Is there data to show that the larger cells last longer?

[UnderWaterVanya]

There are a couple of reasons to get an oversized cell, though the smaller cell will work just fine. The primary reason is that larger cells last a lot longer but don't usually cost all that much more, and so are generally a better deal. A larger cell also gives you more flexibility to cover relatively short pump run times and still produce enough chlorine.

Is there data to show that the larger cells last longer? If so does it give quantitative data to show when the price differential is warranted?

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[JasonLion]

Re: new SWG

The simple formula is that within a model line lifetime is proportional to the pool size the cell is specced for. So a cell for a 40,000 gallon pool will last twice as long (on average) as a cell for a 20,000 gallon pool when both are used in the same pool. In practice this is nearly true, though a few cells fail for reasons other than wearing out, so the actual lifetime ratio is just slightly worse for the larger cell.

All of this is true only when the cells being compared are designed the same way, use the same coatings, and base their pool size recommendation on the same formula. All of those factors are nearly always true when comparing cells designed by the same manufacturer to be used with the same power supply/controller, but not true when comparing across manufacturers.

 

[roth79]

new SWG

So done I will get the I 40 pentair, now I am looking at automation as I need to purchase that with the I-40, I am looking at the pentair easy touch but Im not sure so I will post that in a different forum, thanks all.

 

[bobodaclown]

Re: new SWG

Here's my take of the reason to over sizing.
The daily output is based upon a run time of 24 hours (how many people run their pumps 24 hours). So if your pools is less than the max rated, you "should" be good to go, but pool manufactures don't know your particular pool set up so it's based on averages.
If your cell is rated for 20K, and your pool is only 10K, theoretically you could run half the 24 hours or 1/2 the setting on the SWCG.
The major power user is the pump, so you want to run that as short as possible.
Now if you uprate the cell to 40K on a 10K pool you could run the SWCG 6 hours (1/4 of the 24 hours). Most pumps will provide 1 turnover of a 10K pool in that time.
The SWCG run time will also be effected by water condition (Salt level), and age of cell.
I believe that the cells are based upon 10000 hours at 100% output. They will last longer if run lower setting, shorter at a higher setting.
I definitely agree with JasonLion that it's a good idea to go with the larger cell when able.

Disclaimer: The info presented here is based upon my own observations and from information gathered from different sources. Your mileage may vary.

 

[UnderWaterVanya]

Re: new SWG

The simple formula is that within a model line lifetime is proportional to the pool size the cell is specced for. So a cell for a 40,000 gallon pool will last twice as long (on average) as a cell for a 20,000 gallon pool when both are used in the same pool. In practice this is nearly true, though a few cells fail for reasons other than wearing out, so the actual lifetime ratio is just slightly worse for the larger cell.

All of this is true only when the cells being compared are designed the same way, use the same coatings, and base their pool size recommendation on the same formula. All of those factors are nearly always true when comparing cells designed by the same manufacturer to be used with the same power supply/controller, but not true when comparing across manufacturers.

Ah OK - I was hoping there was actual data collected that could be used to analyze this but your point is rational. I also see the point about faster time to produce the needed FC which means shorter pump run times.

The "slightly worse" part would be nice to have quantified somewhere. The problem is how to collect that data.

 

[Pool Clown]

Re: new SWG

If you want data:
The iC15 produces (up to) 0.60 lbs. per day
The iC20 0.70 lbs.
The iC40 1.40 lbs.
The iC60 2.00 lbs per day of Chlorine.
All of these cells last about 10,000 hrs. or 5 years.
So you can see, and as others have posted, it's all about amount of plates or surface area thereof, and run time.

 

[UnderWaterVanya]

Re: new SWG

If you want data:
The iC15 produces (up to) 0.60 lbs. per day
The iC20 0.70 lbs.
The iC40 1.40 lbs.
The iC60 2.00 lbs per day of Chlorine.
All of these cells last about 10,000 hrs. or 5 years.
So you can see, and as others have posted, it's all about amount of plates or surface area thereof, and run time.

