Startup SWG chlorinator salt for new pool

[FIESTA62]

Aussie SWGs

yes thats the way it works, but i can put a digital external timer on to start SWG which will then start pump, i need to read manual on that option, the new digital timer i have is wi fi so i can control and set times from my mobile, this could be a easy way to change run times while siting watching tv ...that sounds like me !

 

[Dirk]

so for run times i could put on a digital timer, manual says i can disable the SWG inbuilt timer and use external, then i could say run for 4.5 hours at 100% , but running 5 hours it crept up i wonder will knocking off 30 minutes be the answer, i guess thats all i can do, or try different times at the 75% output

OK, sounds like the SWG and pump are sync'd for safety, so check that off the list. Excellent.

And you have a good handle on the rest. Just watch out for one thing that might mess you up. And you'll need to check your SWG manual to see if yours works like ours do here.

If you run at 100%, then this is a non-issue. The SWG will be producing 100% of the time, and lessening the runtime by 10 minutes will give you 10 minutes less chlorine. All good. But if you try 75%, that might not work that way.

When I set my SWG for 50%, it doesn't make 50% less chlorine all the time, it makes the same amount it always does, but for only 50% of the time. It'll produce for 5 minutes, then idle for 5, then repeat. So if I lessened my runtime by 5 minutes, say from 60 minutes to 55 minutes, then it wouldn't make any less chlorine, because it wouldn't have been making any anyway.

So you need to figure out if your SWG has an on/off schedule like that, like 75% on and 25% off, and then find out what the on/off frequency is. Say, at 75%, your SWG makes chlorine for 45 minutes each hour, and then it idles for 15 minutes. Well, if you reduce the runtime by 15 minutes, you won't actually be reducing the chlorine output, because it'll still make chlorine for 45 minutes.

If your SWG has a faster cycle, like many do, then this won't matter much. Or if your SWG can dial down production by 25%, but still make chlorine for the full hour, then this won't matter either.

Just something to be aware of and figure into your runtime trials...

 

[mgtfp]

When I set my SWG for 50%, it doesn't make 50% less chlorine all the time, it makes the same amount it always does, but for only 50% of the time. It'll produce for 5 minutes, then idle for 5, then repeat. So if I lessened my runtime by 5 minutes, say from 60 minutes to 55 minutes, then it wouldn't make any less chlorine, because it wouldn't have been making any anyway.

I think, that's another difference of the Aussie models. Most don't seem to adjust chlorine output via duty cycle (e.g. 75% means 45min on 100% output plus 15min on 0%), but by actually adjusting the cell voltage and keep producing chlorine the whole time, but on lower output. At least the AstralPool models work like that, not sure about Watermaid.

@FIESTA62 : Do you have a clear cell housing, can you see what's happening inside the cell? Do you see bubbles being created the whole time when the SWG is on, or are there times without bubbles (i.e. no chlorine generation)?

Edit: Just added a not so important "don't"...

 

[markayash]

I think, that's another difference of the Aussie models. Most don't seem to adjust chlorine output via duty cycle (e.g. 75% means 45min on 100% output plus 15min on 0%), but by actually adjusting the cell voltage and keep producing chlorine the whole time, but on lower output. At least the AstralPool models work like that, not sure about Watermaid.

@FIESTA62 : Do you have a clear cell housing, can you see what's happening inside the cell? Do you see bubbles being created the whole time when the SWG is on, or are there times without bubbles (i.e. no chlorine generation)?

Edit: Just added a not so important "don't"...

My Edge40 does that also. I have a smart plug and it pulls less watts and stays there as long as it's running. I think the Core might also

 

[mgtfp]

There is a nice video in this post showing how the chlorine production inside the cell looks like for chlorinators that adjust the voltage to change the output:

For the benefit of future reference for others - I'll add on old video of mine to this thread as well.

A popular brand here Downunder (Astralpool) also allows the user to alter the DC drive level to their SWCG which allows you to adjust the chlorine gas output of the cell rather than controlling the overall output by switching a cell on/off at a constant 100% drive level. From my limited understanding... this method of controlling the cell's output does not seem as common in the US.

