I have my Pentair R171218 Rainbow 320C in the bottom-feed configuration. I normally use bleach but have it as a backup for when I'm travelling. I try to dial it in when opening the pool, but seem to struggle getting the chlorine level up. My CYA is around 30 and I'm trying to hold at 2 ppm FC. So far this week I'm having to add .5 FC per day. The water is crystal clear with a complete water change last week for a new liner. I struggled with the same thing last year and blamed the cold water temp (currently around 68 deg F). There really doesn't seem to be any way to inspect or test this unit, it either works or it doesn't and you are either one of the lucky ones or your aren't (I'm apparently not). I feel like I had this working 2 or 3 years ago and am just at a loss to determine what has changed.
One option is to attempt the top feed configuration. I lost the parts to do this and am concerned about how accurately it can control in that configuration. Wouldn't you get a lot more trichlor dissolving when the hopper is full as opposed to when it is low? It doesn't seem like a good approach.
One option is to attempt the top feed configuration. I lost the parts to do this and am concerned about how accurately it can control in that configuration. Wouldn't you get a lot more trichlor dissolving when the hopper is full as opposed to when it is low? It doesn't seem like a good approach.
