How-To Guides | Ozonator Installation - Spa Ozone

Install an ozonator for cleaner water with less chemical use. Most of today's hot tubs are ozone-ready, so adding or replacing one is a snap! Some spas take a bit more effort... we'll show you how. You'll save a bundle when your buy your ozonator from The Spa Depot, where quality comes at a fair price.

Ozonators convert oxygen into ozone, which then oxidizes contaminants. A clear air line from the ozone generator is connected to your spa's plumbing system. The flow created by the pump creates suction, which draws the ozone into the spa water where it dissolves. The ozonator itself is connected to your spa control system, which supplies power and regulates its cycles of operation.

Clarathon HCD-55 ozonator kit with tubing, clamps and check valve

Step-by-step instructions are provided with every spa ozonator kit we sell, to make installation easy. CD ozonators such as our Clarathon HCD-55 Hi-Output Spa Ozonator Kit have special technology which greatly increases lifespan and output compared to older UV designs.

See: Safety Recommendations

Preparing for Ozonator Installation

  • Verify that your spa will accept an ozonator and determine the voltage required.
  • Check for and correct all leaks in plumbing.
  • Check filters: clean with ecoTUB Filter Soak, Power Soak, or replace spa filter cartridge.
  • For best results, drain water and fill with fresh water. It is easier for the ozonator to maintain purity in a fresh start of clean water. Use Spa System Flush prior to draining.
  • Balance water chemistry, shock, and use a sanitizer system. Ozone reduces the amount of chemicals needed and improves water quality, but will not replace your sanitizer.
  • Verify the plug type you will need and voltage.

Ozonator Components you'll need to Purchase

  • If you're replacing an existing ozonator, or installing in an ozone-ready spa, then you'll normally only need an ozonator kit. Most modern hot tubs are ozone-ready.
  • Some spas will also require the installation of a Venturi Injector.
  • If installing a Venturi Injector, we also highly recommend the addition of our Ozone Turbo Mixer, which dissolves up to 33% more ozone.
  • If you are installing a new ozone system from scratch, you may also need an Ozone Wall Fitting Jet.

We'll explain the different installation schemes below.

Spa Equipment Access

After disconnecting the electrical power, remove the spa's access panel.


Installation in an Ozone-Ready Spa

Ozone-ready spas usually have a small ozone jet near the bottom of the spa. This jet will have a water port, and an air (ozone) port. When no ozonator is present, the jet acts as a water jet only. A clear ¼" I.D. capped-off air tube from this jet should be hanging in the equipment bay, if no ozonator has been installed.

Ozone Line Connection

Locate the ozone suction connection. This is typically ¼" I.D. x ⅜" O.D. vinyl air tubing. The tubing has a cap, which is snipped off to accommodate the one-way check valve included in the ozonator kit. This valve helps prevent water from accidentally entering the ozonator.

Attach the ozone check valve to one end of the vinyl tubing supplied with your ozonator kit. The other end of the check valve attaches to the spa's suction tubing.

The air (ozone) flow direction is away from the ozonator and toward the spa. The valve may be marked as to direction. If not marked, you can determine the flow direction by blowing into one end of the valve. This is important, as installing the check valve backward will prevent functionality.

Attach the other end of the air tubing to the ozonator's barbed fitting.

Installation in Non Ozone-Ready Spas

hot tub ozonator ozone kit installation diagram

Jet Water Line Connection Method

The simplest way to hook up the ozone line is to use an ozone venturi injector. Placed into a jet water line (typically ¾" I.D. tubing), the water flow provides suction, which draws ozone into the spa.

This method is very effective for dissolving ozone. Select a jet as near the bottom of the spa as possible, for maximum water contact. Make sure to observe the flow orientation, as noted on the injector. The ozone line should be double-looped above the water line (called a Hartford loop). Correct installation of the supplied air check valve is critical to prevent water intrusion into the ozonator.

Dissolving Ozone More Effectively

Achieve optimum ozone effectiveness by adding our Ozone Turbo Mixer, which increases the amount of ozone dissolved in the water by up to 33%. It also compensates for low gas/water contact time in short tubing runs from the Injector to the ozone wall jet.


Electrical Connection

Most spa control systems have an ozone receptacle to supply power to the ozonator, and control its cycle.

There are many plug types used for various hot tub makes, the 4-prong Amp style being the most common.

See: Safety Recommendations


IMPORTANT: Make sure the voltage is the same as prescribed on the label of the ozone generator. Over-voltage or under voltage will void customer warranty. If in doubt, refer to your spa's manual or check with a voltage tester (available at any home center).

If your spa pack doesn’t have an ozone connection outlet, the electrical cord should be wired to the pump controller. A qualified electrician should connect it such that the ozonator comes on only when the pump is on. (For 2-speed pumps, ozonators should be wired to the low-speed pump circuit).


Internal Connection

After removing the access cover to the control box, the ozonator's electrical connector simply plugs inside. Refer to your spa control's manual for location of ozone receptacle and plug type.

External Connection

Some spa controls use external style receptacles for ozonators and other equipment components. These receptacles are typically located on the side of the spa pack.

Mounting Instructions

Your ozonator may be mounted with screws almost anywhere in the equipment bay, space permitting, preferably to a wood support. Mount the unit as high as possible.


Safety Precautions & Recommendations:

  • Turn off hot tub power at source breaker before installing or servicing ozonators. Disconnect the spa's power cable (120V), or flip the GFCI disconnect breaker (240V) as an additional secondary precaution.
  • All applicable electrical codes must be followed during and after installation. All connections to be made by a qualified electrician. Electrical installations carry the risk of electric shock.
  • Connect only to a properly grounded, GFCI-protected power source. Do not bury cord.
  • Install the ozone generator with a looped air supply hose (Hartford loop) above the water level. Make sure the check valve is properly installed, and oriented in the correct direction.
  • Make sure ozonator voltage matches the system's ozonator circuit output voltage. Most systems use 120V, but many operate at 240V.