Picture this: You’ve just finished devouring a plate of spaghetti with rich, oily marinara sauce. Now, it’s time to clean up. You fill one sink with cold water and another with hot water. Even with a heavy dose of dish soap in the cold sink, the grease clings stubbornly to the plates. Meanwhile, in the hot water sink, the sauce dissolves almost instantly, leaving you with squeaky-clean dishes in no time.
This is the same principle that applies to pressure washing—and why hot water pressure washers exist.
But when should you use hot water, and when is cold water enough? Is it worth the extra cost? Let’s break it down.
Cold Water Pressure Washers: The Workhorse of Cleaning
How They Work
- Cold water pressure washers rely on high pressure to blast away dirt, mud, and debris.
- They’re effective on non-greasy substances like dust, loose dirt, sand, and mildew.
Best For:
Washing cars, patios, and siding
Blasting off loose dirt and debris
Routine cleaning of concrete, sidewalks, and driveways
General household and commercial cleaning
When Cold Water Struggles:
- Grease and oil stains laugh in the face of cold water.
- Industrial messes from mechanic shops, restaurants, or factories often require something stronger.
Hot Water Pressure Washers: The Heavy-Duty Cleaner
How They Work
- These machines heat water (often up to 180°F+) before it exits the spray nozzle.
- The combination of heat, water pressure, and detergent makes cleaning greasy surfaces faster and more effective.
Best For:
Oil and grease removal – Think garage floors, engine parts, heavy equipment and restaurant exhausts.
Heavy-duty industrial cleaning – Factories, construction sites, and food processing plants.
Sanitization – Hot water kills bacteria better than cold water, making it useful for farm equipment, dairy farms, poultry farms, medical facilities, and food production areas.
Downsides of Hot Water Pressure Washers:
- More expensive – Up to 3 times the cost of a cold water machine, they require a heating system, increasing initial cost and fuel consumption.
- Bulkier and heavier – Hot water units are larger and less portable.
- Overkill for light-duty jobs – Cold water is often good enough for dirt and dust.
How Does a Hot Water Pressure Washer Heat the Water?
There are three main ways water is heated in a pressure washer:
1️⃣ Electric Heating Elements – They use 3 phase power to electricity heat the water with submerged heating elements, warming the water as it flows through the holding tank.
2️⃣ Diesel/Kerosene Burners – Found in industrial-grade pressure washers, these burners heat water efficiently for high-powered cleaning.
3️⃣ Propane/Natural Gas Systems – Used for stationary hot water units, often in commercial settings.
Do I Need Steam for Cleaning?
Steam pressure washers take it one step further. They use lower pressure but heat water above 300°F to turn the water into steam. This allows for powerful cleaning without excessive water runoff, making them ideal for situations where water control is critical.
Best for:
Removing grease, gum, and bacteria
Disinfecting surfaces in food processing plants
Melting ice or removing stubborn oil buildup
Cleaning inside manufacturing facilities where drains are limited or where you need to avoid excess water runoff
Cleaning engine compartments where sensitive electronics could be damaged by water
Not for everyday cleaning – Steam is overkill for washing a patio, driveway, or car.
If you need deep cleaning in a controlled environment without creating a water mess, steam is the best solution.