Hayward T-15 output

[halleys5]

Greetings all,
I am about 3 months into a new T-15 and I am wondering if it is working correctly.

I currently have the % up to 75% and it is barely maintaining 3ppm. (20x36, 29k gals, 100% full sun, 60 CYA). The temp has been high for a few weeks now 90-95, all sun.

The unit reads 27V, 6.9A when running. The salt reading is low compared to the Taylor test (2700 vs 3200).
I'm having to add tri-chlor tabs to stay up in the safe zone if I do not run super chlorinate about every other day.

I'm guessing the next move is to do an overnight FC test to make sure I don't have something else going on, but the variation on the salt reading has me wondering.

Somewhere in the forum I had seen a daily output calc for the T-15, I believe it inferred I should be getting about 5.5ppm per day out of the cell, but I don't recall if that was running 100% or less. I guess I also need to find an estimator for FC loss with sun, temp and surface area.

Any other thoughts appreicated.

 

[trivetman]

Arr you running those percentages 24/7? If so something isn’t right.

Do the overnight loss test.

If that passes, do an overnight gain test with the swg on 100% for the night period.

My pool is a bit smaller than yours and I rarely run my t-15 at more than 50-60%

 

[Newdude]

You need to Overnight Chlorine Loss Test.

Once you prove there's no algae going on, then we raise the CYA.

Why did you replace the cell ? Same issue ?

The T15 will make about 5.9 ppm in 24 hours for you. 75% @ 24 hours is 4.4 and might be about right with a slightly lower CYA on a brutal heat wave week. If you aren't running 24/7 then it's even less and no surprise it's barely managing.

 

[halleys5]

Thanks all. You sparked a couple thoughts. I do have the variable speed pump running low for 12 hours, I thought it was still high enough for the SWG but I'll have to check.

I did some math as well, if I assume I'm losing 2/3rds of my FC on a full sun day, I would need to be adding 1lb to maintain. With the SWG only outputting 1.4lb in 24 hours, I would need to be set at just over 70% and flowing full time just to maintain. Throw in any disruptions, and I can see the issue.

And, this is a new pool, new equipment. I just stated it oddly at first..

 

[trivetman]

Put the vsp on low speed 24/7. Just high enough for the seg flow switch. It costs almost nothing to run the extra time and will give you a lot more flexibility with the swg output.

Do the overnight tests to make sure nothing is growing

 

[Newdude]

And, this is a new pool, new equipment. I just stated it oddly at first..

Ok GREAT.

if I assume I'm losing 2/3rds of my FC on a full sun day,

I wouldn't assume anything. UV loss can be all over the map day to day. You plan for the high UV loss days and accept that you'll overproduce on the other days. Most of any extra FC will be there for future use.

OCLT to prove we have time to fiddle with the rest. Report back with the results.

 

[halleys5]

Made another discovery this morning. I have the AquaPlus system, but don't use it for anything other than running the SWG. However, since I don't use it for running the pump and never set up the timers within, it was not "Filtering" 24/7 and therefore not running the SWG around the clock. I'm not sure what it thinks its doing the rest of the time, but it has to be Filtering to run the SWG. I'll have to reset up the timers to fix that for certain, but it does help explain why the Cl output seemed low.... it was..

The AquaPlus is a whole other story. I had grand visions for automated controls, only to find a mess of one-button configurations and no remote visibility of the system anyway. My pump has a 24 hour program that does the same thing and I have no solar heat or other frills that would run through the system. I did a roll-your-own for my heat pump control and I'm very happy with that vs the Hayward system that has no remote access (not by modern standards anyway).