If your walk-in tub turned on by itself a little while after your bath, or even while you are still relaxing in the water, that is the Auto-Purge feature, and it is completely normal. On tubs with the three speed air massage, about 20 minutes after you turn the air massage pump off the air system starts automatically and runs for 120 seconds (2 minutes), blowing air through its lines to clear out the water that naturally flows back into the piping so mold and mildew cannot form. It cannot be interrupted, it stops on its own, and there is no need to get out of the tub while it runs.

Watch: Auto-Purge Explained

Here is the guidance from the video, written out:

1. The air massage buttons work with gentle pushes: one push for high speed, a second push for medium, a third for low, and a fourth push shuts the system off. Do not press too hard or too deep, since pushing too hard may damage the internal mechanism. A gentle push with the palm of the hand works well for anyone with arthritis or limited mobility. Our hydro and air massage controls article covers every button.
2. After the air pump is turned off, some water naturally flows back into the piping system. Left there, it would create mildew or bacteria.
3. About 20 minutes after the pump shuts off, Auto-Purge turns on automatically and runs for 2 minutes, blowing air through the system and drying out the lines.
4. This happens even if you are still bathing in the tub. There is no cause for concern. Just let Auto-Purge run its course and it will shut off after 2 minutes.
5. You can exit the tub normally after draining, even while Auto-Purge is running. The tub will sound like it is still running, but it is only the Auto-Purge doing its job.

The Three Speed Air Massage and Auto-Purge Together

This second video shows the air massage jets in the hip, foot, and bidet positions, activated by push buttons or the digital controller, and explains that the purge activates about 20 minutes after the tub is turned off to clear leftover moisture and prevent mold and mildew. If you have a printed manual that words the trigger differently, the operative facts are the same: automatic, about 20 minutes after shutoff, 120 seconds, self-stopping, and normal.

Auto-Purge at a Glance

Auto-Purge and Ozone: Two Different Helpers

Auto-Purge belongs to the air system. Tubs with hydro massage also have an ozone generator that switches on with the hydro pump to sanitize the water and lines, and when it runs it makes a light humming noise, which is also normal. Our ozone sanitation article explains that side. Neither system replaces the monthly vinegar flush described in cleaning and monthly maintenance.

When to Reach Out to Us

A 2 minute purge cycle after each use of the air massage is healthy, normal behavior. If your purge cycle keeps running continuously and will not shut off after 2 minutes, turn the tub off at the breaker and contact technical support so we can check the control system with you; a stuck relay or control box is the usual cause, and our control box reset guide is a good first step. And if you ever see mold appear despite Auto-Purge, run the standard flush, 2 cups of white vinegar with 2 cups of water, filled 1 inch above the highest jets, pumps on for 10 minutes, then drain, and see black flakes or slime from the jets if it keeps returning.

Common Questions

Still need help? Open a ticket at ellasbubbles.com/support or call (800) 480-6850 and our team will be happy to walk you through it.