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What the Air + Hydro + Hydro Foot Digital Controller Schematic Shows (Companion, Escape, Tub4Two, Big4Two, Shak, Big4One, Transfer60, TransferXXL)

Updated September 2026

This page explains the Air + Hydro Therapeutic Massage + Hydro Foot Component Diagram With Digital Controller, published by Ella's Bubbles as air-hydro-hydro-digital.pdf in the walk-in-tub schematics folder (revision 10-16-23). It is the schematic for tubs that combine an air massage pump with two independent hydro pumps and use a digital controller, rather than plain push buttons, for the air and seat hydro systems. If your tub has a digital touchpad on the deck and the Air + Hydro + Hydro Independent Foot Massage package, this is your drawing. Below you will find which tubs the diagram lists, the seven numbered components, how the digital controller and the foot button divide the work, where the two hydro pumps and the in-line heater sit, the electrical requirements printed at the top, and a note about a second file name that serves the very same diagram.

Which Tubs This Diagram Lists

The "Available On" box prints Companion, Escape, Tub4two, Big4two, Shak, Big4one, Transfer60, and XXL. "XXL" is the schematic's short form for the TransferXXL. Notice how many two-seat tubs appear here: the Companion, Escape, Tub4Two, and Big4Two are all two-seater models, joined by the Big4One, the Shak, the Transfer60, and the TransferXXL. If you own one of these with the three-system package and a digital touchpad, this is the diagram to keep with your paperwork. Owners of the Royal, Monaco, Elite, and Capri with push-button controls should use the push-control version of this schematic instead.

The Seven Numbered Components

The legend along the bottom of the sheet lists seven components. They are reproduced below exactly as printed.

NumberComponentPrinted details
1Air Massage SystemRefer to Technical drawing for jet Count; Variable Speed Pump with Auto Purge; ON/OFF Digital Controller
2Hydro Massage SystemHydro Pump; Hydro Massage Air Flow Intensity Control; ON/OFF Digital Controller
3Hydro Foot Massage SystemHydro Pump; Hydro Massage Air Flow Intensity Control; ON/OFF Button
4In-Line Water HeaterControl Box
5Electronic Component ControllerControl Box
6Ozone GeneratorOzone Sanitation System
7Led LightChromatherapy

The legend refers you to your tub's technical drawing for the air jet count, since the count differs by model while this schematic is shared across eight of them. The air pump is a variable speed pump with Auto Purge: about 20 minutes after you turn the air massage off, it starts on its own and runs for 120 seconds to blow leftover water out of the air lines. That is normal and stops by itself.

Digital Controller for Air and Seat Hydro, Button for Foot Hydro

The key difference from the push-control diagram is in the ON/OFF entries of the legend. Items 1 and 2, the Air Massage System and the (seat) Hydro Massage System, are printed with "ON/OFF Digital Controller". Item 3, the Hydro Foot Massage System, is printed with "ON/OFF Button". So on a tub built to this diagram:

  1. The digital controller on the deck turns the air massage and the seat hydro massage on and off. The drawing also shows a Hydro Massage Push Control wired alongside the digital controller for the seat hydro system.
  2. The foot hydro massage is switched by its own separate button.
  3. Both hydro systems keep their own Air Flow Hydro Massage Intensity Dial Control, one for the seat jets and one for the foot jets, so intensity is still set at the dials rather than on the touchpad.

The Digital Controller and the LED Light are wired to the Control Box, which carries the Load 1 and Load 2 outputs. As on the push-control diagram, Load 1 serves the Air Pump and its "Air Out to Jets" line, and Load 2 serves the Ozone Generator and its "Ozone Out to Hydro System" line. For a side-by-side look at the two control styles, see push controls versus the digital touchpad.

Two Hydro Pumps and Where the Heater Sits

The drawing shows two hydro pumps, printed as the Seat Jets Hydro Pump and the Foot Jets Hydro Pump. Each is fed by its own dial and switched separately, which is what makes the foot massage independent: you can fill only to the foot well and run the foot jets alone, or run the seat jets, foot jets, and air massage together. The In-Line Water Heater is drawn in the foot hydro loop, on the line that runs from the foot pump's "Out" to "To Hydro Jets" and on to the foot Hydro Jets. It maintains the temperature of water already in the tub while that pump circulates; it is not a heater for incoming water. Read independent foot massage explained for more on the two-pump design. On two-seat models, this separation also explains why one set of jets can run while another does not; two-seat tub, one side not working walks through that situation.

