Hot tub and pool at sunset

Most of the time, you won’t give your hot tub’s plumbing a second thought. As it hums away in the background, you’ll be focused on relaxing and enjoying yourself, not figuring out how the water gets pushed through the jets.

Every once in a while, though, you may find yourself wondering just how your hot tub creates such a soothing, tranquil environment.

Read on to discover what goes on behind the curtain to make your hot tub sessions happen.

Hot Tub Plumbing Basics

Let’s start with an empty hot tub. Here’s what happens next once you fill it with water.

1. Suction Line and Skimmer

First, the hot tub’s suction line will begin to suck in water. Meanwhile, the skimmer will start removing debris like leaves, insects and the like.

Both the suction line and the skimmer will send water to the pump.

2. Pump and Filter

Next, the water collected by the suction line and skimmer makes its way to the pump. There, the pump pushes the water toward the filter.

As the water passes through the filter, any small contaminants such as dust and dirt particles are removed.

3. Heater and Manifolds

The newly filtered water is now sent to heater. Here, the heater will — you guessed it — use its heating element to make the water nice and toasty.

Once heated, the water will flow through the hot return line and into the manifolds. In simple terms, manifolds are water diverters. They accept the water from a single source, and then divert it to many different locations.

4. Jets

The clean, hot water then flows from the manifolds to the hot tub’s jets via a number of flexible PVC pipes.

Finally, the water is pushed out of the jets and reaches you.

Other Elements of Hot Tub Plumbing

The four steps described above are foundational to modern hot tub plumbing, and hold true for nearly every hot tub on the market.

Depending on the individual hot tub, though, there may be some other elements that come into play.

For example:

Air Controls

In addition to water, hot tubs can also draw in air and expel them through the jets, creating a pleasant bubbly effect.

This can be accomplished with simple air control valves, and may also be assisted by an electric air injector or blower.


Of course, no hot tub water is safe to relax in without the help of an effective sanitizer.

Traditionally, this means the use of either chlorine or bromine. In that case, you’ll simply sanitize your water by adding those chemicals in liquid, powder or tablet form.

Alternative sanitizers, however, add a few extra steps to the plumbing process (although none of them involve an extra effort on your part!).

With ozonators, for example, the water is sent to the ozonator once it’s been filtered and heated. In the ozonator, bacteria-busting ozone molecules are added to the water.

The same is typically true for salt water sanitation systems. Once the water is clean and hot, it’s sent to the salt cell to be sanitized before being pushed into the hot tub.

To learn more about the best alternative hot tub sanitizers, click here.

Take Care of Your Hot Tub’s Plumbing

To you, your hot tub’s plumbing system may seem inconsequential. Without it, though, your hot tub would be nothing more than a large bucket of cold water.

So, it’s important that you always take good care of your spa’s plumbing. By doing so, you’ll ensure that your hot tub provides you and your family with years of relaxation and fun.

Check out these articles to find out how you can keep your hot tub’s plumbing system clean, maintained and running smoothly: