What Is an Air Bath Tub and How Do Air Jets Work?

An air bath tub, sometimes called a bubble tub or a bubbler tub, is a bathtub with a blower that pushes air through small jets in the seat and floor, so the water fills with soft, effervescent bubbles around your body. On an Ella walk-in tub this is the air massage system, and What Are Air Massage Jets on a Walk-In Tub? describes the jets themselves. This page explains how the system works from the button press to the automatic drying cycle, how an air bath differs from a hydro bath, and what that means for filling, using and caring for the tub.

Air Bath Versus Hydro Bath

The two jetted systems on a walk-in tub move different things. A hydro massage pump pulls bath water in and pushes it back out through larger water jets, and an in-line heater on that loop holds the water temperature while the pump runs. An air bath moves only air. A blower under the tub sends air through lines built into the shell and out through many small brass jets, and the bubbles rise through the water and break against your skin. The result is a gentler, all-over sensation, which is why air massage is described as the softer counterpart to hydro massage.

On Ella tubs the air jets sit in three groups: upper jets in the seat and backrest, bidet jets at the base of the seat, and lower jets in the footwell floor. They are brass because you sit and stand on them. Air massage is offered as part of a therapy package on most Ella families, including the stainless-door, outward-swing, Transfer, two-seat and LayDown tubs. The Standard, Standard60, Zen, Zen60 and Flow are hydro-only platforms with no air jets. The Deluxe ships with a fixed Air plus Hydro package, and the Shak and Big4One ship with digital air massage alongside their dual hydro pumps. Because the jets and lines are molded into the shell at the factory, an air system cannot be added to a tub later, so the choice is made at order time with your Ella dealer or the team at (800) 480-6850.

How the Air Jets Work, from Button to Bubbles

Ella tubs come with a choice of deck controls, either on and off push buttons or a digital touchpad, and the second video on this page shows both in use. With push controls, pressing the Air button sends a puff of air through a small hose to the control box under the tub, which starts the blower. The button cycles through the speeds in a fixed order:

1. First press: high speed.
2. Second press: medium speed.
3. Third press: low speed.
4. Fourth press: the system turns off.

If the speeds ever feel out of order, count presses from off. The first press is always high and the fourth press always turns the blower off. On the digital touchpad, touch the air bubble icon once to start, use the plus and minus buttons to raise or lower the intensity, and hold the icon for two seconds to shut the air massage off. The typical air pump on the spec sheets is a 4.5A 500W three-speed blower, and the Elite uses a 6.4A blower. The first video shows where Ella places the jets, including hip, foot and bidet positions, and introduces the three-speed system with Auto Purge.

Auto Purge, the Cycle That Surprises New Owners

Some water works its way into the air lines during a bath, and an air bath tub needs a way to clear it. About 20 minutes after you turn the air pump off, Auto Purge starts on its own and runs the blower for 120 seconds to blow the residual water out of the lines so no moisture lingers to feed mold or mildew. It is fully automatic, it cannot be stopped, and it is completely normal even if it starts while you are still in the tub or after you have left the room. If you hear the blower run briefly on its own after a bath, that is the purge doing its job. The hydro side has its own helper, an ozone generator that runs whenever the hydro jets are on, so a tub with both systems cleans its lines in two different ways.

Filling and Staying Warm in an Air Bath

Every air jet must be under water before you start the blower, which on most tubs means a full fill. Air massage also has no heater. The in-line heater on an Ella tub sits in the hydro loop and maintains, but does not raise, the bath temperature only while the hydro pump is running, as What Is an In-Line Water Heater on a Walk-In Tub? explains. An air-only bath therefore cools the way an ordinary bath does, so start with comfortably hot water from a large enough home water heater and keep the bath at or below 100.4 degrees Fahrenheit. On a tub with both systems, it is the hydro heater, not the air blower, that keeps the water warm.

Bath Products and Cleaning in an Air Bath Tub

Because the blower churns the water constantly, a normal capful of bubble bath produces far more foam than in a standard bathtub. Use a fraction of the usual amount, let the jets run for a minute before adding more, and switch the air off for a moment if the foam gets ahead of you. Can You Use Bubble Bath or Shampoo With the Jets Running? has the full foam routine. Epsom salts are fine once fully dissolved, with the best practice of running the air massage first and adding the salts for a still soak afterward, while bath bombs, oils and bath beads are the products to leave out, as Can I Use Epsom Salts, Bath Bombs or Bubble Bath in My Walk-In Tub? explains.

Once a month, and before the first bath in a new tub, run the vinegar flush: mix 2 cups of white vinegar with 2 cups of water, fill the tub to 1 inch above the highest jets, add the mixture, run the tub for 10 minutes, then drain. If the tub has sat idle, check the GFCI, the green LED on the blue control box and the air hoses behind the push buttons before pressing anything, following How Do I Start Using a Walk-In Tub That Sat Unused for Years?. A loose push-button hose is the usual reason a bubble jet switch goes quiet. For a ticket at ellasbubbles.com/support, note your therapy package, how the Air button responds to each press, whether the Auto Purge fires after a bath, and your model and serial number.

Watch: Walk-In Tub with Push Controls & Digital Touchpad for Easy, Effortless Bathing | Ella’s Bubbles with chapters and a full transcript.

Related Guides

• What Are Hydro Massage Jets on a Walk-In Tub?
• Hydro Massage vs Air Massage vs Microbubble: What Each System Does and How They Combine
• My walk-in tub turned on by itself: the air massage Auto-Purge is normal

Common Questions