How do you know if the ozonator is working?

Many spas are equipped with an ozonator to assist with disinfection. 

But how do you know if the ozonator is working?

If you see bubbles in the tub, usually coming from a grate in the middle of the tub, it might look like the ozone system is working. However, this is just air and says nothing about the presence of ozone in the water. 

Ozone can be produced in the ozonator in several ways. The ozone and air are drawn out of the ozonator via a venturi valve into the circulation pump piping. If the venturi is working, you will always see air bubbles, but this is no guarantee that the air contains ozone. If the ozonator is defective, no ozone will be produced.

You can measure ozone with special test strips; this is the only way to be sure. 

Depending on the brand and type of ozonator, it will last between 1 and 5 years.