The question "When should a hot water pressure washer be used?" usually revolves around the type of cleaning job to be done. If you're in the market for one of these units, be prepared for a seemingly endless choice from which to select. Generally, the first thing to keep in mind when deciding whether or not to go with hot water is if it's the right machine for what needs to be accomplished.
Many experts feel that a hot water pressure washer gives you the most versatility when it comes to more than a few cleaning applications. Do you need something to blast away built-up or recalcitrant grease? Then a hot water unit combined with the right degreasing agent can make lifting them off and washing them away a relative snap.
Let's be honest, though: Hot water units are definitely more expensive than a straight up cold water pressure washer, and that has to be factored into the possible purchase decision. However, most every industry expert agrees that hot water pressure washers clean faster and more thoroughly in comparison to their cold water brethren. Faster cleaning means less water used, and this can be crucial in certain cleaning applications.
In a pressure washer that uses hot water, there are several differences than in a mainline cold water unit. One is that there's a boiler that heats up water in the washer unit. These boilers come in different sizes and metals. Hot water pressure washers also use various fuel sources to heat the boiler. The preferred source is propane, but gas, diesel or electric heater units are also readily at hand.
Usually, the hot water pressure washer that's offered in any geographic region will depend upon the ready availability of specific fuels. If the area doesn't really rely on propane, then chances are you'll see more diesel or electric heater-type units. In any event, the better pressure washers will come with stainless steel boilers and heater coils.
Keep in mind that larger cleaning jobs will require a washer that's capable of performing continuous cleaning operations. Units such as these come equipped with the ability to heat the water as soon as it's run through the washer, so there's no waiting around for a new load of water to be heated up as it's drawn into the boiler.
Besides all the above, another measure of performance that a hot water pressure washer is judged by relates to the unit's flow rate and the water pressure it can build. Pressure is normally measured in PSI (pounds per square inch), and some of these washers can hit well over 2000 PSI.
At these amounts, it's very easy to damage certain soft surfaces, peel paint off surfaces or gouge wooden fences or aluminum or vinyl siding so be cautious when using such a machine. Also, don't use one of these high pressure units on delicate flooring materials. Scratches, gouges and chips may quickly develop.
Flow rate in any pressure water is a measure that tells you how much water can be put out at the rated pressure of the unit. In industrial pressure washer units, expect to see flow rates of several or more gallons per minute.
