A cold-water pressure cleaner has only one mechanical system, a pump that provides water power. This cleaner is the least complex, least expensive and most popular of pressure cleaners. However, cold-water pressure cleaners require the most amount of water and typically take the most time to use because they rely only on water pressure and not soap or heat as hot and steam pressure washers do. For these reasons, they are commonly used for small jobs such as washing cars or decks. For larger, dirtier jobs, the cold-water pressure cleaner may not work as well as a cleaner that can use heat and soap.
Hot-Water Pressure Cleaners
A hot-water pressure cleaner adds heat and soap to the cleaning process. A raised temperature allows you to use less water and time but get the same or a superior result to that of a cold-water cleaner. The heat helps break down the bond between a stain and a surface. Therefore, a hot-water pressure cleaner is often used to clean grease or oil from a driveway.
Steam cleaners are similar to hot-water cleaners in that they are both powered by liquids and have pumping, electrical and soap systems. However, the steam cleaner uses much lower pressures and flow rates and much higher temperatures. The water in a steam cleaner is heated to more than 300 degrees Fahrenheit. This allows the water to stay in liquid form until it comes in contact with the air. When it does, it immediately vaporizes, drops to its open-air boiling point and expands. The drop in temperature and expansion enable the water to infiltrate the surface and extract the dirt. The high temperature allows the steam cleaner to work better than other pressure cleaners, but it can be harmful to some surfaces, such as vinyl siding on a house.