasses before going any further. It is too easy to forget to put them on. Safety glasses will protect your eyes from flying dirt.

Connect the garden hose to the outside tap, and to the water intake valve on the power washer, and turn on the water. Do not try to start the power washer until you have completed this step, because dry starting a power washer will burn up the motor.

Squeeze the trigger on the wand until a stream of water comes out. Doing this will pull water through the pump, and release pressure. When all steps are completed, you can start the power washer.

Squeeze the trigger and adjust the spray width on the tip of the wand to a medium-width spray pattern, or use a 25-degree nozzle tip if the wand tip is not adjustable on the model you are using. Begin washing the house from the bottom and work your way up. Move the wand from side to side while you are washing, and keep the tip of the wand at least 3 feet back from the surface of the house when using a 2,500 PSI power washer, advises Ultimate Washer. Wash a 4- by 8-foot section at a time and then rinse the dirt off from the top down. Continue this pattern for the entire house.

Spray at a sharp angle away from light fixtures, windows, doors, and electrical outlets. A power washer is strong enough to break glass, and pass water around light and electrical fixtures into the wiring.

Attach a wand extender to the power washer to reach upper levels on the house. It is not safe to work from a ladder. The blast from the power washer when you pull the trigger is enough to knock you off balance, Ultimate Washer notes.