Hot Tub Glossary

Aerator: Air blower that enables the hot tub user to determine the amount of air that is introduced into the water through the jets. It allows water massage from gentle to full throttle.

Brake (or start-up) horsepower: the force required to start the pump; more force is required to start the pump than to keep it operating continuously.

Circulation pump: A small pump used in combination with a one-speed pump. It continuously circulates the spa water and generates that is distributed back into the spa.

Continuous-duty horsepower: the flow of pressure that keeps the pump running. It required less energy to operate the pump continuously than to start it.

Cover: Should be composed of high-density foam for structural soundness, an R-value (measure of insulation) of 12 or higher and a long apron (or side flaps) to ensure heat conservation. It should also have a locking mechanism and a UL (Underwriters Laboratories Inc.) or ASTM (American Society for Testing and Materials) International listing. The spa cover locks in heat, chemicals and prevents children and small animals from gaining access to the water.

Diverter Valve: Valve that controls the flow of water to multiple sections of the spa; used in spas that have a only one main pump because all jets cannot run simultaneously

Filter: Usually a cartridge that traps particles and keeps the spa water clean. Filters need to be replaced periodically.

GFCI: Ground Fault Circuit Interrupt. Type of circuit breaker used for controlling electrical power to the spa.

Heater: Controls the temperature in your spa, which should not be any higher than 104 degrees F. It's crucial that you maintain proper water balance to prevent corrosion to the heater.

Hydrotherapy: The process by which warm water or hot tub therapy can help with many ailments, including muscle pain, arthritis, insomnia and reduction of stress.

Jets: Manipulate the air from the pumps and disperse it into the water.

One-speed pump: A spa's main pump. Because it only has one speed, this pump supplies water to the jets while the circulation pump circulates the spa water. Spas with more than one main pump can run all jets simultaneously; spas with only one main pump have a diverter valve that diverts water to different seats at different times.

Ozonator (ozone generator): A device that disperses ozone into the water and assists in sanitizing the spa water.

Ozone: An oxidizer added to the water via an ozonator; it also assists in sanitizing but does retain little residual so must be used in conjunction with another sanitizer

Pumps: The pumps generate the air that shoots through the various jet configurations.

Shell: Interior surface of the hot tub, usually made of acrylic and available in many colors.

Skirt/cabinet: The exterior spa cabinet, typically made of wood or simulated wood and available in many stains. It protects the hot tub shell and its components

Thermal blanket: A thin piece of plastic with air bubbles that holds in heat; used in conjunction with a standard foam safety cover

Two-speed pump: A spa's main pump. Because it has two speeds, this pump supplies water to the jets and pump circulates the water. Spas with more than one main pump can run all jets simultaneously; spas with only one main pump have a diverter valve that diverts water to different seats at different times.