How a Hot Tub Works Most everyone has enjoyed the wonderful sensation of relaxing in a hot tub or spa. If you haven’t, you owe it to yourself to give warm water therapy a try. Here’s a primer on how the various components of a portable hot tub combine to create a luxurious experience. Shell The hot tub surface, or shell, is typically made of acrylic or another weather and chemical resistant thermoplastic. The shell is reinforced or supported with either fiberglass backing, high density polyurethane foam or some combination of the two to enable the hot tub to withstand the weight of the equipment, water and bathers. Cabinet  Traditionally wood, now weather resistant polymer, today’s cabinets are both attractive and easy to maintain. The cabinet houses all plumbing, pumps, heaters, etc., making the unit “self-contained” and “portable.” Pumps  One or more pumps are used to circulate the water in and out of the hot tub. Pumps force a large volume of water through tiny jet nozzles on the surface of the hot tub, creating high pressure streams. The number of pumps is proportional to the size of the unit, the number of jets and the degree of therapy delivered. Jets The water stream generated through the pump action pulls air through each jet with Venturi action. The air and water mix, creating bubbles that caress the body as they break against the skin to create a pleasurable experience that alleviates pain and muscle soreness. Heater  The heater operates like a home hot water tank. As the water circulates through the hot tub, it is warmed by the heating element in the spa cabinet. Digital Control Pad  The control pad allows bathers to change water temperature from inside or outside the hot tub. The water in a hot tub should never exceed 104 degrees Fahrenheit, which is the maximum temperature sanctioned by the Consumer Product Safety Commission. If children or adult bathers are using the tub for prolonged periods of time, the water temperature should be kept at 98 or 99 degrees. Sanitation system The hot tub’s filter plays a role in keeping the water clean and clear, as do the chemicals that are added on a routine basis. For detailed information about maintaining healthy water, click over to “Hot Tub Chemicals 101” under the “Already Own?” section. All these components working together produce a great hot tub experience. Learn more about the benefits of hot tub ownership.