Actually this doesn't help really. What I wanted was some hard data that showed that the lifespan of the cell is a directly proportional function of the amount it is used. What you have posted is good info - but it doesn't tie that back together. I'd love to see a controlled study that showed that an IC40 lasted 10 years when used on a load that was appropriate for an IC20. Or more accurate data that showed an IC20 producing X amount of Chlorine / day lasts N days. The same amount per day produced by an IC40 yeilds 2N days (or some close fraction). I'd like to have quantified essentially that it works as expected and that failures due to other non-cell wear events is a minimal part of the equation.

 

[Pool Clown]

Re: new SWG

Actually this doesn't help really. What I wanted was some hard data that showed that the lifespan of the cell is a directly proportional function of the amount it is used. What you have posted is good info - but it doesn't tie that back together. I'd love to see a controlled study that showed that an IC40 lasted 10 years when used on a load that was appropriate for an IC20.

Me too! But there are too many variables that consume the Cl level at different rates over: days, weeks, seasons, temperatures, geographical areas, bather loads, rain, organics, etc. Which aren't even constant with one pool let alone every pool. Thats why there are different sizes of cells based on gallons. Thats probably the only variable manufacturers could tie cell size to that is a constant.

Or more accurate data that showed an IC20 producing X amount of Chlorine / day lasts N days. Again, the amount of Cl that a pool consumes changes from day to day (in some cases) and from season to season (every out door pool), The same amount per day produced by an IC40 yeilds 2N days (or some close fraction). I'd like to have quantified essentially that it works as expected and that failures due to other non-cell wear events is a minimal part of the equation.

I'll bet that even your pool doesn't use the same amount of Cl each day, month, trimester, throughout the year. So having said that, How could you decide on a size based on "scientific research"? Even if it was available? And if you did get an appropriate size, you would still have to adjust the output/run time throughout the year. Thus throwing out all the research.

Just get an iC40, you'll be fine...

 

[jblizzle]

Re: new SWG

While I agree that each pool will consume a different amount of FC in a given day, that would not affect the data UWV would like to see.

I think he is asking how the amount of FC produced (not consumed) affects the lifespan ... would an IC40 producing 0.7 lbs/day last twice as long as an IC20 producing 0.7 lbs/day. If so, that would certainly make a great case for going very large on the cell. As the lifespan of a cell would be #### lbs of FC over its life.

But, what this ignores though is how the pools chemistry is affecting the cell itself ... so maybe the lifespan is more tied to the amount of time it is exposed to the water. Meaning an IC20 and IC40 should function for #### amount of days ... but the IC40 could produce double the FC that the IC20 could in the same amount of time.

More than likely, the true life span is a combination of these possibilities ... amount of FC produced & # days exposed to water.

Of course at this point we are probably destined for the Deep End

 

[UnderWaterVanya]

Re: new SWG

While I agree that each pool will consume a different amount of FC in a given day, that would not affect the data UWV would like to see.

I think he is asking how the amount of FC produced (not consumed) affects the lifespan ... would an IC40 producing 0.7 lbs/day last twice as long as an IC20 producing 0.7 lbs/day. If so, that would certainly make a great case for going very large on the cell. As the lifespan of a cell would be #### lbs of FC over its life.

But, what this ignores though is how the pools chemistry is affecting the cell itself ... so maybe the lifespan is more tied to the amount of time it is exposed to the water. Meaning an IC20 and IC40 should function for #### amount of days ... but the IC40 could produce double the FC that the IC20 could in the same amount of time.

More than likely, the true life span is a combination of these possibilities ... amount of FC produced & # days exposed to water.

Of course at this point we are probably destined for the Deep End

You understand my question perfectly and I agree it's wandered into the deep end I'm afraid... sorry about that. I think manufacturers or independant testing could validate the assumed increase in lifespan via testing - this testing need not take 5 years results could be extrapolated if necessary. As for real world testing - perhaps a very large pool with multiple SWG's in parallel could be setup with some cells that are IC40 and some that are IC20 etc - then over time validation of the cell's performance could be recorded.

 

[Pool Clown]

Re: new SWG

While I agree that each pool will consume a different amount of FC in a given day, that would not affect the data UWV would like to see.