The video below simply shows the amount of gas being generated at various drive levels:

 

[FIESTA62]

cell creates 30g per hour (or 1.58 pounds per 24h), right?

yes thats the correct output it does, i called Watermaid they said the unit is always producing , just voltage drops , he suggested 75% at 5 hours for starters

u may have told me the way to calculate this before in one of my zillions of posts, but could you tell me how you calculate the 30 gram per hour/36000 into PPM using different percentages of output, u did calculations on different percentages, i am lost on this but it is something very interesting...

i just checked CYA its a cloudy day but looking at test outside, then inside under light i see 70 using Taylor test tube that's FC4....and 60 using Clear choice test tube thats FC 5, so its 60 or 70 so to be safe i assume use 70 as the level as it asks for more FC , better to be over a bit rather than under i assume......so target FC 5

as for leaves i get very little not much at all, pool stays pretty clean....

 

[mgtfp]

u may have told me the way to calculate this before in one of my zillions of posts, but could you tell me how you calculate the 30 gram per hour/36000 into PPM using different percentages of output, u did calculations on different percentages, i am lost on this but it is something very interesting...

Easiest is to use PoolMath. In the burger menu on the top left you pick "Effects of Adding". Enter your pool volume, and under "Chemical Additions" you pick "SWG" from the menu. Next line you enter the "24 Hour SWG Output" in pounds. You can either pick a model via the magnifying glass (there is a Watermaid in the list that seems to have the same output). You need to know that 30 gramm per hour is the same as about 1.58 pound per day (you can get that simply by googling "30 g per h to pound per day"). Then pick "Free Chlorine generated" from the next menu, enter SWG% and pump run time, and PoolMath will calculate how much chlorine in ppm will be created. With the other options you can also calculate how long you need to run the SWG to create a certain ppm on a fixed SWG%, or which SWG% is required to generate a certain ppm with a fixed run time.

That will give you a good estimate as a basis for fine tuning. You know that you seem to loose about 1.5ppm over 24 hours (which sounds perfectly reasonable), so that's what you have to produce per day to replace the losses and keep your FC constant.

The mentioned 5h@75% will create 3.1ppm (Edit: I just corrected this, had the wrong SWG picked) in your pool, a bit too much (but might have been what you needed around Christmas on very sunny days - that changes of course with cloud coverage and time of year, in winter you might need less than 0.5ppm per day).

 

[FIESTA62]

Effects of Adding

oh thats it i forgot, i think u or another member told me about "effects of adding ", i only used it once and forgot about it, ok so i gave it a go, it says 5 hour @75% is 3.1 as u said and going by my tests so far that's too much, i am assuming its not a perfect calculation just a guide, so i looked at other options and see 5 hours at 50% makes 2.1, that might be a good place to start, so i will try that and not bother with external timer at this point....thanks again

 

[mgtfp]

No worries.

That sounds like a plan. 50% could work. Each additional hour on 50% gives you about 0.4ppm. With that, you should be able to find something that works. If it turns out that you need less than 1.5ppm (could well be with a cover that's on for most of the day), you might have to go down 25%.

But start with 2.1ppm and see where that gets you after 2 or 3 cloudy days and after a few sunny days. Much safer to experiment on a higher level.

 

[Dirk]

yes thats the correct output it does, i called Watermaid they said the unit is always producing , just voltage drops , he suggested 75% at 5 hours for starters

Excellent. So one less thing to worry about.

so to be safe i assume use 70 as the level as it asks for more FC , better to be over a bit rather than under i assume......so target FC 5

Yep! In that case, I would treat FC 5 as my "artificial minimum" and never let it get below 5. FC 4 would be treated as an emergency that needs immediate attention. I might up my FC target to 6 or 7 so that a big party of swimmers or a very hot day does not overwork my SWG and let me slip below 5...

 

[FIESTA62]

ok so this morning cloudy day 8.am tested FC 5, using 70 CYA as pools level, so right on target, swg started for 5 hours at 50%, i intend on getting it around 6 just for that buffer.......TA 110 PH 7.6 will see how it goes over the next week of testing and get back here with happy results hopefully

 

[mgtfp]

Did that get to 5ppm (from 7.5ppm) with the SWG off? You had the SWG off for two days, the first day it went from 9 down to 7.5 (minus 16%), and then from 7.5 down to 5 (minus 33%, and you said it was cloudy). That worries me a bit that the chlorine loss is accelerating, and that you have more than 30% chlorine loss on a cloudy day with a pool cover.

As I mentioned earlier, the low SWG minimum only works because of the regular chlorine production and the super chlorination within the cell. You are at the non-SWG minimum now with the SWG off and your chlorine loss is accelerating, that might already be a sign of algae.

I really recommend to understand how your SWG ticks on a higher FC level, and then approach your target from above, not from below.

