A portable steam cleaner eliminates the need for the heavy, self-contained machine that houses the water pump, vacuum system, solution tank, and wastewater recovery tank. It moves the vacuum system and recovery tank from the self-contained unit to a module that the technician wears on his back. The water pump itself becomes a separate unit that attaches to any external tank of water at the job site, such as a bathtub. This external tank serves as the solution tank. Because the portable steam cleaner breaks the machine into small, manageable modules, a technician can easily transport the equipment to a job site. With the smaller steam cleaner, the technician has a great degree of flexibility, so he can maneuver the steam cleaner with ease and efficiency. Finally, because the recovery tank rests on the technician's back, he can effortlessly drain the tank simply by opening a valve.