What's Wrong with My Plumbing? - Chlorinator seems to get air trapped...

thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
Problem
My pool loses chlorine over the span of 8-10 days. The pool builder doesn't know why. I have to bleed air out of my system ever 7 days to keep chlorine from getting too low. They think it may have something to do with the way the system is plumbed.

Steps Followed (reproducible)
  1. Filled the chlorinator with 9 new tabs
  2. Bled the system of air (turn pump on high; let the water spill over the top of the chlorinator; put the lid on the chlorinator)
  3. Left the system running (switching between pool and spa once each per day)
  4. Never turned the system off
  5. Checked the water every 2 days
Other Relevant Info
  • The reading of chlorine was strong for the first few days
  • The chlorinator dial is turned to fully open (level 5)
  • I did not change any filters; no returns or drains were exposed to air
  • I have a no-main-drain pool
  • My equipment pad is higher than the pool
  • I have a separate pump for my water features (fountain and bubbler; note that, according to the plumber, these take a minute or more to actually get water flow because the equipment pad is higher than the pool, and so water drains out when they are turned off).
Pictures
See attached. One thing that really confuses me is the way it's plumbed on the return side. The pool builder owner doesn't understand why it was done this way on my pool (but he's not a plumber), and he said two other pools he built recently (which also have a spa) were not plumbed exactly like this.

Questions
  • Why is there a pipe connecting the pool and spa return lines?
  • Is it bad that the equipment pad is higher than the pool? What other problems could result from this?
  • What are the other possible reasons could cause air to accumulate in the chlorinator?
  • Even though I don't have any "main drains," I do have suction around the sides of the pool. Should those have been separated from the skimmers when going into the pump?
  • When I open the lid to the chlorinator, the water drains entirely from the chlorinator (when the pump is on low). However, if I turn the pump to high, water fills up the chlorinator and spills out the top. Why, when running in low speed, wouldn't at least some of the water stay in the chlorinator?
 

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Texas Splash

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Some of your questions will probably spur-on more questions. :) Let's get this discussion going starting with the questions in order:
1. I suspect that pipe is so you have the ability to adjust flow between the pool & spa. Even though you have actuators, perhaps the manual valves give you an added ability to manipulate flow.
2. Pad higher? Not a huge deal. I've seen some pools with equipment 6ft or more higher. In some cases, a check valve may be need to keep water from emptying out of the suction line and save pump basket prime, but overall not a huge deal.
3. I don't use my chlorinator hardly ever, and honestly neither should you because of the potential for CYA to build too high from tabs. But when I did use my chlorinator, it always had an air gap in it. I don't think it ever stayed completely full of water. Maybe other members will have shared experience on that one. But seriously, don't rely on it too long. A stack of tabs will add a significant amount of CYA, and you don't need it too high.
4. Side suction? Do you mean those lower side-wall drains? Some pools have those instead of a floor drain. They can be plumbed various ways, depending on the installer. Ideally, they would be plumbed separately from the skimmer in case there was ever a problem.

Keep the comments coming and we'll try to help.
 
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thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
First, thanks for the response. Second, indeed, more questions. :) Don't have much time at the moment, but a few quick follow-up questions.

2. Pad higher? Not a huge deal. I've seen some pools with equipment 6ft or more higher. In some cases, a check valve may be need to keep water from emptying out of the suction line and save pump basket prime, but overall not a huge deal.
What is a check valve? How would I include one to keep water from emptying? It is terribly frustrating to turn on the water features and have to wait several minutes. Last time I did it, it took nearly 5 minutes to get water flow.
3. I don't use my chlorinator hardly ever, and honestly neither should you because of the potential for CYA to build too high from tabs. But when I did use my chlorinator, it always had an air gap in it. I don't think it ever stayed completely full of water. Maybe other members will have shared experience on that one. But seriously, don't rely on it too long. A stack of tabs will add a significant amount of CYA, and you don't need it too high.
How do you balance the chlorine in your pool? Do you add tabs to the skimmer or to a floater? Shock a certain amount every week? Something else?
4. Side suction? Do you mean those lower side-wall drains? Some pools have those instead of a floor drain. They can be plumbed various ways, depending on the installer. Ideally, they would be plumbed separately from the skimmer in case there was ever a problem.
Correct, the drains on the side-wall. They are not plumbed separately, from what I can tell.