 

[FIESTA62]

Did that get to 5ppm (from 7.5ppm)

hi, yes i was 7.5 on tuesday morning the 5 on wednesday morning so more than i expected too, i was thinking around 6 would have been the level, i did not turn on for the day as i thought 7.5 is ok and if it drops to 6 then thats a good base point, 1ppm above target on a non-minimum swg, i thought that would be spot on, but 5 yes i hear u

its on at 50% for 5 hours today 3 in morning 8 to 11 and 2 hours afternoon 2 to 4 , its off at 4pm, CYA 70, so target is 5 but i am going to aim for 6 , i will always aim for 1 above target based on CYA, i will test after sun is off pool around 6pm, if its below 6 i will add liquid chlorine exactly what pool math says to get FC 6, , then test again tomorrow morning

i know i took a bit of a gamble leaving swg off but thought at 7.5 i have a buffer , its close but i assume or hope its still ok....

 

[markayash]

Go higher on FC, no disadvantage to how it feels..

I can't wait for my water to warm up so I can get mine running..Last check was still at 50

 

[FIESTA62]

FC 5 830am, 5 hours at 50% , FC 6 6PM, cloudy part sun day, 5 is target for 70 cya , i have it at 6 now, some say go higher for buffer but its 1 higher already, if i go even higher wont it just burn off and be wasted as CYA isn't protecting it

i understand on a really hot day it may not be FC6 at sundown, if it does drop below 6 at any point i will up hours from 5 to 6

TFP say target 5 with minimum 3, so 6 should be fine ?

if it spikes to 7 or 8 i wont worry but thinking average more at 6.....what do u all think?

 

[Dirk]

Six sounds fine. I won't get into the nitty gritty with you. You're finding your way. I described one way to stay out of the green, by running FC a little hot. And you're right, that if you go too high you'll just be burning off chlorine. I suppose I do that sometimes. That's my trade off for a little piece of mind.

Another way to go, which I also use, is to forecast high chlorine demand and use liquid chlorine proactively. Say you get your SWG dialed in so that your FC is good at the end of the day after normal temps and normal swimmer load. But then you get a forecast for a crazy hot day, or you've got a pool party scheduled with a bunch of kids, or both. So in the morning of such a day, you leave the SWG alone, but you just goose the FC with some liquid chlorine. Maybe a point or two, or three, whatever. You can even throw in a few extra cups when the kids take a break. If the party was especially brutal, you maybe test FC at the end of the day, or the next morning, and bring the FC back up to your target with liquid chlorine. Because you never adjusted your SWG, it'll just pick up where it left off.

So in other words, you don't have to run hot all the time for the few times you get extra demand, you run hot just on high-demand days. It's kinda up to you which feels like less trouble and/or is more cost-effective.

Always keep a gallon or two of liquid chlorine on hand. You never know when you'll need a quick boost.

You should be getting a sense that there is no one-size-fits-all MO. You learn your pool, and yourself, and tailor your regime to what works for you and your pool...

 

[FIESTA62]

Six sounds fine.

ok i hear what your saying and would do that, especially if it drops i wont wait for swg to catch up i will just pour some liquid in....

if i see it drops below 6 more than once and its just getting too tight i will do the 6 hours then i am sure that will be enough, but for now will see how 5 hours at 50% goes, starting up stepfathers pool tomorrow.....im the pool guy around here ha....

 

[mgtfp]

Looks like you are getting there. You got the basics now, from here on it's just gaining more and more experience.

Keep testing, don't forget about CYA from time to time. Don't freak out when FC starts to climb at some point in autumn. Days are starting to get shorter now and sun-intensity decreases because of lower sun angle. Where max UV-index in summer is usually well above 10, it is around 2 in mid winter. Together with the shorter day length, the total UV-load is easily a factor 10 smaller in winter, not even considering more shade on the pool with the sun hiding behind trees or the house. When you notice that, just start reducing chlorine production. I guess in winter you won't need more than 0.5ppm production per day. But keep the chlorine level at your normal target. Even though algae get's less active in winter, it is not completely inactive. You might not have to test often in winter, but don't miss the point when the days are getting longer again, and start cranking the chlorine production up again. You wouldn't be the first one to get a green surprise in spring because FC plummeted down to zero.

 

[Dirk]

I test once a week, all year round. No surprises here.

 

[FIESTA62]

looking good so far, FC6 last night.....FC 6 8am this morning.....weather is mild though so a hot few days might mess things up, i will check back in after a weeks testing ......