Hi there. So our cell wasn’t producing at 100% so we replaced it with a 40k. My husband read all the instructions, plus some from the internet. It’s like a plug and play cell - for an AquaRite system. Anyway, my question is: Should a brand-new cell have to be run at 60%? We have been monitoring the pool FC like a mama duck sitting on eggs and we have had to help it at first while figuring out what percentage. 60 seems to be right to maintain 6 FC. We were told that if we got that cell we would only have to run it at 20-30....just wondering
New cell - went from 20k cell to 40k
- Thread starter DMS2014
- Start date
- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
You have a 20000 gallon pool. The 40000 gallon rated SWCG will need to run at ~50% for 24 hours per day to chlorinate your pool in summer.
What CYA level are you using?
What CYA level are you using?
The cell is always rated to handle the gallons of the pool if it runs 100% of the time. A 20k on a 19k pool would have to run almost all day to do its job properly. In Texas, in August your FC demand would be the highest of the season and it may not be able to go above and beyond to keep that higher demand for the peak season. Doubling the cell like you did would afford you am approximate 50% runtime but being the peak demand season, Having to run it at 60% is very possible.
Also, early and late season with less demand you won’t have to run it nearly as much. I start at 20%, move to 40% as the season heats up, then need 60% for the hot part, and then start dialing down for the back half. It fluctuates based on the UV index from the sun which is basically correlated to air temperature. It’s a different measure but the 2 usually go hand in hand. It’s not a ‘set it and forget it’, But more of a ‘set it and it will be good for a few weeks’
Is that because the OP is in Houston, Tx. Just asking since my pool is 20k with a 40k SWG cell and I run at 30%.
Last edited:
Everybody’s mileage may vary due to region, the amount of shade a pool has, or CYA levels.
- Nov 12, 2017
- 11,933
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Great. Test your FC every day for a week and see what your FC loss is per day based on what your SWCG is adding to your pool. This time of year, in Houston, you can easily use 4 or 5 ppm FC per day.
Today our chlorine was down by 2ppm. It’s going down every day. We are trying to find that sweet spot. I find algae unlikely as we have been on top of the FC since we got rid of it last month..didn’t want to go down that road again!
- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Good to know. We have been checking it every day or every other day bc we didn’t want to go down the algae road again...
No. 12 hours. That is what our pool person set up - 9-4 the rpm is higher. So he has it set at 1875 7 to 7 and 2500 9-4. Sorry didn’t see this post before I posted the other.
- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
At 12 hours, your SWCG should be set at 100% to start. That will create 4.4 ppm FC per day. You current setting of 60% is way too low.
- Nov 12, 2017
- 11,933
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
This is what works for me when seeking the optimum % for my SWG. I do this at the same exact time of day, every day until the SWG is setup correctly:
- I test FC and use the result and Pool Math to determine how much liquid chlorine, if any, to add to move my FC to my Target FC level (based on my CYA, of course).
If Pool Math indicates my FC is high, I adjust the SWG % down and repeat this all the next day (same time).
If Pool Math indicates my FC is below my Target FC level, then:
- I add the recommended amount of liquid chlorine to move my FC to my Target FC level.
- I turn up the SWG % a bit (maybe 5 or 10%, depending on how far off the FC was).
I repeat this process daily until the FC remains stable at my Target FC level.
The trick is to move the FC level each day using liquid chlorine when the FC is low. If you try to move the level with the SWG alone, you'll get into a ping-pong-roller-coaster ride and it'll take you a lot longer to find the setting. SWGs are great at maintaining FC, not so great at moving the FC level.
- I test FC and use the result and Pool Math to determine how much liquid chlorine, if any, to add to move my FC to my Target FC level (based on my CYA, of course).
If Pool Math indicates my FC is high, I adjust the SWG % down and repeat this all the next day (same time).
If Pool Math indicates my FC is below my Target FC level, then:
- I add the recommended amount of liquid chlorine to move my FC to my Target FC level.
- I turn up the SWG % a bit (maybe 5 or 10%, depending on how far off the FC was).
I repeat this process daily until the FC remains stable at my Target FC level.
The trick is to move the FC level each day using liquid chlorine when the FC is low. If you try to move the level with the SWG alone, you'll get into a ping-pong-roller-coaster ride and it'll take you a lot longer to find the setting. SWGs are great at maintaining FC, not so great at moving the FC level.
Okay, y’all, here’s what I am having trouble wrapping my head around. Our previous SWG was a 20k unit that we had no problem with until we had a problem. So now we have a 40k and yet we can’t get the FC stable. I went out there just now and it’s down to a 3. I just added CL to make it go to 6. I don’t understand how our previous pump settings (that we’ve never changed in 6 years) now have to be changed ???? AND it’s not making enough FC....i just don’t get it. This pool has been a PITA this year....i am sick to death of testing the FC every day. I can show you the logs. I’m filling out my log book that I’ve had since day one.....sigh...
Chems Monday were: 4, CH 400, TA 90, pH 7.8, CYA 70. We still have the continuing pH issue but right now, getting the FC stable is my main priority.
Chems Monday were: 4, CH 400, TA 90, pH 7.8, CYA 70. We still have the continuing pH issue but right now, getting the FC stable is my main priority.
- May 3, 2014
- 58,745
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
- Jul 16, 2012
- 7,211
- Pool Size
- 27000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Did you change the setting on the system to tell it you now have a different model # cell? We have Hayward Prologic and you have to set what cell you are using. I'm not sure if you just have the Aquarite if that's the case also, but I suspect it is.
And along Marty's line of thinking, comparing to something previous is not always worthwhile. You are trying to run it for 7 hours at 60% - too little time. Said another way, you are generating enough chlorine for a 7K gallon pool. (60% x 7/24 x 40K )= 7K. Clearly too low for a 19K pool. The temptation to compare is there, but you have to focus on what it it should be able to do and not introduce other issues.
And along Marty's line of thinking, comparing to something previous is not always worthwhile. You are trying to run it for 7 hours at 60% - too little time. Said another way, you are generating enough chlorine for a 7K gallon pool. (60% x 7/24 x 40K )= 7K. Clearly too low for a 19K pool. The temptation to compare is there, but you have to focus on what it it should be able to do and not introduce other issues.