Issues with Rainbow Chlorinator

[bbillingsley1985]

So I have a pentair Rainbow Chlorinator 320 installed last year. I love it. Last year, I would put in 3-4 chlorine tablets, set the dial to the highest setting (which was 5), wait for it to fill up once I turned the pump on, close lid, and it worked like a champ. The tablets would last about a week so every Sunday I'd know it was about time to add more tablets. Other than occasional shocking, the pool always stayed within the proper chlorine ranges.

This year, I opened the pool in April and the pool temperature has been mostly 60 degrees. Planned to turn my heater on in May but just wanted it nice and clean and ready to go for when I turn the heater on. It took a few days to have crystal clear water after super shocking and everything has been fine (had an issue where pump was randomly shutting off, but solved that several weeks ago)....except I noticed that the chlorine was barely dissolving in the chlorinator. The same tablets I put in still had at least half life 2 weeks later. I had my pool 24 hours a day at medium speed (1725 rpm) because we aren't using it. In the summer I run it faster at times but since we weren't in it yet I figured that was unnecessary. Thinking maybe the pump just wasn't running fast enough, I thought ok maybe I need to run the pump faster for parts of the day. So I set it a little over a week ago to run it at 1725 for about 18 hours and then for about 2500 rpm for 6 hours a day. I used that all summer last year and it worked out fine. I put 2 more tablets in there so I had 2 half used 3" tabs, and 2 brand new tabs. One week later, I open the chlorinator and they still are mostly unused. Maybe 90% life left on the new tabs, and a little less than half life left on the now 2+ week old tabs. It was filled with water because the water drained when I opened it. I noticed the chlorine levels were low which prompt me to check it.

So I googled a few things and saw how I unscrew the line from the in/outs of it. I did that and cleaned it. It didn't appear to me that anything was clogged or in bad shape there. I removed the black piece at the bottom of the chlorinator and cleaned it good. It looked like it was in adequate shape, also not appearing clogged at all. Then I used my water hose and just sprayed all inside the chlorinator trying to clean everything I could. I then put the other 3 tablets in my actual pool skimmer so they can actually get used up, and left one of the newer ones in the chlorinator to see if maybe whatever I did fixed it. Does anyone have any idea what might be going on and if I should try something else?

A couple of info. It's a 22,000 gallon pool with a hayward heat pump (not turned on yet) and a vsp hayward pump with a waterco pre filter just past the pump as well as a cartridge filter. I confirmed that water is running into the chlorinator after I start the pump before I put the lid on. I let it get full, then I twist the lid on. When I stop the pump, I wait a few minutes, open the chlorinator, and it is still filled with the water. As I open the lid, all the water quickly drains through the bottom of it....seemingly to me showing that it is both receiving water and draining water. Does that seem normal on how it should behave? The only other thing at all that I noticed is if you google any picture of a rainbow chlorinator 320, the "in" line is connected at the bottom of the tower (and the top has a black seal just below the lid). My "in" line is connected at the top of my chlorinator with the black seal being on the bottom. In other words, that tube that comes from the very bottom where the main pool plumbing is, runs to just below the lid, and water shoots in from just below the lid. Is that setup right?

 

[HermanTX]

Your set up is fine - the line can connect to either the low or high port on the canister. There are 2 inherent problems with the chlorinator - one is that valve that controls flow from the main pipe to the canister. That can get clogged or just not work regardless if set on 1 or 5. The other is that there is a check valve in bottom of canister that allows flow only from the canister to the main pipe. That could be clogged so you are just filling up the canister but really have no flow through it. There is a 3rd problem which is the oring in the canister cap erodes fairly quickly due to all the chlorine which either makes the cap very hard to unscrew or it leaks.

The biggest concern is that at TFP we frown upon constant use of pucks. It drives up your CYA which requires you to keep increasing your FC levels to maintain proper sanitization. Have you reviewed ABCs of Pool Water Chemistry, Recommended Levels and FC/CYA Levels?? Best to spend some time with those documents as TFP is a different solution to sanitization vs what a Pool Store will tell you. For example, we never need to "shock" a pool if you maintain proper FC levels.

It would be better if you switch to liquid chlorine (LC). Do you have a proper test kit? Test Kits Compared
Test your CYA and see what that states - then compare that to the CYA/FC chart to see what you should maintain your FC level at to properly sanitize your pool.

Also - you should not place pucks in your skimmer. Purchase a floater for your pool. For those of us that use LC, the use of pucks are handy when away on a long weekend or so. This minimizes the use of pucks which can drive your CYA to unacceptable levels.

Good Luck.

 

[Toxophilite]

My pool came with that chlorinator, and I never got anything out of it. I could run my pump at 2900rpm with 4 tabs and barely get up to 2ppm for the day. After much back and forth, my PB swapped it out for a CMP Powerclean, which is designed for VSP's. Though it sits empty a lot, it's there and puts out chlorine if I use it. Even comes with a glass lid to see it work and a notional flow meter.

