How Do I Install a Replacement Ozone Generator on My Walk-In Tub?

Installing a replacement ozone generator on an Ella walk-in tub is the disconnect procedure run in reverse: switch off the tub's GFCI breaker, remove the access panel, separate the old unit from the T connection that joins the hydro pump and the ozone generator, plug the new unit's cord into that same T, and restore the T between the control box and the hydro pump. The disconnect steps, and the video that shows the exact cord and T connection you will be handling, are in Disconnecting or Servicing the Ozone Generator on Your Walk-in Tub. Ella does not send technicians, so the swap is done by you or a local licensed electrician, with the replacement part shipped under the warranty.

Confirm the Generator Is the Part That Failed

The ozone generator is a small sealed box with its own cord, mounted under the deck near the hydro pump. It is wired in line with the hydro pump, so it starts and stops automatically with the hydro massage and runs for as long as the jets are on. When it is working you notice three things: a light hum of its own, a faint hiss as air is drawn through the small check valve on top, and a faint clean, slightly metallic smell in the water that clears quickly with the bathroom fan. All three start and stop with the hydro pump. The unit draws only 0.04A, a figure that is easy to confuse with the 0.5A LED chromatherapy light, and the two ratings should not be swapped.

Before ordering a part, rule out the two things that mimic a dead generator. If your tub has a separate O3 button that does nothing, the fault is more often the air-actuated relay or its clear air tube on the control box than the generator itself. Press the LED light button and note the click from under the tub, then press the O3 button and listen for the same click. No click means the tube is not seated firmly at the relay, and swapping the LED and O3 tubes at the control box shows whether the ozone relay works. Ozone (O3) Button Does Nothing walks through that test, and a failed relay ships under the parts warranty. Second, run the hydro pump with the tub filled at least 1 inch above the highest jets and confirm whether the hum and smell simply stopped being noticeable rather than stopped altogether; Why Is There a Metallic Smell When the Jets Run? describes what normal operation is like. A loud rattle instead of a light hum, or no hum and no scent at all with the hydro jets running, is what points at the generator.

What the T Connection Is

The generator gets its power through a T. One end of the T goes to the plug coming from the central control box, one goes to the hydro pump, and the third is the ozone generator's own cord. That is what ties the two together electrically, and it is why the hydro pump keeps working normally without the generator. When a defective generator is isolated while the replacement is on its way, both ends of the T are disconnected, the ozone cord is wrapped with a cable tie and secured within the frame of the tub, and the hydro pump plug is reconnected directly to the plug from the control box. The video on this page shows each of those moves on a real tub. If your tub is already in that state, expect to find the hydro pump plugged straight into the control box and the old cord tied to the frame.

Fitting the Replacement, Step by Step

1. Turn off power to the tub at the GFCI breaker. The tub runs on its own dedicated circuits, so nothing else in the house is affected.
2. Remove the magnetic access panel next to the door so you can reach the equipment area safely.
3. Locate the ozone generator near the hydro pump and follow its cord to the T connection. If the unit was isolated earlier, cut the cable tie holding the old cord to the frame.
4. Unplug the old generator's cord from the T. If the hydro pump is plugged directly into the control box plug, unplug it there as well.
5. Set the new unit where the old one sat, clear of moving water and equipment, with the check valve on top left unobstructed so it can draw air.
6. Restore the T: the control box plug on one end, the hydro pump on the other, and the new generator's cord on the third.
7. Refit the access panel and switch the breaker back on.

The published guides describe the cord and the T connection. If your replacement arrives with anything beyond the sealed unit and its cord, or if a hose on the old unit leads somewhere you cannot see, send a photo through your ticket before disturbing it rather than guessing. The team answers by ticket and phone, and that is the point at which a licensed electrician is worth having on site if you are not comfortable under the deck.

Testing the New Unit

Fill the tub to at least 1 inch above the highest jets before the hydro pump runs. A pump run dry is damaged permanently, so never test on an empty tub. Start the hydro massage and listen for the light hum and the faint hiss from the check valve, then notice the slight clean scent in the water. Turn the hydro off and confirm the sound and smell stop with it. On a tub with an O3 button, press it and listen for the relay click under the deck. A hum that continues while the tub sits idle, or a smell strong enough to be unpleasant, is a reason to unplug the unit and open a ticket. The everyday sounds of a healthy tub, including the ozone hum and the relay clicks, are listed in Why Does My Walk-In Tub Make a Buzzing or Hissing Noise?. Once the generator is running again, keep up the monthly flush of 2 cups white vinegar and 2 cups water, tub filled to 1 inch above the highest jets, jets run for 10 minutes, then drained; ozone sanitizes the hydro lines during use but does not replace that routine.

If You Would Rather Leave It Disconnected

Ozone sterilization is a hygiene feature rather than a therapy, and it needs nothing from you, but running the tub without it is a personal choice some owners make. The hydro massage system continues to work normally with the generator unplugged, and the same T connection lets you reconnect it later by reversing the steps. On a new order the generator can be excluded by special request before the tub is built. For a ticket at ellasbubbles.com/support, or a call to your Ella dealer or the team at (800) 480-6850, have your model, serial number and therapy package ready, along with a photo of the unit and its T connection through the access panel and a short phone video with sound if the noise is the concern.

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

Related Guides

• What is ozone sanitation, and is the light humming noise from my tub normal?
• Why Does My Walk-In Tub Ozone Generator Run All the Time, and Can I Turn It Off?
• Ordering a Replacement Air, Hydro or Microbubble Pump: What to Send So the Right One Ships

Common Questions