Just curious

[FlpoolRob]

I have a 11,800 gallon pool in central Florida. I have the Pentair IC20 SWG. my equipment is under a three year warranty with 1.5 years left from the pool builder. I run the SWG at 80% for 8 hours a day to maintain FC. Does that sound reasonable?

I swear last summer I didn't need to run it over 20% and it maintained FC just fine. Earlier this year I had to call the builder to have them look at the SWG because the flow meter stopped working. Part of me thinks they swapped out my SWG with a rebuilt used one. I didn't pay much attention last year to which model I had. I think those shady jerks swapped in an IC20 for an IC40.

 

[JohnT]

How does your CYA compare this year to last?

 

[FlpoolRob]

Right at 75. Same as last year.

Also I have been doing an OCLT for the last three nights and no drop in FC at all. No CC either.

Here are my numbers:
FC 6.5
CC 0
TA 80
CYA 75
CH 380
PH 7.5

 

[linen]

Are you having to clean/backwash your filter more often this year?

 

[FlpoolRob]

I don't think so. I have a cartridge filter and clean it every two weeks.

 

[JamesW]

The cell should have a label identifying the cell type.

 

[FlpoolRob]

The cell should have a label identifying the cell type.

The one I have now says IC20 on it. I never payed close attention to the label before so I don't know if it could have have been an IC40.

 

[linen]

Out of curiosity, what size filter do you have?

 

[FlpoolRob]

Filter is 100 sq ft.
Just checked the OCLT and still at 6.5ppm

 

[linen]

As you probably already know, that filter is undersized for your pool.

Just to check, the swg was off when you did the OCLT?

 

[FlpoolRob]

Yes the SWG was off. I was wondering about that. I'm thinking about calling Pentair and letting them know what this pool builder is doing to customers. It makes Pentair look bad when an irresponsible builder cuts corners with their equipment.

 

[FlpoolRob]

I just looked up the spec for my filter (Pentair CCRP 100) and it says 48000 gal turnover in 8 hours. That looks like the right size to me.

 

[linen]

What is the correct sized filter?

tfp recommendations would be a minimum 188 sq. ft. cartridge filter for your size pool. I was just asking as I was thinking about a latent algae growth that could be causing your swg to work hard (and would have caused you to clean the filter often). However, the OCLT should have shown that.

 

[FlpoolRob]

What is the correct sized filter?

tfp recommendations would be a minimum 188 sq. ft. cartridge filter for your size pool. I was just asking as I was thinking about a latent algae growth that could be causing your swg to work hard (and would have caused you to clean the filter often). However, the OCLT should have shown that.

That was my first thought as well. I just got done with a week long mustard algae slam and finally killed everything. I cleaned the filter right at the end of the slam while FC was still in the 40's. I have passed the OCLT every night for the past 4 nights that i have been measuring. I am going to try cleaning the cell again (I cleaned it prior to the slam about 2 months ago) and see if that helps. I'm thinking about rigging a camera up to record the cell lights for a typical running day to see if the cell is doing something funky in the middle of the day.

 

[linen]

If you can easily see the plates, and the gaps between them, I would look at it before cleaning it again, just to be sure it is warranted. As I understand it, cleaning the cell very frequently can take some life off of it.

How does your water look? Any signs of algae anywhere?

 

[ping]

I calculated out that the IC20 cell is producing close to 2 ppm of FC a day for your pool size at 80% for 8 hours and that is not out of the ordinary. An IC40 makes double the amount of chorine than the IC20 and you might have gotten by last year with those numbers. They might have swapped out the cell and given you a smaller one.

The cell that you have now seems to be working fine by my calculations.

 

[FlpoolRob]

My water looks great! Pool surface looks clean.

 

[FlpoolRob]

As a side note - Someone else on the forum (I forget who) created an excel spreadsheet to calculate the amount of CL created in a pool from the SWCG. I took it a step further, and I see now that yes, indeed, my SWCG is working as it should. Thanks for all the help and I will share what I added to the file for the rest of the community.

[attachment=0:2r6f2fx1]SWCG_Settings and CL Calculation.xls[/attachment:2r6f2fx1]

 

[bobodaclown]

thanks.