Support Center / Therapies & Operation / What Is Auto Purge on a Walk-In Tub?
Back to Therapies & Operation

What Is Auto Purge on a Walk-In Tub?

Updated September 2026

▶Glossary5
  1. How It Works
  2. Which Ella Models Have It
  3. What to Know as an Owner
  4. Related Guides
  5. Common Questions

Auto Purge is the self-cleaning cycle on Ella air massage systems. About 20 minutes after you turn the air massage off, the air pump starts on its own and runs for 120 seconds to blow leftover water out of the air lines. Owners sometimes call it the auto-purge cycle, the self-purge, the air dry cycle or "the tub turning on by itself," and it is completely normal.

How It Works

After an air bath, a little water flows back into the air piping and the jets on the floor and seat. If it sat there, it could grow mold and mildew. So the system waits about 20 minutes after the air pump is switched off, then runs the blower for 120 seconds to push that water out through the jets. The cycle cannot be interrupted and stops on its own. If it starts while you are still in the tub, there is no need to get out; if you would like to leave while it runs, just drain and exit normally. Some printed manuals say the purge fires after the pump is turned on, which is a known wording error; the correct trigger is the pump being turned off. The plain-language version is in Why Did My Tub Turn On by Itself and The Air Massage Auto-Purge Is Normal, and the button sequence for the air speeds is in Hydro Massage vs Air Massage Controls.

Interior of an Ella walk-in tub with residual water draining past the floor air jets after a bath
Auto Purge blows the water left in the air lines back out through the air jets after your bath.

Which Ella Models Have It

Any Ella tub ordered with the three-speed air massage has Auto Purge, whether the air system came alone, as Hydro plus Air, or in a triple package. That covers air packages on the stainless-door, Ultra, outward-swing, two-seat, Transfer and LayDown families. Hydro-only and soaking tubs have no air blower and therefore no purge cycle, which includes the Standard, Standard60, Zen, Zen60 and Flow. The package-by-package list is in What Comes With Each Therapy Package.

What to Know as an Owner

Expect a burst of air through the jets roughly 20 minutes after every air bath and let it finish. Auto Purge clears the air lines, ozone sanitizes the hydro lines, and neither replaces the monthly vinegar flush: 2 cups white vinegar and 2 cups water, tub filled to 1 inch above the highest jets, jets run for 10 minutes, then drained. Because the cycle can run after the tub has drained, it is one of the sounds covered in The Sounds an Ella Walk-In Tub Makes. If the blower runs continuously instead of stopping after 120 seconds, switch the tub off at the breaker and open a ticket at ellasbubbles.com/support; a stuck relay or the control box is the usual cause. If the purge never seems to happen after an air bath, the team can check the air pump control with you. For a ticket, have your model, serial number, which therapy package you have, how long after the bath the air started and how long it ran.

Common Questions

Why did my walk-in tub turn on by itself?
That was the Auto Purge cycle, which is a completely normal self-cleaning function on Ella air massage systems. Approximately 20 minutes after you turn the air massage off, the air pump starts on its own and runs for 120 seconds to blow leftover water out of the air lines. This cycle prevents mold and mildew from growing in the air piping and jets on the floor and seat.
Can I stop the Auto Purge once it starts?
No, you cannot interrupt the Auto Purge cycle once it starts, and there is no need to. It runs for 120 seconds and stops on its own. If the cycle starts while you are still in the tub, you do not need to get out; you can drain and exit normally if you wish to leave.
Does Auto Purge run after a hydro massage bath?
No, Auto Purge does not run after a hydro massage bath because it belongs to the air massage system only. Hydro-only and soaking tubs, including the Standard, Standard60, Zen, Zen60, and Flow models, have no air blower and therefore no purge cycle. The hydro lines are sanitized by the ozone generator while the hydro pump runs during a hydro massage bath.
Does Auto Purge mean I can skip cleaning the tub?
No, Auto Purge does not mean you can skip cleaning the tub. While it keeps the air lines clear of standing water, the monthly vinegar flush and regular surface cleaning still apply. The monthly vinegar flush involves filling the tub to 1 inch above the highest jets with 2 cups white vinegar and 2 cups water, running the jets for 10 minutes, then draining.

About this guide. Answers in the Ella’s Bubbles Support Center are compiled from real conversations with tub owners, our technicians’ notes and the product documentation, then reviewed by our team. Tub models and options have evolved over the years, so a detail here may differ slightly from your exact tub. If something looks different on yours, send us your serial number and a specialist will confirm it for your model.

Related guides

Did this solve your question?

If not, open a ticket and our team will pick it up from here.

Open a Support Ticket