Added a fifth question to the main section: When I open the lid to the chlorinator, the water drains entirely from the chlorinator (when the pump is on low). However, if I turn the pump to high, water fills up the chlorinator and spills out the top. Why, when running in low speed, wouldn't at least some of the water stay in the chlorinator?
 

setsailsoon

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Oct 25, 2015
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These chlorinators work by diverting a small stream of water just upstream inside the fitting. In some installations there isn't sufficient pressure to move enough water through the cylinder. There could be an obstruction but I think you've checked that. They used to make an extension kit that would take water further upstream to increase the flow. As Pat says I wouldn't get too concerned as this should only be used for vacations since the tablets are about 1/2 CYA and you will very quickly have waaaay to much in your water that prevents the chlorine from disinfecting unless you drain a LOT of water to lower it. Way better to do your chlorinating with liquid chlorine or SWG.

I hope this helps.

Chris
 

Jimrahbe

Mod Squad
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Jul 7, 2014
15,866
Bedford, TX
P,

  • Why is there a pipe connecting the pool and spa return lines? This is called a make up system and it allows you to turn your spa spillover on or off or adjust the flow. You really only need this if you do not have automation
  • Is it bad that the equipment pad is higher than the pool? What other problems could result from this? Almost all equipment pads are at least a little higher than the pool
  • What are the other possible reasons could cause air to accumulate in the chlorinator? You are just running your pump too slowly.. Just another reason to not use tabs. It is not desinged for low flow.
  • Even though I don't have any "main drains," I do have suction around the sides of the pool. Should those have been separated from the skimmers when going into the pump? I suspect you wall inputs are for your other pump..
  • When I open the lid to the chlorinator, the water drains entirely from the chlorinator (when the pump is on low). However, if I turn the pump to high, water fills up the chlorinator and spills out the top. Why, when running in low speed, wouldn't at least some of the water stay in the chlorinator? Same answer as question 3.. Tab feeders are not designed for low flow pumps.
Thanks,

Jim R.
 
Last edited:

setsailsoon

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Oct 25, 2015
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Please do read click on the link in Marty's post. Number one is what we do. It's simple and highly effective. I have not changed my water since I took over from the pool service company 4 years ago. My pool has looked fantastic all the time for less than $10 per month. I Highly recommend you give it a try!

As you can see we also have experts here that can help with anything pool and pool equipment. They are all here to help ordinary pool owners take care of their pools. All volunteers, with only one focus to help you.

Good luck with the chlorinator and your pool!

Chris
 

thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
First off, thanks to all of you for the quick responses and advice!

These chlorinators work by diverting a small stream of water just upstream inside the fitting. In some installations there isn't sufficient pressure to move enough water through the cylinder. There could be an obstruction but I think you've checked that. They used to make an extension kit that would take water further upstream to increase the flow. As Pat says I wouldn't get too concerned as this should only be used for vacations since the tablets are about 1/2 CYA and you will very quickly have waaaay to much in your water that prevents the chlorine from disinfecting unless you drain a LOT of water to lower it. Way better to do your chlorinating with liquid chlorine or SWG.
I wish this were more commonly stated/communicated by the industry in general, but then again, I guess companies selling all the various products would lose money. :( Is it too much chlorine, or too much CYA, that would get into the pool from the tabs?
Regarding SWG, I was originally considering it, but I've read so many mixed reviews, articles, etc, that I really don't know what to believe and not to believe. I'll poke around the forums to see if I can find some better information.

