A One-Stop Guide to Your Hot Tub's Pressure Switch

A One-Stop Guide to Your Hot Tub's Pressure Switch

by Mark Zalewski

As the owner of a hot tub, it is important that you possess at least a rudimentary understanding of how your system works. Otherwise you will stand a greater chance of dealing with unexpected complications down the line. The best place to begin is to build up a knowledge of the various components that are required to keep a hut tub running strong. If you would like to learn more about one of the most important safety components at work in your hot tub, read on. This guide will provide a useful introduction to the role played by the pressure switch.

An Overview Of Hot Tub Mechanics

Before diving into the mechanics of the pressure switch, it will be helpful to understand the bigger picture about how a hot tub works. In order to work properly, and to provide safe and effective results, your hot tub utilizes a sophisticated system whose principal components are the circulation pump, the suction lines, the filter, and the heater: the circulation pump, the jet pump, the heater, and the filter. The job of the circulation pump is to draw water out of the hot tub. It then passes through the suction lines to the filter, which acts to remove any debris or impurities. This ensures that the water remains clean, while also protecting delicate internal components from becoming clogged or worn down by friction.

Having past through the filter, the water moves on into the heater. There it is brought up to the temperature specified on your control panel. In most cases this is accomplished through electrically powered heating elements, though a minority of hot tub owners have heaters that utilize natural gas. Once the water has reached the desired temperature, it is carried back to the hot tub by means of a return line. Smaller lines then deliver heated water to each of the tub’s jets, where it is mixed with an air stream delivered by means of the blower motor, thus generating pleasant bubbles.

The Pressure Switch

The pressure switch is part of your hot tub heater’s built-in safety system. A fine example of a common one is the Balboa 30408 pressure switch. It’s job is to prevent scalding, melt-downs, or even heater burnout caused by excessively hot water. Here it is important to make a distinction between the pressure switch and the related safety device known as the overheat high-limit switch. Both act to protect you and your hot tub from the same problem. However, they do so from two different angles.

As its name would suggest, the overheat high-limit switch directly monitors the temperature of the water inside of your hot tub’s heater. Should the temperature become too high--generally anything above 120 degrees Fahrenheit. Temperatures above that threshold are capable of causing serious burns to anyone inside of the hot tub, while also potentially damaging or even melting components within the circulation system.

The pressure switch is ultimately responsible for preventing the same problems from occurring. Rather than monitoring the water temperature, however, its job is to regulate the pressure inside of the circulation system. When the pump is working properly, the rate of flowing water acts to keep the pressure system at a certain level. But if the pump ceases to function, or if some obstruction restricts the flow, water will no longer be able to flow through the system. This will cause a corresponding drop in system pressure.

Excessively low system pressure will lead to the same problems as overheating. Because the water inside of the heater is not able to flow out into the hot tub, its temperature will continue to rise, eventually leading to extensive damage. The pressure switch’s job is to prevent this from happening. So long the system pressure remains above a certain threshold the pressure switch will allow the heater to continue running. But if the pressure should drop below that critical level, the pressure switch will automatically trigger the heater to shut down.