Add SWG to my pool now? or wait till spring?

[Major_in_MS]

I've decided that I want to add a SWG to my pool. As this season is nearing end, I'm wondering if I will find discounted end of season prices on a SWG kit, or if I should wait till next spring to get the most out of the warranty.

I also would love advice on which unit to go with.

I'm also considering running my pump and maintaining my water balance through the winter as opposed to closing/opening my pool. In my area we will get a few days below freezing during the winter, usually into the high 20's F for a few days. Shouldn't keeping the pump running keep the pipes from freezing?

 

[YippeeSkippy]

That's basically what Skippy and I do- run the pump a few hours mainly at night . If the temp is below freezing for extended periods Skippy puts a tarp and moving blankets over the equipment pad and hang an automotive type light there (looks a tad sci-fi at O'darkthirty looking out at this dimly lit pod) and run the pump continuously until it warms up a bit.

Be aware that many of the SWG don't produce chlorine when the water temp is lower than 60 or so.. so you'll have to supplement with bleach but truthfully, the FC lasts forever when its so cold so that's not even often.

 

[Major_in_MS]

Thanks for the idea about the tarp/blankets and the drop light to heat the air around the plumbing on cold nights.

I'm still looking at the different salt systems, and I have no idea which one I should buy.

I don't have any type of pool automation equipment other than an Intermatic timer to turn my single speed pump on and off twice daily.



When I buy a salt cell or salt system will I need to buy a variable speed pump and controller and all that automation stuff? Or does the controller and automation come with the salt system?


Another question, It looks like Augusta, GA and Florence, MS are both in USDA Plant Hardiness Zone 8a which has a historical low temp in the 10-15 degree range. So since we share about the same winters, when can I expect my water temperature to hit the 60 degree mark? Does water temp lag behind air temps?

 

[GaryT58]

I had my first pool installed this year and live north or ATL (also in 8a) and will cover pool (have auto cover), but run pump and swg as needed over winter. I replaced my original SWG with an Autopilot TotalControl (75003) controller as I plan to add the PH/ORP control next spring. The Pool Pilot Digital is the same controller without the possibility to add the PH/ORP. This SWG has some good features like being able to automatically compensate the chlorine production based upon water temperature and turn on your pump when the water temperature is low (freeze protection).

Regardless of which SWG you go with, make sure you buy one that is larger than your pool. Sunlight will burn off chlorine quickly, even with cyn at higher levels. My pool has full sun for 8-9 hours/day depending on season, and the original SWG was running 24 hours/day at 100% and I had to supplement with liquid chlorine when the summer was peak (air temps in upper 90s, heat index over 100). Now that cooler (low 90s) the original SWG was able to keep up at about 65% (still 24 hours/day). The new cell is rated for up to 52,000 gallons, and my pool is 19,000. I have it set to 25% on the lowest cell power (can set cell to one of three power levels as well to increase life).

I considered waiting until next spring as well to replace, but pulled the trigger now, as I wanted the freeze protect feature (new pump had that as well, but will use SWG to control pump).

Whenever you choose, I would recommend Josh from saltpoolguys, a fellow TFP member, and he was great at answering emails for questions.

 

[Chuckiechan]

A suggestion : I added a separate Intermec timer for the SWG to give me more control over run times.

 

[JoyfulNoise]

A single-speed pump with an SWG is the least optimal way to do it. SWG's only produce chlorine when there is water flow and most have a lower flow rate limit of 20GPM (some as low as 15GPM). So it is typical for SWG pools to run their pumps a lot longer than manually chlorinated pools. Since the SWG will be a stand-alone purchase, you might also want to consider upgrading your pump motor to a 2-speed motor sized so that the SWG can run at low speed. 2-speed motors are fairly cheap and, if you produce chlorine at the low speed, you will save yourself a lot on electrical costs. A variable speed pump is the most optimal way to go but not on your wallet - VSPs tend to be a lot more expensive versus just a motor swap.

If you did swap to a 2-speed motor, you would need to redo your electrical wiring and upgrade your intermatic timer to one that can control both low and high speed. Also, it is safest to always slave the SWGs power supply to your pump motor timer. The reason being is that you NEVER want to have your SWG energized if the pump is not running. SWG's have flow switches in them to cut off the SWG at low flow but that is a fail-safe mechanism, not an operational control device. While some may suggest that it is ok to use a flow switch in that manner, it is not safe to do so. An SWG creates both chlorine and hydrogen gas in an unseparated cell configuration which means that both gases are present in the water stream. Chlorine dissolves into water rapidly while hydrogen does not. The hydrogen gas will be seen as tiny bubbles coming out of a return. The danger in running an SWG with no water flow is that, if the SWG accidentally energized, it will create a mixture of hydrogen and chlorine gas that can build up in the pipes. That is an explosive mixture and there have been cases of people walking out to their equipment only to find that the SWG is blown apart.

Be safe and always slave the SWG input to the pump timer.