 

[bbillingsley1985]

Appreciate the responses from both of you. Herman, that is some really good information concerning LC. I appreciate the info and the links. After this season, I really think I might consider going to that or even salt water. Appears for a 22,000ish gallon pool I see some on Amazon for $1000-1500. Suppose I'd probably need an electrician too. Would somewhere in that price ballpark be reasonable or should I expect more? Any salt water systems you guys recommend that potentially can be a DIY?

On the issue with pucks, I've pretty much resolved to the fact that I need to use them at least for this season because when I got wind of the expected price hike 1-2 years ago I was able to buy 2 extra 40 lb buckets of the 3" tabs for around $100 per. I see they are more like $250-300 now. I have about 1 and a half buckets left which will last me this whole year so because of cost I will probably just do that until next year I do have a test kit and my CYA is right at 40 which seems good. I know salt waters need to be higher so perhaps the pucks will raise it enough to work with salt next year if I go that route?

As far as my setup, it really can't be simpler. Occasionally I add baking soda(maybe twice a summer) and other than that I put 3-4 pucks in the chlorinator every Sunday as well as about 4 ounces of this "bioguard all 60" non copper based algaecide. That's literally it. I have the 1 lb bags of shock that I maybe used 5 times last year after a big get together.

But back to my issue with the chlorinator. Toxo, I appreciate the suggestion to that chlorinator. I really like how that one looks. I may end up going that route if I can't fix this one. As far as the issue, since I verified that the line isn't clogged and water is easily getting in there, I guess it has to be a problem with the black rubbery seal on the bottom? The thing is when I stop the pump and open the chlorinator lid, it all drains out quickly seemingly making me think it's working. I checked today and it has just been about 2 days so hard to tell for sure but it seems like the puck really isn't breaking down. Should I try smashing it down and then putting it in or is that a bad idea. Also, the fact that these are about 1 year old shouldn't pose a problem right? They were kept in my dry garage that's insulated. All the way until I closed the pool last year, 3-4 pucks would last a week and completely dissolve. We are at the 3 week mark today on my initial picks and they still aren't fully dissolved.

I guess I can browse YouTube but is there any info on how to take that specific chlorinator completely apart? The black thing that pops out at the bottom I cleaned, but the small quarter sized rubbery thing at the bottom. I'm not sure if that maybe is clogged and I need to take that apart.

I know I can always just get a chlorine floaty deal instead but hate to do that since I shelled out however few hundred bucks to the pool company for the chlorinator.

 

[an1vrsy]

What is your pool water temperature? When I used to use pucks, they didn’t dissolve very well in cold water.

 

[bbillingsley1985]

It's been between 58-62 degrees mostly right now. This is also my first year managing it. I opened it a little early just to make sure it was all ready to go. When I started managing it last year, temp was already mostly in the 80s. Maybe that's the issue? I hadn't considered that. I plan to turn the heater on around May 1st and maintain 82 degrees + from there. Water is crystal clear and all is well, just annoying having to buy jugs of liquid chlorine and putting some of it in every few days to keep a little bit of FC level since the pucks are barely dissolving. Maybe as it gets warmer it will improve?

Looked at some videos on replacing the check valve at the bottom of the chlorinator. Part is cheap and it's easy to do.....just the thing is it drains super fast when I turn the pump off which makes me think that parts fine. I checked everything else so I really don't think the chlorinator is at fault....so maybe the lower water temps is making the picks dissolve slower? I appreciate the feedback.

 

[HermanTX]

Would somewhere in that price ballpark be reasonable or should I expect more? Any salt water systems you guys recommend that potentially can be a DIY?

Look at this site. Saltwater Swimming Pool Systems & Supplies | Discount Salt Pool
See the section on Brand Comparison. The lbs/day column is one of the data points I review to do a comparison but marketing tends to embellish what ratings of units are.

I know salt waters need to be higher so perhaps the pucks will raise it enough to work with salt next year if I go that route?

You can purchase salt which is really in expensive to raise salt when you install the SWCG.

 

[bbillingsley1985]

Appreciate the info Herman. That Brand Comparison link is extremely informative. I thought about posting here but since its in the wrong section, I made a new post in the salt section asking a few questions. Appreciate the help very much.

By the way, in case this helps anyone down the line, my issue with the chlorinator seems to be resolved. I did take the whole thing apart, noticed my valve at the bottom was clicking when shook, which indicated it was working. I hosed it all out really good and also increased my pump speed to about 2000 rpms instead of 1750. All of that in conjunction with warmer water temperatures as its warming up seems to be doing the trick. I'm willing to bet it was probably just the colder water temperatures.

 

[Toxophilite]

Thanks, I kinda came to the conclusion that the particular chlorinator was originally designed and used with much higher pump speeds and flow rates. Then, mine was trying to put out during the cold months of February and March on top of the cold. In hot weather, less dense tabs, I too might have gotten better results, but the PB bought and paid for the VS model and replaced it to resolve my issue. If would have had to pay for it, I would have saved the $$ towards a SWG, which is where I will be at some point soon.