  • Why is there a pipe connecting the pool and spa return lines? This is called a make up system and it allows you to turn your spa spillover on or off or adjust the flow. You really only need this if you do not have automation
  • Is it bad that the equipment pad is higher than the pool? What other problems could result from this? Almost all equipment pads are at least a little higher than the pool
  • What are the other possible reasons could cause air to accumulate in the chlorinator? You are just running your pump too slowly.. Just another reason to not use tabs. It is not desinged for low flow.
  • Even though I don't have any "main drains," I do have suction around the sides of the pool. Should those have been separated from the skimmers when going into the pump? I suspect you wall inputs are for your other pump..
  • When I open the lid to the chlorinator, the water drains entirely from the chlorinator (when the pump is on low). However, if I turn the pump to high, water fills up the chlorinator and spills out the top. Why, when running in low speed, wouldn't at least some of the water stay in the chlorinator? Same answer as question 3.. Tab feeders are not designed for low flow pumps.
All very helpful info. Regarding the first bullet and the "makeup system," can you explain how that works (or is there a good source for reading up on it)? I've been trying to think my way through this. If the horizontal pipe were not there, water could go to the pool, or the spa, but not both at the same time. The valve on the suction side is what dictates whether or not he spillway is "on" in that it sucks water from the spa (keeping the spillway off), or sucks water from the pool (effectively putting pool water into the spa returns and the spill being on), correct? Now, if we insert that horizontal pipe, the check valve would keep spa water from going back to the pool (?), but pool water could theoretically get to the spa(?) ?? I can't reason my way through the function this pipe/check valve/manual valve provide.

Chlorinating your pool.
You have a check valve on the suction side of the one pump you took pictures of.
I do remember reading this, now, when I was first getting ready to start up my pool, but I guess it didn't sink in. Thanks for the reminder.
For the check valve on the suction side--is that what should keep air from getting into my system/keeping water from draining? If so, I have one on the water feature suction side as well (see new pic), but that doesn't seem to keep water from draining. I'm assuming the direction of the flow matters, correct? Seems like the flow direction is correct. Is it possible that it's malfunctioning?

Please do read click on the link in Marty's post. Number one is what we do. It's simple and highly effective. I have not changed my water since I took over from the pool service company 4 years ago. My pool has looked fantastic all the time for less than $10 per month. I Highly recommend you give it a try!
As you can see we also have experts here that can help with anything pool and pool equipment. They are all here to help ordinary pool owners take care of their pools. All volunteers, with only one focus to help you.
Good luck with the chlorinator and your pool!
I guess I'm glad that I've had problems at this point; otherwise, I may not have learned all this until it was too late. :eek:

I've tried looking through the content on the forum and haven't found quite what I'm looking for, so I have several questions regarding liquid chlorine/bleach...
  • Where do you all buy your liquid chlorine from? Do you typically use liquid chlorine, or bleach?
  • How do I determine how much to add to my pool? Is there a chart that specifies how much to add per gallon of water in the pool to raise the chlorine 'x' amount?
  • Do you dilute it before adding it?
  • Do you pour it all around the perimeter, or in front of a return with the pump on, or does it matter?
  • How often do you find you need to add it?
  • Does it increase the pH overall? Having a spillway and water features, I understand that aeration increase pH, so I'm wondering if I'll need to add more acid consistently to keep the pH down.
 

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mknauss

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May 3, 2014
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Laughlin, NV
The check valves on the suction side should keep the suction line from draining. If they are not, then there may be debris in them keeping them from closing all the way.

The spa make up line is so that you can have your spillover and keep the spa water chlorinated all the time when in Pool Mode. But, with automation, it is not necessary. We suggest you close off that line and use your automation to run the spa in Spillover mode a couple times a day to keep your spa water chlorinated. That reduces the pH rise due to aeration.

