I've been searching for discussions on adding a second salt generator to my pool, but haven't seen much.. I know they exists as I see Pentair has a commercial setup where they parallel multiple SWGs in commercial applications..
My situation is pretty common. My Pentair IC40 just can't keep up when it gets hot and sunny (central Florida).. It does "ok" for most of the year although I have to run it at greater than 50%, but as soon as it starts getting hot, muggy and sunny, even running at 100% won't keep up. I will admit I was hesitant at first to run the CYA at the higher levels I am now (70-80ppm), and that did seem to help as I'm keeping more chlorine in the pool than previously. But a couple hot days and I'm having to supplement with liquid chlorine. I stay on it and have never had any signs of algae. I pull the cartridge from the filter every couple weeks and clean... Have swapped in a new cartridge as well.. Run a Dolphin robot a few times a week and keep the pool pretty much spotlessly clean. The pool is somewhere between 13000 and 14000 gallons.
This post is really intended to address how to best install a secondary SWG and not if I should needed to.. But since I'm sure the question will come up my pool chemistry is generally fine.. CYA ~ 70-80, PH is stable in range of 7.4 to 7.6, salt level ~ 3600ppm, Total alkalinity ~100ppm, CA hardness ~ 200... Have gone through the SLAM process periodically... Combined Chlorine is usually pretty decent and stays below 0.2 or 0.3 ppm. Any higher than that and I shock or SLAM the pool. I'm fairly confident in the chemistry numbers as I check daily both with regents and a Lamotte spin-tester. Pool isn't subjected to contaminates as it is in a patio screen enclosure so it doesn't see a lot of bug, leaves or other stuff..
For the most part the chemistry is good, the pool is clean and the water is clear.. The IC40 just can't keep up with hot days.. even though it is a relatively small pool. The IC40 is relatively new and seems to generate chlorine fine when it is not so blasted sunny.. So it appears to be functional. Also I've played with flow rates, and installed a mechanical flow rate indicator as well as I get flow feedback through my Pentair Easytouch on the GPM for the Variable Flow Pump. The IC40 seems to generate chlorine just fine above about 19 GPM (spec is min of 25 or 26 GPM). But I've been running my pump in the 30 to 35 GPM range to make sure low flow wasn't the problem.
So, chemistry wasn't the point of my post, but I figured I'd first go through that because I know the first assumptions was that I probably had a higher chlorine demand due to some pool chemistry or other incompetence with the SWG on my part. But I've had pools for a lot of years and never had chemistry or chlorine level problems, but I am new to Hot sunny Florida which places some pretty heavy demand on chlorine.
So what I want to do is add a second chlorine generator. I could replace the IC40 with an IC60, to get more generation capacity but figured If I have to buy another SWG, then I might as well use them both.. My Pentair Easytouch can only control one SWG, but I can manually control the second.. My plan is during the cooler season just run one SWG (as that currently works ok) and then manually turn on the secondary only during the hot months and try to balance the generation from the two to maximize cell life. In the end I want to get away from having to manually add liquid chlorine to the pool or having a floating chlorine puck duck..
So the question is... Should I be installing these in two parallel or in series? The Pentair commercial setup I've seen seem to put them in parallel. But if I put them in parallel then it means I have to run my pump at a higher (and much less efficient speed). So if the min is 25 GPH for one SWG to work, I'd have to run the pump at 50 GPH (which for my system works out to be about 2900 RPM) for both parallel SWGs to generate chlorine...
I know there is a concern with "bubbles" generated by the SWG, but I have enough room on my pad that I could spread the two series SWGs by 2 or 3 feet or more if needed.
I'm thinking I might run them in parallel, and have a blocking valve in front of the secondary unit, that way I only have to run the higher flow when I want to use both SWGs, so at least most of the year I can run the pump more efficiently.
Anyone have any real experience with multiple SWGs?
Thanks in advance.
My situation is pretty common. My Pentair IC40 just can't keep up when it gets hot and sunny (central Florida).. It does "ok" for most of the year although I have to run it at greater than 50%, but as soon as it starts getting hot, muggy and sunny, even running at 100% won't keep up. I will admit I was hesitant at first to run the CYA at the higher levels I am now (70-80ppm), and that did seem to help as I'm keeping more chlorine in the pool than previously. But a couple hot days and I'm having to supplement with liquid chlorine. I stay on it and have never had any signs of algae. I pull the cartridge from the filter every couple weeks and clean... Have swapped in a new cartridge as well.. Run a Dolphin robot a few times a week and keep the pool pretty much spotlessly clean. The pool is somewhere between 13000 and 14000 gallons.
This post is really intended to address how to best install a secondary SWG and not if I should needed to.. But since I'm sure the question will come up my pool chemistry is generally fine.. CYA ~ 70-80, PH is stable in range of 7.4 to 7.6, salt level ~ 3600ppm, Total alkalinity ~100ppm, CA hardness ~ 200... Have gone through the SLAM process periodically... Combined Chlorine is usually pretty decent and stays below 0.2 or 0.3 ppm. Any higher than that and I shock or SLAM the pool. I'm fairly confident in the chemistry numbers as I check daily both with regents and a Lamotte spin-tester. Pool isn't subjected to contaminates as it is in a patio screen enclosure so it doesn't see a lot of bug, leaves or other stuff..
For the most part the chemistry is good, the pool is clean and the water is clear.. The IC40 just can't keep up with hot days.. even though it is a relatively small pool. The IC40 is relatively new and seems to generate chlorine fine when it is not so blasted sunny.. So it appears to be functional. Also I've played with flow rates, and installed a mechanical flow rate indicator as well as I get flow feedback through my Pentair Easytouch on the GPM for the Variable Flow Pump. The IC40 seems to generate chlorine just fine above about 19 GPM (spec is min of 25 or 26 GPM). But I've been running my pump in the 30 to 35 GPM range to make sure low flow wasn't the problem.
So, chemistry wasn't the point of my post, but I figured I'd first go through that because I know the first assumptions was that I probably had a higher chlorine demand due to some pool chemistry or other incompetence with the SWG on my part. But I've had pools for a lot of years and never had chemistry or chlorine level problems, but I am new to Hot sunny Florida which places some pretty heavy demand on chlorine.
So what I want to do is add a second chlorine generator. I could replace the IC40 with an IC60, to get more generation capacity but figured If I have to buy another SWG, then I might as well use them both.. My Pentair Easytouch can only control one SWG, but I can manually control the second.. My plan is during the cooler season just run one SWG (as that currently works ok) and then manually turn on the secondary only during the hot months and try to balance the generation from the two to maximize cell life. In the end I want to get away from having to manually add liquid chlorine to the pool or having a floating chlorine puck duck..
So the question is... Should I be installing these in two parallel or in series? The Pentair commercial setup I've seen seem to put them in parallel. But if I put them in parallel then it means I have to run my pump at a higher (and much less efficient speed). So if the min is 25 GPH for one SWG to work, I'd have to run the pump at 50 GPH (which for my system works out to be about 2900 RPM) for both parallel SWGs to generate chlorine...
I know there is a concern with "bubbles" generated by the SWG, but I have enough room on my pad that I could spread the two series SWGs by 2 or 3 feet or more if needed.
I'm thinking I might run them in parallel, and have a blocking valve in front of the secondary unit, that way I only have to run the higher flow when I want to use both SWGs, so at least most of the year I can run the pump more efficiently.
Anyone have any real experience with multiple SWGs?
Thanks in advance.