Pre-SWG Install / Determining SWG/Pump run time

[Lostinthesauce]

Hey guys,

Well I close on my house on Monday, and I just got my Circupool SI-45 in the mail today. Got the whole week off from work to move and do some work, so I'm probably going to try to install it sometime next week. I've already got the T-100 test kit and the Taylors salt water test kit ready to go, so figuring out what I've got and what I need to do to get the pool in good shape shouldn't be that bad... hopefully. Pool has been crystal clear and well taken care of, so I hope I don't find something majorly out of wack when I get to test the water on Saturday. Hoping the age of the pool will also help me on how much salt I WON'T have to add to get me up around 3500ppm.

I've got a few questions after reading some articles around the site.

First, do I want to get my CYA levels to normal pool level or SW levels before crank up the generator? Or does it even matter? I was planning to try to get it up to 70 CYA and 5 ppm FC before I started to rely on the SWG.

Second, I'm down in Houston, so I should loose 1-2 FC a day from what I understand based on the pool being right. My pump will need approximately 3 hours 20 minutes to turn the pool water over once, and I'll generate approximately .4998 ppm FC per hour with the SWG. (20000 gallon pool with circupool saying it makes 2.0lbs a day...). I'm planning on doing 6 hours of run time a day at 100%, three hours at night and three hours probably around noonish, which should give me almost two full turnovers and 3ppm chlorine. I plan if I have a higher swim load I will just run the pump with folks are over to deal with that.

Based on my math (which may be complete wrong), do you think this will be sufficient for normal maintenance chlorine generation?

Am I all jacked up? or good to go?

 

[jblizzle]

Start with a full set of test results. And we can form a plan from there. You CYA may already be way too high for all you know at this point.

You may need more that 2ppm each day; really comes down to trial and error. I think 6 hours run time is a good starting run time, likely will not need it at 100%, but you can dial it back.

Have you read the Determine Pump Run Time article? Turn over does not really matter.

Certainly consider replacing the motor on your pump with a 2-speed when you need to in order to save yourself some money on power.

 

[Griswald]

In NC, I run 20% for 12 hours. So 40% for 6 hours may be enough. My pool is covered so thst makes a big difference. Before the cover, my CYA was low and I ran 12 hours at 80% and barely kept 2 ppm.

 

[timerguy]

My calculaions say running your swg for 6 hrs @ 100% should produce ~3.2 ppm FC in that 6 hrs. That may or may not replace what is being burned up by the sun every day. You'll have to determine that by experience. Easy enough to tweek the swg. Make sure you check your existing salinity level before you start adding salt. I'd put the salt in a couple days before you're going to be ready to start the swg. You'll enjoy having that si-45.

 

[Lostinthesauce]

So I was able to actually get the SI-45 installed yesterday, after a week of draining water to get my CYA and CA down. When I got the pool last monday, the FC was over 40, CYA was completely untestable, and my CA was over 800. Lets just say the pool got a lot of new water. It was an older couple that knew I had never had a pool before, so I'm guessing they shocked it, and the two floating chlorinators full of pucks were just a housewarming present to keep away algae. I got the water leveled off getting consistent readings of 8-10 FC, 60 CYA, 325-350 on CA on Friday and I maintained over the weekend. All I have to say is THANKS TO EVERYBODY who posts on here. A TON of help.

The SI-45 was actually an easy install. I had a reasonably easy portion of pipe to install it in prior to the pool/spa split. For a one man job, not bad at all, but I also did have a timer already wired in... Haven't done PVC in a long long time, and still no leaks.

I tested yesterday after doing some test running for leaks. After I tested the water, it ran the timered 3 hours in the evening (8-11) last night, and 3 hours in midday (11-2) today.

Yesterday Today
@1800 @1730
FC 6.5 FC 8
CC <0.5 CC <0.5
Salt 4000 Salt 4200
CYA 60 CYA 60
CA 325
TA 130

I drain / return into both pool and spa unless I'm heating up / in the spa, so the readings are consistent in both pool and spa. So I've got a 1.5ppm increase in 24 hours. Sun wasn't really out today all day today. I figure I will let it run another 24 hour cycle, test again tomorrow, and if I continue to see the increase, I will back it off until i can get it leveled off.

I'm running at 100% and think I will decrease my run time instead of bringing down the percentage... Less time on = less kw/h's the pool pump is eating. If I can get buy running the whole thing three hours a day, and then when I have a high swimmer load, I will loose it. I don't think I'm going to get that lucky however.