Ozonator troubleshooting: pressure problems. (Maintenance & Cleaning).
If you've had trouble installing ozone on the return line of a spa or swimming pool, you're not alone. I often get calls from people who have lost vacuum from the venturi injector. Here are several examples of what causes pressure loss and how to remedy it:
Adjusting the injector valve
A venturi develops suction through a pressure drop. The greater the pressure drop, the greater the suction. One of the most common mistakes is not adjusting the injector valve properly. Closing the valve results in a greater pressure drop, thus a greater amount of suction. Opening it will give you the opposite result: lower pressure drop and lower suction.
Size the venturi
When installing an injector in a spa application, you must make sure the venturi is sized properly for the flow (gpm) of water and pressure of your pump.
An oversized venturi will result in low vacuum and undersizing will result in insufficient water flow and inadequate vacuum.
A common cause of ozone generator failure is water backing up into it. You can solve this by installing a water-release valve.
Reduce back-pressure problems with pools by changing eyeball fittings on the return line. You can also reduce return-line back pressure by using 45-degree PVC fittings instead of 90-degree fittings after the injector.
Clean the filters
Adding an injector to the filtration system increases the pressure requirements. As the filter grows increasingly dirty, the water flow and vacuum developed by injectors reduces. A clean filter becomes paramount.
In-floor cleaning systems
Installing an injector ozone system into the same return line, as an in-floor cleaning system could cause poor vacuum. If you use a standard pool injector with an in-floor cleaning system, you may not get the proper vacuum because the cleaning system requires a certain amount of back pressure. A properly operating cleaning system may shoot water from the suction port because of high back pressure. Achieving proper vacuum in the injector results in lost back pressure for the cleaning system.
Solution: Increase the size of the venturi. This provides more water flow for sufficient vacuum while producing enough back pressure for the in-floor cleaning system.
Wayne Babcock is OEM manager and technical training manager at DEL Industries, based in San Luis Obispo, Calif.