Selecting a Pressure Washer

How to select pressure washer

Cleaning Units

Cleaning units gives the customer a measure of unit performance (efficiency) to compare one unit to another. Cleaning units is calculated by multiplying PSI and GPM.


3200 PSI x 2.4 GPM = 7680 Cleaning Units VS. 4000 PSI x 3.5 GPM = 14000 Cleaning Units.

how to chose a pressure washer

The 4000 PSI unit cleans 50% faster than the 3200 PSI unit. Not better, but faster. Cleaning units do not determine quality of the unit. Quality is determined by the type of pump and the components of the pump.


Most commonly found on industrial models, a belt driven pump is ideal for cleaning applications requiring 20+ hours of use per week. The belt connecting the engine or motor with the high-pressure pump dissipates the heat and vibration, minimizes the wear and thus the repair on key components, and extends the life of the pump by reducing the RPM demand.


For applications not requiring more than 20 hours of use per week, direct driven pumps are more commonly used. The pump is directly coupled to the engine or motor causing the pump to spin twice as fast as the belt drive models. Although these models are not recommended for heavy, consistent usage they are a lower cost alternative to more expensive, belt driven models.

Is Time a Factor?

A heavy duty pressure washer can cut cleaning times in half. Shorter cleaning time means less labor, which equals more productivity.

how to choose a pressure washer selecting best pressure washer

Cold Water Pressure Washers vs. Hot Water Pressure Washers

When choosing a pressure washer, your application will play a major factor in whether you need a Hot or Cold water pressure washer. Cold water pressure washers are ideal for removing dirt and mud from most any surface; decks, siding, concrete, etc. For more cleaning power there are accessories available that work with a cold water pressure washer, increasing cleaning power and decreasing cleaning time.

However, to clean any surface that needs to be degreased, hot water is a must. Cold water pressure washers cannot remove grease and oil effectively. You wouldn’t think of washing your greasy hands with cold water and the same principle applies to power washing. Also, if you operate cold water equipment more than a few hours a week, you should closely consider the labor savings that could be realized by switching to a hot water pressure washer.