Your bulleted questions (all are answered in Pool School)
  • Where do you all buy your liquid chlorine from? Do you typically use liquid chlorine, or bleach?
    • Liquid chlorine and bleach are the same. Most bleach is 6%. Many now have additives and you do not want that. Liquid chlorine can be purchased at Walmart, Home Depot, Lowes, and many pool stores.
  • How do I determine how much to add to my pool? Is there a chart that specifies how much to add per gallon of water in the pool to raise the chlorine 'x' amount?
    • You do your own FC testing then use that data in PoolMath to determine how much is needed to reach your FC target level based on your CYA. See FC/CYA
  • Do you dilute it before adding it?
    • No.
  • Do you pour it all around the perimeter, or in front of a return with the pump on, or does it matter?
    • Pour slowly at return with the pump running.
  • How often do you find you need to add it?
    • Daily
  • Does it increase the pH overall? Having a spillway and water features, I understand that aeration increase pH, so I'm wondering if I'll need to add more acid consistently to keep the pH down.
    • At the time it is added, the pH may rise a tiny bit. But as it is consumed the pH drops. So it is pH neutral.
 
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Jimrahbe

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P,

To add to what Marty said... The Make up line is really there for when you have no automation with a Spillover function.

Without automation, to keep your spa water fresh and chlorinated, you would have to manually move the valves from the pool mode to the spa mode each day.. What a pain that would be.. With the Make up line, even in the Pool mode, some water can be sent to the spa.. How much depends on the make up valve position. The check valve in that line just prevents the spa from draining back through that line when the pump is off. Plumbers will often put the line in whether you have automation or not.

In your initial pic the Make up valve is off and just how I would leave it.. If you don't have it already, I'd schedule the Spillover function to run twice a day for 30 minutes each time, to keep your spa water fresh.

Jim R.
 
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setsailsoon

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The check valves on the suction side should keep the suction line from draining. If they are not, then there may be debris in them keeping them from closing all the way.

The spa make up line is so that you can have your spillover and keep the spa water chlorinated all the time when in Pool Mode. But, with automation, it is not necessary. We suggest you close off that line and use your automation to run the spa in Spillover mode a couple times a day to keep your spa water chlorinated. That reduces the pH rise due to aeration.

Your bulleted questions (all are answered in Pool School)
  • Where do you all buy your liquid chlorine from? Do you typically use liquid chlorine, or bleach?
    • Liquid chlorine and bleach are the same. Most bleach is 6%. Many now have additives and you do not want that. Liquid chlorine can be purchased at Walmart, Home Depot, Lowes, and many pool stores.
  • How do I determine how much to add to my pool? Is there a chart that specifies how much to add per gallon of water in the pool to raise the chlorine 'x' amount?
    • You do your own FC testing then use that data in PoolMath to determine how much is needed to reach your FC target level based on your CYA. See FC/CYA
  • Do you dilute it before adding it?
    • No
  • Do you pour it all around the perimeter, or in front of a return with the pump on, or does it matter?
    • Pour slowly at return with the pump running.
  • How often do you find you need to add it?
    • Daily
  • Does it increase the pH overall? Having a spillway and water features, I understand that aeration increase pH, so I'm wondering if I'll need to add more acid consistently to keep the pH down.
    • At the time it is added, the pH may rise a tiny bit. But as it is consumed the pH drops. So it is pH neutral.
Marty has helped many, many people get control of their pools. He's very good at this. Just follow his advice and you'll be in control of a spectacular pool with not much effort and very little $. The only thing I'd add is to be sure you buy pure bleach with no fragrances or additives. Most Clorox brand now has additives so it won't be one you'd want to uses. In most cities there are a couple of places that sell refillable 2.5 gal jugs of 10-12%. This usually the best price and more convenient. Also, SWG have come a long way in the last five years. Anode catalysts have improved tremendously so they last longer and require less salt in the water. We waited 'till we had a lot of friends and people here raving about SWG. Switched 2 months ago and we the improved feel of the water. My wife says it's like going to a Spa!

Good luck with your pool!

Chris
 

thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
The check valves on the suction side should keep the suction line from draining. If they are not, then there may be debris in them keeping them from closing all the way.
Would the best way to do this be to take the screws out and the top off and look for debris? I'm sure that sounds like a stupid question, but this is my first experience with a pool, and with plumbing, so I don't want to mess anything up.