I think he is asking how the amount of FC produced (not consumed) affects the lifespan ... would an IC40 producing 0.7 lbs/day last twice as long as an IC20 producing 0.7 lbs/day. Yes, I think that while my post does not say that, it would suggest it. If so, that would certainly make a great case for going very large on the cell. As the lifespan of a cell would be #### lbs of FC over its life. I think with proper water chems that the cell output would remain what the manufacturer claims through MOST of the cells life. And i believe that over-sizing of the cell is SOP.

But, what this ignores though is how the pools chemistry is affecting the cell itself... Thats why you could never get accurate data throughout ... so maybe the lifespan is more tied to the amount of time it is exposed to the water. Not really, because the cell wont be running the whole time it is exposed to the water, i.e. when the pump is off, it is still exposed to the water, or in your example running at 50%. Lets not forget that 50% is half the run time at 100%, not 50% output.... Meaning an IC20 and IC40 should function for #### amount of days ... but the IC40 could produce double the FC that the IC20 could in the same amount of time. Thats what i posted earlier...

More than likely, the true life span is a combination of these possibilities ... amount of FC produced & # days exposed to water. I think that is an accurate statement, however, Pentair cant tell how you will be "treating" the cell, so they can't include that re: longevity.

I think you are looking for a solid "it will last this many days" And i don't think you can get that number given so many variables that will affect longevity.

Of course at this point we are probably destined for the Deep End

 

[Pool Clown]

Re: new SWG

You understand my question perfectly and I agree it's wandered into the deep end I'm afraid... sorry about that. I think manufacturers or independant testing could validate the assumed increase in lifespan via testing - this testing need not take 5 years results could be extrapolated if necessary. As for real world testing - perhaps a very large pool with multiple SWG's in parallel could be setup with some cells that are IC40 and some that are IC20 etc - then over time validation of the cell's performance could be recorded.

I understand your question as well. I'm just saying that i think you would be hard pressed to get that data with accuracy, given the broad environmental range of even a single pool throughout the year.

 

[JasonLion]

Re: new SWG

Cell lifetime is confirmed by lab testing to be essentially a fixed total amount of chlorine produced. The only major exceptions to that rule are in conditions well outside of how we recommend caring for your pool. What we don't have data for is how frequently other failures, ie connector meltdowns, broken internal wiring, housing failure, etc, end the life of the cell before it has reached it's cell plate coating lifetime. Casually, cell plating lifetime appears to be the clearly dominant factor, but I don't believe that anyone has collected the kind of data needed to confirm that hypothesis.

 

[swimcmp]

Re: new SWG

In my experience with cells around five to seven years regardless of whether they are oversized or sized to the pool go buy a new one and have it on hand so you are ready when the old cell dies

 

[UnderWaterVanya]

Re: new SWG

In my experience with cells around five to seven years regardless of whether they are oversized or sized to the pool go buy a new one and have it on hand so you are ready when the old cell dies

If this is true there is no reason to by oversized, but conventional wisdom seens to disagree.

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[jblizzle]

Re: new SWG

In my experience with cells around five to seven years regardless of whether they are oversized or sized to the pool go buy a new one and have it on hand so you are ready when the old cell dies

If this is true there is no reason to by oversized, but conventional wisdom seens to disagree.

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An oversized cell would still be a good idea if you did not want to potentially have to run your pump close to 24/7.

 

[bobodaclown]

Re: new SWG (SOLVED)

Most members here try to provide the most accurate information they have at their disposal. That being said you as the owner/consumer have the ultimate responsibility how you want to spend your monies.
I read the original posters question and his next post. He's going with the IC-40.
I'm amazed how threads get in the weeds.

 

[UnderWaterVanya]

Re: new SWG

In my experience with cells around five to seven years regardless of whether they are oversized or sized to the pool go buy a new one and have it on hand so you are ready when the old cell dies

If this is true there is no reason to by oversized, but conventional wisdom seens to disagree.

Sent via Tapatalk...

An oversized cell would still be a good idea if you did not want to potentially have to run your pump close to 24/7.

Whoops! That is quite true.

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