Can You Run Hot Water Through a Pressure Washer?

Is it possible to run hot water through a pressure washer? No, you cannot run hot water through a pressure washer which is designated as a cold-water unit. Doing so could cause the unit to malfunction by melting the seals inside and overheating it. A cold-water unit can deal with temperatures up to 150 Fahrenheit, but there are hot water pressure heaters that are better suited to higher temperatures.

Pressure washers are fabulous for cleaning all kinds of grime, caked-on dirt, and even paint off surfaces of all kinds. But on some occasions, like times in grease, hot water might be better for cleaning. So, with that in mind, can you run hot water through a pressure washer if you need to?

With this in mind, your cold-water pressure washer might not be able to clean everything you need it to. Is it worth buying a hot water pressure washer then?

Well, let’s discuss it!

High pressured pressure washer using hot water to clean graffiti on street

Related Reading: How Much Water Does A Pressure Washer Use?

What’s The Difference Between Hot Water and Cold Water Pressure Washers?

Cold Water Pressure Units

This may be one of the most important things to establish when deciding whether a hot water pressure washer is worth it: what are you actually buying?

Coldwater pressure washers are the most common kind that people purchase for use at home. This comes with a few benefits, such as being more cost-effective, smaller than their hot water equivalents, and much simpler to use, since they’re meant for the average homeowner to clean their patio with.

They are meant for smaller jobs around the home, but that doesn’t mean they can’t handle bigger jobs if they need to. These units use only the force of pressurized water to get rid of caked-on grime, which means that oil and other stains may be inappropriate for it, but considering its simplicity in both operation and maintenance, it’s no wonder that many prefer these for home use.

Hot Water Pressure Units

Now, whilst most homes will likely own a cold-water pressure washer if they own one at all, that doesn’t mean that a few may not own a hot water one. Considering that they are not only needed to create the pressure but handle the heat, they tend to be much heftier than their cold-water cousins. This can make them problematic to both stores and move around the place for use.

Naturally, this makes them a more niche kind of washer, generally used by industries rather than with domestic use, which makes them more difficult to understand as well. However, if you have a large amount of mess that involves either grease or oil, then there is nothing to do the job quite like a hot water unit.

Related Reading: Pressure Washers Under $200 and Under $300 – Buyer’s Guide

What Are Hot Water Pressure Washers Used For?

 Well, as mentioned, greasy things will need some hot water to melt the grease away in order to clean it properly. Hot water breaks down grime like this at a molecular level, rather than just relying on pressure alone to wash it away so these units do a much better job on these stains and messes. This means that if you work in the food industry at all, such as in catering or a restaurant, then a hot pressure washer is what you’ll need for sure.

Not only will cold water not break down the grease, but it won’t kill all the harmful bacteria and mold and won’t help maintain those strict health and safety standards. If you work in machine maintenance, then you’ll also want a hot water pressure washer to get all that engine grease off properly.

Other than those two industries, a hot water pressure heater isn’t generally necessary for most people. Whether you should get one of these units depends very much on how often you encounter particularly greasy messes in your day-to-day life – is the number of times you find these messes worth a large amount of space one of these units takes up how difficult it can be to move around?

Whilst it will allow for the use of less detergent and faster cleaning, most domestic people won’t need one of these.

What Needs a Cold Water Pressure Washer?

Most things can be washed by a cold-water pressure unit just fine. Coldwater pressure washers have no trouble with washing off caked-on dirt or mud, clearing debris, or stripping paint. This means that for nearly every occasion of domestic use, a cold-water pressure washer will do the trick.

But other industries which need pressure washers can also do their jobs easily with cold water, including:

  • Construction
  • Agricultural
  • Transportation

In short, unless you are specifically relying on the hot water in order to melt grease and kill bacteria in large quantities, then a hot water pressure washer won’t be necessary. But the important thing to remember is that if you find yourself facing grease often, then the amount of money spent on a hot water pressure washer will be less than that of having to continually replace the cold-water unit after breaking it by running hot water through it, so if you keep finding stains that need a little heat, then it’s better to invest.

Related Reading: Can You Use An Air Hose for a Pressure Washer?


In conclusion, you cannot run hot water through a cold-water pressure unit without risking breaking it, but there are hot water pressure washers available if you need them.

However, before investing in a hot water unit, it’s worth considering whether you truly need one; hot water pressure washers are cumbersome and difficult to work, not to mention large to store, unlike cold water pressure units which are designed for more domestic use, but if you face an unusually large amount of messes based on oil or grease, then it is worth investing in one rather than risking your cold unit by running hot water through it.