Generator Sizing

Mr. Fixer

Bronze Supporter
Apr 25, 2017
13
LIBERTYVILLE Il.
#1
Hello all,

I'm looking at a SWG rated for 35,000 gal. My pool is an 42'x20' AG Aqua Leader pool. The pool calculator tells me my pool is 25,400 gal. I've read you should over size the SWG for longer service life and shorter run cycles. Given my pool size, will a 35k SWG be adequate to achieve those two goals?
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
10,514
Bedford, TX
#2
M,

Welcome to TFP... A Great resource for all pool owners worried about size... :snorkle:

We recommend a SWCG that is 2 times the volume of the pool. So, for a 25K pool we would recommend a 50K SWCG..

As far as I know there are no 50K SWCGs, so that would mean moving up to a 60K model...

Here is why we recommend always having a larger SWCG than you need... SWCG ratings are based upon running them 24/7, at 100% output. I doubt you really want to run your pump 24/7.

A 35K rated SWCG will have to run much longer to generate enough chlorine for your pool than a SWCG rated at 60K.

Thanks,

Jim R.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#4
40K cell is about the minimum I would suggest and would likely need to run at 100% for about 11 hours every day.

If you do not have a VS pump that is going to cost you a lot electricity..
 

LapPoolMike

Bronze Supporter
May 13, 2017
130
Saint Petersburg, FL
#5
Mr. Fixer,
I'm in Florida, my pool is 29,900 (call it 30K) gallons, and is in full sun from morning until late afternoon (when the house starts to shade pool). So my pool size is in the same ballpark as your 25.5K pool. I have the Pentair IC40 rated for 40,000 gal. My CYA is at 80 ppm. Right now my FC daily loss is about 2 ppm, and I need to run my IC40 cell at 100% duty cycle for 9 hours/day (10am-7pm) to keep up and keep FC at 6 ppm. I'm worried that this cell won't have enough capacity once "real" summer hits, I'll just have to run it longer. I wish I had the IC60 cell, but I got what the builder gave me! Luckily I have a VS pump that draws only about 300 Watts at the speed required to run the cell. Good luck!
 

Mr. Fixer

Bronze Supporter
Apr 25, 2017
13
LIBERTYVILLE Il.
#7
After physically measuring my pool depth and finding it to be 48" not 54", I recalculated my pool volume to be 22,600. Do you think a 40k SWG would be sufficient given the decreased volume ?
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
41,197
Tucson, AZ
#8
That is really only a 10% volume decrease so you would just be able to decrease the run times I reported by about 10%.
 

bmoreswim

Gold Supporter
Platinum Supporter
LifeTime Supporter
TFP Guide
Jul 16, 2012
4,309
Central MD
#9
In IL, as in MD, 1.5x is fine. The sun isn't as strong and you will not have to run as long as noted above. It is different than lower latitudes.

I rarely get above 50-60% for 12 hours. Which is only operating it for 1/4 of a day. I could run it at 100% for fewer hours but I like the additional skimming time.

This is with my 70-80 CYA levels. Absolutely no harm in going bigger though.