Rainbow Chlorinator repair?

I have a rainbow 320 chlorinator that, over time, seems to be putting out less and less chlorine.

When the pool was new, it'd digest about 3 or 4 tablets a week at a setting of 2.5 to 3. Now it takes about 3 weeks to digest that much, at a setting of 5, and I wind up having to constantly add Hypo to bring chlorine up.

The pool was built in '99.

Any ideas what the issue could be?

Sounds like it's clogging up with deposits. Might be time to replace it if it cannot be cleaned-out. I believer the Rainbow 320 was the only chlorinator Ben would recommend. Personally, I prefer floaters. Cheaper and they are easy to replace.

Carl

Do I have to replace the "Tee" in the main return line, or can I just swap out the unit by removing it from the Tee?