Many Truck Mount manufacturers advertise extremely high water temperatures to make their system(s) seem more appealing. The fact is, water boils at 212° and begins to produce steam. And I know, we all call it “steam-cleaning” but, the truth is, carpet cleaning is done with extremely hot water and not steam. Steam is a gas, you can’t retain any pressure with steam, you can’t clean carpet with steam and you can do real damage to your equipment and carpet. Most truck mount systems today can produce extreme temperatures or steam if you turn the heat up higher than it should be. If a unit can produce heat at 160° to 200° consistently, then it can do the same or better job as a system that promises to produce 240° or higher. Many manufacturers don’t tell you that you can’t or won’t clean with 240°, but simply attempt to mislead you with overblown numbers. Be a wise shopper by knowing what the specifications should be. After all, even if you could, you wouldn’t wash your clothes in boiling water because over time it would damage the material, just as it will damage carpet fibres, backing and glue. But, you would wash them in hot water. Think about it . . . 2. Pressure between 100psi and 650psi. (Optimum Performance: 600psi) Water pressure forces hot water or hot water and cleaning agent into, over or through the carpet. Too much pressure and you force dirt and cleaning agent through the carpet fibres and backing and into the pad, putting down too much moisture to pull up, extending drying time, introducing malodours and/or possibly causing mildew. Not enough pressure and you can’t penetrate the fibres enough to break the dirt loose. The optimum pressure allows you to penetrate the fibres, mix with and remove the dirt. 3. Vacuum at 15Hg, 240cfm. (Optimum Performance: 15Hg, 240cfm) Vacuum is measured in two ways “lift” and “air flow”. “Lift” Most systems can produce 15Hg of lift. 15Hg stands for 15 inches of mercury. This is how much lift it takes on average to efficiently pull water from ground level or lower, up and into your system recovery tank. If you set your system too low below 15Hg you may not have enough lift for extraction, set it too high above 15Hg and you run the risk of doing damage to your system. “Air Flow” is measured in “cubic feet per minute” and is the amount of vacuum power it takes to clear or pull the water through your wand and vacuum hose and up into to the system

recovery tank with consistent performance. The optimum amount of air flow for single floor wand cleaning is 240cfm. So it only goes to follow that the optimum air flow for dual or two floor wand cleaning is double that or around 480cfm. Rather than use two floor wands, many cleaners prefer to take advantage of the “dual-wand” configured system by having one technician cleaning with a floor wand and another using a furniture or detail tool at the same time, achieving optimum performance at around 380cfm. • Heat Exchange VS Propane Heated Machines Most Truck Mount systems today heat the water one of two ways, “heat exchange” or “propane heat.” “Heat Exchange” Also referred to as “heat exchanger” systems are available in two configurations, “air-to-water” or “water-to-water”. In “air-to-water” systems the water is heated by the truck mount engine exhaust or in the case of a dual or two stage air-to-water heat exchange system, water is first pre-heated by the blower exhaust and then heated for use by engine exhaust. This is accomplished by letting the water flow through a metal (usually stainless steel) tube or coil surrounded by an outer metal tube or shell which is filled with hot engine exhaust (air). There are two things to look for with an air-to-water system. One, the system should have a diverter-valve to allow you to divert the engine exhaust away from the water flow and through the normal engine exhaust path when doing water extractions and not cleaning (using water). Two, a “needle-valve” or available mechanism, that assists in regulating the water temperature to the wand. This is done by adjusting the water flow through the inner heat exchange tube. The more water flow the less heat. The less water flow, the hotter the water coming out of the wand. But, since there is no way to regulate the heat of the exhaust air in the outer tube it is better and safer to be able to divert the hot exhaust air away from the inner water exchange tube when not cleaning. With “water-to-water” systems the water is run

By Haadi