The Difference Between Cold Water and Hot Water Pressure Washers

Cold water pressure washers are much less expensive than hot water pressure washers, but is there a good enough reason?

While cold water pressure washers do a fine job of cleaning cars, removing dirt and cobwebs from siding, and even erasing the majority of scummy-looking build-up on your walkways, there's a noticeable difference when using a hot water pressure washer.

A great analogy to use in explaining the difference is dish washing. Let's assume you just ate pot pie for dinner last night, and your dirty plates have been sitting in the sink for nearly 24 hours. When you finally work up the motivation to dive in and clean those nasty things, do you use hot water or cold water?

Hot water, as you may remember from high-school science class, contains faster-moving molecules. As temperature rises, molecules kick into overdrive and move away from one another.

Cold water contains much slower moving molecules, and the molecules tend to stick closer together.

Therefor, the hot water molecules are more effective because they move faster and agitate the filth, separating it from the surface. Hot water pressure washers, for that reason, work much better.

So now that you know a hot water pressure washer is better, is that why they're so much more expensive?

Not exactly. Hot water pressure washers require a heating mechanism, which increases the manufacturing cost. The burning mechanism increases the cost as well as the copper tubing used to run the water over the heat.

More materials, more time, and more design drive up the price of these highly sought-after machines.

So depending on whether you're looking for a highly effective cleaning machine or a lighter-duty car washing and cobweb removal machine, you may want to consider spending the extra bucks.