How Do I Tell If My Walk-In Tub Ozone Generator Stopped Working?

An ozone generator that is working gives three signs: a light hum from under the deck, a faint hiss of air being drawn through the small check valve on top of the unit, and a slight clean scent when the hydro jets run. If those signs have disappeared, or the hum has turned into a rattle, the unit may have stopped, and the way to know for sure is to check it against when it is supposed to run on your therapy package. The hydro jets keep working with or without ozone, so working jets are not proof that the generator is. The feature itself is described in What Is Ozone Sterilization on a Walk-In Tub?.

First, Know When It Is Supposed to Run

The most common report of a dead ozone generator is not a failure at all. It is an owner listening for the hum at a time the generator is not meant to be on, or the reverse, an owner worried because it never seems to stop. When the generator runs depends on the therapy package, so match your tub to the table before you decide something is wrong.

The consequence is simple. On a hydro-only tub, silence while the tub is idle and powered is worth investigating, and a constant hum is not. On a dual massage tub the opposite is true: silence while the pump is off is exactly right, and the hum should appear only when the jets start. The package-by-package behavior, and why owners of hydro-only tubs sometimes think the unit never stops, is in Why Does My Walk-In Tub Ozone Generator Run All the Time, and Can I Turn It Off?. Ozone can also be excluded by special request on a new order, so if your tub was ordered that way there is no generator to check.

The Checks, in Order

1. Fill the tub with water to at least 1 inch above the highest jets. Never run any pump on a tub filled below the jets, because a pump run dry is damaged permanently.
2. Press the hydro massage control and listen. The water pump makes a moderate, steady hum. Under it, the ozone generator makes a lighter hum, and a faint hiss comes from the check valve on top of the unit as it draws air. Tubs with independent foot massage run a second water pump, so expect two pump hums when both systems are on.
3. Notice the scent. A slight clean, slightly metallic smell while the jets run is the ozone in the water, and it clears quickly with the bathroom fan. That smell is one of the clearest working signs, which is why it is described in Why Is There a Metallic Smell When the Jets Run?.
4. Turn the hydro pump off. On a dual massage tub the light hum and the hiss should stop with the pump. On a hydro-only tub the light hum continues.
5. If you heard none of the signs, switch the tub off at the breaker, open the access panel, and look for the ozone generator under the deck, wired in line with the hydro pump. Find the T connection that joins the hydro pump and the ozone cord. A cord that is cable-tied to the frame with the pump plugged straight into the control box means the generator was disconnected at some point, and that is the reason it is silent.

The generator draws only 0.04A, so a working unit does not show up on your electric bill and does not change how the jets feel. Its entire output is the hum, the hiss and the scent. Do not confuse that rating with the LED chromatherapy light, which is a separate 0.5A line. The whole catalog of normal tub sounds, so you can separate the ozone hum from the relay click, the breather hose and the pump, is in Hums, Clicks, Whooshes and Buzzes: The Sounds an Ella Walk-In Tub Makes and Which Ones Are Normal.

Sounds and Smells That Mean Stop

Some changes point away from stopped and toward switch it off. A loud rattle rather than a light hum, a bang, or a burning smell are not normal, and the tub should be switched off at the breaker and left off until it has been checked. A smell that is strong rather than faint, or that continues after the hydro pump stops, is also a reason to unplug that component and open a ticket. The questions that sort a normal working sound from one of these are in Why Does My Walk-In Tub Make a Buzzing or Hissing Noise?.

If It Has Failed

Nothing about the bath changes. Ozone sterilization is a hygiene feature rather than a therapy, and the hydro massage system continues to work normally without it. Until a replacement arrives you can isolate a defective generator using the same steps as a deliberate disconnect: locate the power cord from the ozone generator, find the T connection that joins the hydro pump to the generator, disconnect both ends of the T, wrap the disconnected ozone cord with a cable tie and secure it within the frame of the tub, then reconnect the hydro pump plug to the plug coming from the central control box. The video on this page shows exactly that procedure. Test the hydro pump afterward to confirm it starts and stops normally, and reverse the steps to reconnect later.

Ella does not send technicians. Under the warranty terms, replacement parts ship once the team has verified the problem, and a local licensed electrician handles the swap. Open a ticket at ellasbubbles.com/support or call (800) 480-6850 with your model, serial number and therapy package, a note on whether the hum is new or has changed, a short phone video with sound if it is safe to record, and a photo of the unit and its T connection through the access panel. While you wait, keep up the monthly flush of 2 cups of white vinegar with 2 cups of water in a tub filled to 1 inch above the highest jets, run for 10 minutes and drained. Ozone never replaced that flush, so a paused generator does not change your cleaning routine.

Watch: Ell'as Bubbles: Disconnecting The Ozone Generator with chapters and a full transcript.

Common Questions