The spa make up line is so that you can have your spillover and keep the spa water chlorinated all the time when in Pool Mode. But, with automation, it is not necessary. We suggest you close off that line and use your automation to run the spa in Spillover mode a couple times a day to keep your spa water chlorinated. That reduces the pH rise due to aeration.
In your initial pic the Make up valve is off and just how I would leave it.. If you don't have it already, I'd schedule the Spillover function to run twice a day for 30 minutes each time, to keep your spa water fresh.
Gotcha. I'll keep that line closed off. I do have automation running on a schedule, where the spillover is running 4 hours a day (high speed on my pump). Sounds like I could decrease that time, and just run the pool only at high speed for 4-6 hours instead?

Your bulleted questions (all are answered in Pool School)
Sorry I missed the info. Thank you for the info inline!

How do I determine how much to add to my pool? Is there a chart that specifies how much to add per gallon of water in the pool to raise the chlorine 'x' amount?
  • You do your own FC testing then use that data in PoolMath to determine how much is needed to reach your FC target level based on your CYA. See FC/CYA
I didn't notice the section at the bottom that allows me to specify the amount and type of bleach and produce an impact. I'll try this tool out soon!

  • How often do you find you need to add it?
    • Daily
Wow, I didn't realize this. Does this mean you test your water every day? Or does the required amount not change significantly from day to day if no one is in the water and weather patterns aren't changing? I test my water every few days, but I can start checking every day. Do you do it at the same time of day? If these are answered in Pool School, just ignore these questions--I plan to read it in detail tonight.

Marty has helped many, many people get control of their pools. He's very good at this. Just follow his advice and you'll be in control of a spectacular pool with not much effort and very little $. The only thing I'd add is to be sure you buy pure bleach with no fragrances or additives. Most Clorox brand now has additives so it won't be one you'd want to uses. In most cities there are a couple of places that sell refillable 2.5 gal jugs of 10-12%. This usually the best price and more convenient.
Good advice. I'll check around and see what resources I have around me. I was surprised to not see something front and center on Amazon (where I do most of my shopping)--most of what they have is not pure liquid chlorine.

Also, SWG have come a long way in the last five years. Anode catalysts have improved tremendously so they last longer and require less salt in the water. We waited 'till we had a lot of friends and people here raving about SWG. Switched 2 months ago and we the improved feel of the water. My wife says it's like going to a Spa!
  • Which SWG did you put in? Was it difficult to convert (conceptually, I would think not)?
  • I'll be curious to know if you notice any impact to materials. What material do you have for coping? Did you have any concerns with eroding equipment, materials, etc, over time?
  • What convinced you to switch?
Thanks, again, everyone!
 

mknauss

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May 3, 2014
23,659
Laughlin, NV
There is no reason to run your pump on high at all. Other than if needed to dissolve the trichlor tablets which you should discontinue using on a daily basis.

Try lowering your pump rate in 500 rpm increments (lowest i would suggest going is 1200 rpm) until you see an impact on skimming.

As far as testing, we recommend you test FC and pH every day until your learn your pool water characteristics. Then most people get to the point of adding the same amount of liquid chlorine every day and testing a few times a week. Many can just look at their water and see that the water needs testing as it does not look right.

A SWCG generates chlorine for you and adds what you tell it every day.
 

setsailsoon

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Oct 25, 2015
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I went with Circupool RJ30+. Based this on price, warranty, and reviews I trust. Install was easy peasy. No concerns about corrosion or deposits. CSI is always good w TFP method. I got tired of jug lugging and I was pretty sure my wife would love the feel of it. I think it may pay out in reduced Spa visits!

Chris
 

thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
There is no reason to run your pump on high at all. Other than if needed to dissolve the trichlor tablets which you should discontinue using on a daily basis.
Try lowering your pump rate in 500 rpm increments (lowest i would suggest going is 1200 rpm) until you see an impact on skimming.
First, glad to know I don't need it on high. Yes, I was primarily putting it on high to pump chlorine around.

