Mazzei

Mazzei ozone mixing and injection parts for spas

Ozone only works on the water it actually dissolves into. A generator can be running perfectly and still make very little difference to a spa if the gas is simply bubbling through the pipework and venting out at the surface. The components listed here deal with that second half of the job: drawing the gas in, mixing it with the flow under pressure, and giving it enough contact time to react before the water returns to the shell. Here you will find the Mazzei Flash Reactor mixing chamber used alongside spa ozonators, together with the background needed to work out whether it is the right part for your installation.

What a mixing chamber does in an ozone circuit

A typical spa ozone set-up has three stages. The generator produces ozone, a venturi-style injector uses the pressure drop across a restriction to pull that gas into the water stream, and a mixing or contact vessel downstream keeps the gas and water together long enough for the ozone to dissolve and oxidise what it finds. Without that third stage, much of the gas stays as visible bubbles, rises in the footwell and is lost.

The Flash Reactor is the contact stage. It is plumbed in after the injection point and creates turbulence, so the fine bubbles are broken up and driven into solution rather than coalescing. Anything that does not dissolve should be carried away to a point where it can off-gas safely, usually well below the water line or via the filter compartment, never directly at a seat or headrest.

Where it sits in the plumbing

In most spas the ozone loop is taken off the circulation side rather than the jet pumps, so that it runs whenever the pump runs and is not dependent on a boost cycle. The usual order of components is:

• Bomba de circulación — provides the flow that drives the venturi.
• Injector — the venturi that creates the suction and introduces the gas.
• Válvula de retención — prevents water travelling back up the ozone tubing towards the generator, which is the single most common cause of a failed ozonator.
• Mixing chamber or flash reactor — the contact stage, such as the FR-75-HB.
• Return to the shell — ideally a low-level return or the filter area, so that any residual gas is diluted and vented away from bathers.

Ozone attacks many common materials, so tubing, seals and any fittings in the gas path should be of a type intended for ozone service. If the existing tubing has gone brittle, chalky or discoloured, replace it at the same time as the reactor; there is little point fitting a new contact vessel and feeding it through a cracked line.

Identifying the right part before ordering

Spa ozone kits vary a great deal between manufacturers, and parts are rarely interchangeable by eye alone. Before ordering, it is worth checking a few things:

• Código de modelo — note the full code stamped or printed on the existing body, such as FR-75-HB, rather than the description alone.
• Port size and connection type — measure the outside diameter of the pipe entering and leaving the old part, and note whether it is a barb, a glued socket or a threaded connection.
• Overall length and orientation — contact vessels need space in the equipment bay; measure between the fixed points of the pipework.
• Gas inlet — check the diameter of the ozone tubing currently used so the new part can accept it without an adaptor.
• Caudal — venturi injection depends on the pump actually producing enough flow and pressure differential; a tired circulation pump or a blocked filter will starve the ozone loop whatever is fitted downstream.

Where an exploded diagram is available for your spa, the position number for the ozone contact vessel is the quickest way to confirm a match, as several similar-looking bodies may have been used across one model range.

Mazzei at PoolParthub.com

Here we list Mazzei ozone mixing components for spa ozonator circuits, currently centred on the Flash Reactor FR-75-HB contact chamber. It is the part most often replaced when an ozone system is refurbished, since it sits in the wettest, most chemically aggressive part of the loop and is frequently disturbed when a generator or injector is changed.

The range is kept because ozone equipment is usually repaired piece by piece rather than replaced wholesale: a working generator paired with a degraded contact vessel still gives poor results, and a single component is a far smaller job than re-plumbing the bay. If you are unsure which part number your spa uses, note the markings on the existing body and the pipe sizes either side of it before choosing.