Archive for the ‘Cleaning Equipment’ Category

Jan
03
Pressure Washing Units | Flow vs Pressure
Filed under (Cleaning Equipment) by ftd09 @ 11:20 pm

Trying to figure out which pressure washing unit is best for professional washing can be difficult but here are a few key guidelines to ponder. The biggest misconception with washing professionally or as a do it yourselfer is that the pressure does the cleaning. This is somewhat true but it’s not as important as the flow of the pressure washer. Pressure is measured in pounds per square inch (PSI) and can definitely make a difference on concrete and other surfaces that you can get aggressive with.

The flow is measured in gallons per minute (GPM). The GPM of a pressure washer is the biggest factor as to how fast or efficient it will clean. For example, if the pressures are identical, an 8 GPM pressure washer will clean twice as fast as a smaller 4 GPM unit. Professional contractors and anyone who is experienced in washing will turn down the pressure on vinyl siding, wood, and other surfaces that are easily damaged. So it takes the pressure out of the picture completely.

The set back is that the more GPM a unit is the more expensive it is. Rarely does a pressure washing unit exceed 4000-5000 PSI with 3000 being average. Even smaller consumer grade pressure washers will be 2000 PSI and up so the pressure is really not the concern when cleaning and especially cleaning for a living, it’s the flow or gallons per minute where you will find all your efficiency.

It’s the same concept if you only turn your sink faucet on half way to rinse a dinner plate. It can take a while and when you turn it all the way on it rinses much faster despite that the pressure is relatively the same. The more flow the better for cleaning. When coupled with the right cleaners to break down and emulsify dirt, mold, and mildew it is a hard combination to beat. It will always work better than high pressure and just water. But because it’s called a “pressure washer” so many people fall into the trap of thinking it’s all about blasting the heck out of stuff. Bottom line is that method will risk damage to the surface and won’t be as effective as more flow and chemicals.