You can check out this website for a full market comparison of SWGs - Full Market Comparison of Salt Water Chlorine Generators for Swimming Pools

 

[Poolsean]

As GaryT58 said, the AutoPilot 75003 and DIG-220 units are capable of controlling your circulation pump, WITH a freeze protection mode that will turn your pump on and run continually, whenever water temperatures fall below 40 degrees. Moving water through your system will prevent freeze damage.
You will not need to upgrade to a variable speed pump (or two speed). If you do, you should run at higher speeds during the colder months. Low speed can allow the water to freeze still.
The Automatic Temperature Compensation feature, only found with the AutoPilot units, will automatically adjust your output, based on water temperature changes, and does not shut off due to cold water conditions.
I don't want to get into a "sales pitch" but just adding to GaryT58's response.

 

[JoyfulNoise]

Major,

You'd might be interested in reading these two threads -

The Physics of Freezing and Freeze Protection

Winterizing Warning!

The short answer is this - given your location and typical winter weather conditions, you're at very low risk for water freezing in your pipes. The first of those threads basically shows that it would take extended periods of time at below freezing temperatures to be of any concern for stagnant water in standard PVC pool piping. In the 2nd thread, chem geek basically shows that any amount of water movement in a pipe will make it nearly impossible for water freeze unless the temperatures are far, far below freezing -

Given usual rather fast water flow rates through pipes and most especially if the pool water was not near freezing in temperature, it would take an extraordinarily low temperature to cause freezing of moving water in the pipe.

So even on theoretical low speed pump setting, your plumbing would be fully protected. As a personal example, in the winter my pool water will get down into the low 40's (~38-42F). When the air temperature drops to near freezing (~34F), my automation system turns on my variable speed pump. I have it setup so that it turns on a separate circuit with an extremely low speed set (~1100rpm on the pump and ~200W of electrical power draw). Given the head loss in my system, that speed setting causes barely a trickle to flow from my returns (you can just barely feel the water coming out of the pipe). My pipes are fine and I have never had any freezing issues.

In case it wasn't clear, I was not implying that you had to switch out your pump motor, only that it would be a good idea to do so given the fact that SWG pools run their pumps as much as 2X more than manually chlorinated pools. 2-speed motors (you'd only swap the motor, not the wet end) are very cheap (less than the cost of a new SWG) and, if redoing some electrical work at the equipment pad isn't too costly, a 2-speed motor is a great way to save on electric utility costs. Obviously up to you based on upgrade cost, but we've had a number of threads here on TFP where folks install an SWG and then they're perplexed (and upset) at why their electric bills are so high...most simply do not realize the added cost associated with having to run the pump with the SWG.

 

[GaryT58]

In my case, I am replacing this weekend my 1 hp single speed pump with a variable speed. The savings of being able to run at a low rate, as my new SWG will only need 15-20 GPM is quite large. I will run 24/7 for about $5 month as compared to the $100 with the 1 HP. So going to at least a 2 speed will save you a lot. I personally want my pump to run 24/7 so I have constant water flow and cleaning. I realize I may be in the minority. Oversizing the SWG will also allow you to run the system for less time too.

I set my system when installed to 25%. The nights are getting cooler and I see that the SWG automatically lowered itself to 17% as the water cooled. So that was nice, I didn't need to do anything.

 

[isriam]

don't buy it until next spring. you won't need it all winter long and you'll just be wasting warranty.

 

[pooldv]

That's pretty good advice. I shut my SWG off when the water drops below 70 and switch to bleach.

 

[Major_in_MS]

I want to thank everybody for their input on this thread.

I have decided to wait till spring to make my final decision on which SWG/pump/automation system I want to buy.

 

[Sweep49]

I want to thank everybody for their input on this thread.

I have decided to wait till spring to make my final decision on which SWG/pump/automation system I want to buy.

That's a good decision to wait.

I wanted to chime in about closing the pool or keeping it open. The first year we had our pool, I closed it and found it to be a lot more work than just keeping it open. There's all the work of filling water bags and putting the cover on and taking it off again. But also, through the winter I had to pump rain water off the pool cover and contend with mosquitos breeding in the standing water. We live in SW GA, so a climate similar to yours. Also, we have leaves from the water oaks accumulate on the cover through out the winter which is another pain to deal with when removing the cover.

So, the next year and since I have just left the pool open and it's a better way to go IMO. When the water temp gets into the 50's, I pull the swg and install a bypass pipe and goto bleach for about 3 months. I have a 2 speed pump, so on cold nights I will run the pump over night on low speed to prevent freezing. I don't have automation, so just do this manually with the timer when the weather forecast dictates.

Finally, instead of looking at a covered pool with rain water and debris floating on the cover, we get to look at the sparkling pool water through out the cold season. Hope this is helpful.

 

[mguzzy]

I did my SWG in the off season so I could start up with a new system in the spring and open the pool with SWG type chemistry. It is a tad different that non-SWG chem, you can read up on it in the chem section of this site. (I also replaced a bunch of stuff at the same time). As I watched the prices of most SWG systems over the course of the year they seem to go up and down. It seemed to me to be cheapest around mid summer. Probably because there is a surplus of products that haven't sold yet, is my guess. Someone else my have a different observation on prices.
Mark

 

[isriam]

Yea, I also looked around, and ended up purchasing in Feb/March. I found in August, prices went up, which was really weird. They stayed up all winter, and then dropped in Spring. It was not what you would expect, like summer clothes or the like.