chlorinator instalation

[TrevNJPool]

Hello, I'm new to the forum but have found some useful information on this forum so I decided to join.
The question I have is, I'm installing an offline chlorinator. The pool guy said to install it on the return line for the in and out so the chlorine gas doesnt back up and wrinkle the liner. Also it is receiving clean water through the chlorinator. The Hayward CL220 instructuons say to do it before the filter. Just wondering if it matters where the inlet water comes from. Thank you

 

[JasonLion]

Welcome to TFP!

Both approaches can work. I prefer the approach suggested in the manual, which works better in some cases. Often enough it makes no difference, but with a variable speed pump the return line for both in and out approach will often not work.

By the by, "chlorine gas doesnt back up and wrinkle the liner" isn't something that can actually happen regardless of how it is installed.