Chemistry Controllers For Commercial Pools

ORP Chemistry Controllers

In Blog by TMI Sustainable Aquatics

We are taking a closer look at ORP Chemistry Controllers.

ORP controllers are far and away the most prevalent controller, both because of the lower price point and because of the relatively simple operation.  This is their upside, they can be installed in just about any type of pool, in any type of facility and given the correct programming options, can work fairly well to make sure there is chlorine in the water. The main limitation is that ORP is effectively a Qualitative measurement where PPM is a Quantitative measurement. This means we are only able to correlate one to the other, which leaves room for error and drift. ORP it is much less precise than a PPM based system, and as such will tend to hold to a wider “band” vs. a real set “point”. When you are only concerned about “having chlorine” and not trying to hold to within 0.5 – 1 ppm, ORP should work just fine for you.

  • Pros:
    • Inexpensive
    • Simple
    • Flexible
  • Cons:
    • Lack Accuracy
    • Not fully understood by operators
    • May have limited control options
  • What to expect:
    • Expect to check the system at least 2-3 times per day, making minor adjustments as needed.
    • Expect chlorine to be about +/- 1.0 ppm of your target level.
    • Expect regular maintenance cycles of 30-60 days.

Do you use ORP Chemistry Controllers at your facility? If not what do you use? Tell us in the comments below.