Can I do this? SWG and Chlorine?

[bcrumb]

I have had an Aquarite SWG in my @8k Vinyl IG for several years now. I have recently become concerned with high power bills. I have to run the pump about 12 hours a day to keep the chlorine up, which seems like a waste of pump life and electricity. I was considering adding a chlorine injector to boost the Chlorine level and maybe have the best of both worlds. Has anyone tried this? Should I consider having 2 SWGs instead? I really would like to get run time down to about 6 hrs per day. Maybe I need a two speed pump. Any advice would be appreciated.
Bcrumb

[CarlD]

First, a two-speed pump will DEFINITELY cut your electric bill. I don't remember the exact numbers, but usually you can run it on low speed about twice as long for about 1/3 the cost. And it will run SO much quieter! I've had a 2 speed pump on my pool since Day 1 and would never be without one again if I have my druthers.

Second, where are you maintaining your FC level? And what is your CYA level? You can run an SWG pool at much lower levels for a given CYA than a regular pool. As WaterBear says, for a CYA of 100, you can run your SWG at 5ppm, rather than the minimum 8ppm the "Best Guess" table calls for.

Is your salt level sufficient? Your SWG shouldn't be running any longer than it needs to achieve the dialed-in FC level.

Post all your numbers and maybe we can see places to make your life easier and let your system run less.

[waterbear]

Please post a full set of test results and info on your pool and equipment.
How many gallons is your pool (sign says 8k) and which cell do you have? The standard T15 is sized for pools up to 40k gallons. However you might have a smaller cell.
I am particularly interested in your CYA level. If it is not 80 ppm then that is a major part of your problem (and also the pH control problem I know you will be having with too low a CYA.)
If your pool is omly 8k then you should be able to run the cell at a very low output and 8 hours run time should be more than enough to maintain proper chlorine levels. Whether you can cut your pump run time back is a different story that has nothing to do with the SWG. It is a function of your pump/filter combo.

[waterbear]

Please post a full set of test results and info on your pool and equipment.
How many gallons is your pool and which cell do you have? The standaard T15 is sized for pools up to 40k gallons. However you might have a smaller cell.
I am particularly interested in your CYA level. If it is not 80 ppm then that is a major part of your problem (and also the pH control problem I know you will be having with too low a CYA.)
It is possible that your cell is wearing out and near the end of its useful life and needs to be replaced if it is no longer producing enough chlorine. A call to Goldline customer support might be in order to check that out.

[bcrumb]

I have the standard T15 cell and it was just replaced last year. The pool is 28,000 gallons. I will post the numbers later as I am not home right now. Best I can remember my CYA is only at around 50. I thought I should keep it as low as possible because last year I had an algae problem and had to raise the chlorine to around 15ppm (per instructions found here) in order to clear it. I thought the higher the CYA, the higher you had to raise the chlorine level in order to kill the algae. I use a DE filter, Aquarite SWG. When the Cell went bad last year, I had to call Goldline(Aquarite). They told me that I should expect to have to run the SWG at 90 percent or above and that 12 hours would be the min I chould expect to get away with. Most times when I check the FCL, it is only around .5 to 1.0 ppm.

[bcrumb]

Forgot to say the salt level is good at 3200. Also, If you go with the 2 speed pump, what determines whether low or high speed is selected. You don't need a new timer/control box do you? I assume the pump itself has some sort of control device to select the speed and times.

[CarlD]

Nah, mine is simple: there's a toggle on the back of the motor. That's been good enough for me for 7 seasons, so far.

Rule of thumb: Low is normal, High is for vacuuming, backwashing, aerating, or when I want to get the most out of my solar panels.

[waterbear]

I have the standard T15 cell and it was just replaced last year. The pool is 28,000 gallons. I will post the numbers later as I am not home right now. Best I can remember my CYA is only at around 50. I thought I should keep it as low as possible because last year I had an algae problem and had to raise the chlorine to around 15ppm (per instructions found here) in order to clear it. I thought the higher the CYA, the higher you had to raise the chlorine level in order to kill the algae. I use a DE filter, Aquarite SWG. When the Cell went bad last year, I had to call Goldline(Aquarite). They told me that I should expect to have to run the SWG at 90 percent or above and that 12 hours would be the min I chould expect to get away with. Most times when I check the FCL, it is only around .5 to 1.0 ppm.
You need to run the CYA at about 80 ppm and keep the FC at about 4 ppm. Also lower the TA to about 70 ppm. This combo will insure that your maintain adequate FC in the pool without problems and give you better pH stability than you have now (it will lower your acid demand since it will allow you to GREATLY reduce the cell output). I doubt you will be able to reduce the pump run time below aabut 8-10 hours but I suspect the reason you cannot maintain chloirne is a nascent algae bloom. Shock the pool to about 20-25 ppm and I think you will find that the chlorine will start holding once you get your other water parameters in line with my suggestions.