Electrical Printed on the Diagram

ItemPrinted requirement
#1 Wall OutletGFCI Protected, Dedicated Line, 20 AMP, 120 Volts
#2 Wall OutletGFCI Protected, Dedicated Line, 20 AMP, 120 Volts
Air Pump110-120 V, 4.5 A

Component branches are marked "Electrical 110V", and the footer carries the disclaimer "Please View Specifications for Electrical Amperage (A), Voltage (V) and Wattage (W)." Give your electrician this schematic for circuit count and GFCI protection, and your model's spec sheet for each pump's amperage; electrical requirements by model collects that information in one place.

A Second File Name for the Same Diagram

Ella's schematics folder also serves a file named air-hydro-hydro-digital-heat.pdf. Despite the "heat" in the name, that file prints the same 10-16-23 Air + Hydro Therapeutic Massage + Hydro Foot Component Diagram With Digital Controller described on this page, with the same eight-model list, the same seven components, and the same two-outlet electrical block. It does not add surface heater pads or a heat keypad. If you were sent either file name, you are looking at the same drawing. Should your tub also have the Heated Seat and Backrest option, ask your Ella dealer or the team at ellasbubbles.com/support or (800) 480-6850 for the diagram that matches your full configuration.

Download the official document: Air + Hydro Therapeutic Massage + Hydro Foot Component Diagram With Digital Controller

Common Questions

Which tubs does the digital controller schematic list?
The diagram prints Companion, Escape, Tub4two, Big4two, Shak, Big4one, Transfer60, and XXL, where XXL means the TransferXXL. It applies to those tubs when ordered with the Air + Hydro + Hydro Foot package and a digital controller.
Which systems does the digital controller switch?
The legend prints "ON/OFF Digital Controller" for the Air Massage System and the seat Hydro Massage System. The Hydro Foot Massage System is printed with its own "ON/OFF Button". Intensity for both hydro systems is still set at their separate dials.
How many pumps are on this diagram?
This diagram shows three pumps: one variable speed air pump with Auto Purge, one Seat Jets Hydro Pump, and one Foot Jets Hydro Pump. The two hydro pumps, the Seat Jets Hydro Pump and the Foot Jets Hydro Pump, are independent, meaning you can run the foot jets alone or run the seat jets, foot jets, and air massage together. This independent design also explains why one set of jets can run while another does not on two-seat models.
Where is the in-line water heater on this diagram?
The in-line water heater is drawn in the foot hydro loop on this diagram. Specifically, it is located on the line that runs from the foot pump's "Out" to "To Hydro Jets" and on to the foot Hydro Jets. This heater maintains the temperature of water already in the tub while the foot pump circulates it; it is not designed to heat incoming water.
Is air-hydro-hydro-digital-heat.pdf a different schematic?
No, the file named air-hydro-hydro-digital-heat.pdf is not a different schematic. Despite the "heat" in its name, that file prints the very same 10-16-23 Air + Hydro Therapeutic Massage + Hydro Foot Component Diagram With Digital Controller. It features the same eight-model list, the same seven components, and the same two-outlet electrical block, and it does not add surface heater pads or a heat keypad.
What electrical service does the diagram print?
Two wall outlets, #1 and #2, each GFCI Protected, Dedicated Line, 20 AMP, 120 Volts, plus an Air Pump rating of 110-120 V, 4.5 A. The footer refers your electrician to your model's specifications for the other components.
Why does the air pump start on its own after my bath?
The air pump starts on its own after your bath due to the Auto Purge feature, which is printed in the legend of the schematic. Approximately 20 minutes after you turn the air massage off, the variable speed air pump will automatically start and run for 120 seconds. This process is designed to blow leftover water out of the air lines and is completely normal, stopping by itself.

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.

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