Now, your comment on skimming is interesting. Either I had WAY to high of expectations of what the skimmer was going to do/take care of from the surface of the pool, or it's not working correctly (not enough suction?). What should my expectation be of a skimmer? The surface of my pool is never perfectly clean (not expected), nor is it mostly clean (expected). At any given time, there are bugs or other debris sitting on the surface. When I go to empty the skimmer basket, I do see a few bugs there, but not many. It doesn't seem to catch much other than leaves. Perhaps this is normal, though?

As far as testing, we recommend you test FC and pH every day until your learn your pool water characteristics. Then most people get to the point of adding the same amount of liquid chlorine every day and testing a few times a week. Many can just look at their water and see that the water needs testing as it does not look right.
Whew. I figured (rather, hoped) this would be the case. I feel like I'm a long ways off from that, but I look forward to getting there some day. ;)

I went with Circupool RJ30+. Based this on price, warranty, and reviews I trust. Install was easy peasy. No concerns about corrosion or deposits. CSI is always good w TFP method. I got tired of jug lugging and I was pretty sure my wife would love the feel of it. I think it may pay out in reduced Spa visits!
The OP has a Pentair EasyTouch8 automation system. A Pentair Intellichlor system would plug into that automation and be fully automated.
I would probably go with Pentair for the ease of automation, but I certainly was curious. I haven't felt the water from a SWG, but assuming it's something like what is produced by my water softener, I have no doubt I would prefer that. My primary concerns (and the reason I didn't go with one at the outset) are (1) wear on the coping (flagstone); (2) wear on the parts within the system (corrosion on seals, light fixtures, etc); and (3) potential problems with generator/automation itself.
 

setsailsoon

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I would probably go with Pentair for the ease of automation, but I certainly was curious. I haven't felt the water from a SWG, but assuming it's something like what is produced by my water softener, I have no doubt I would prefer that. My primary concerns (and the reason I didn't go with one at the outset) are (1) wear on the coping (flagstone); (2) wear on the parts within the system (corrosion on seals, light fixtures, etc); and (3) potential problems with generator/automation itself.
I have a Jandy system including their automation which I really, really like. Only problem for me is that I DIY all I can and buy mostly online both of these cause Jandy to reduce their warranty to zero. Others like your brand may reduce the warranty but at least you get some warranty. In my case Jandy chlorine output was considerably lower and more expensive. So I hooked mine up to a spare relay in the automation. That way I can tweak run-time with the wifi app and I have to walk out to the controller when I need to increase % power. You have this option also but if I had the pentair I may well have gone for the full automation.
 

mknauss

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Laughlin, NV
Your expectation is probably a bit too high on the skimmer. Larger stuff gets there more often than small stuff.

Biggest factor is where the skimmer is versus prevailing wind direction. If you are fighting the wind, they do not work well.
 

Jimrahbe

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P,

Even well operating skimmers will not reach out into the middle of the pool and pull debries into them... They only work if the debris happen to float near enough to the skimmer's mouth. The key, in my mind, is patience.. If I sit and watch a leaf on top of the pool water, it will eventually pass close enough to the skimmer to get sucked in. You have to have operating Weir doors just behind the skimmer's mouth.. If this is a new pool, I'm sure they are there... If this is an old pool, there is only a 50/50 chance that they are still there. Water level is also important. Too high or too low will cut down the the skimmer's efficiency.. The water level should be halfway up the mouth of the skimmer. You do not need a toilet like swirl to make the skimmers work. I run my pump at only 1200 RPM and yet I find plenty of debries in my skimmer baskets when I clean them. If it floats my skimmers collect it, if it falls to the pool floor, my robot pics it up. Works well for me.

Thanks,

Jim R.
 

thephatp

Well-known member
Jul 8, 2018
53
Austin, TX
Your expectation is probably a bit too high on the skimmer. Larger stuff gets there more often than small stuff.
Biggest factor is where the skimmer is versus prevailing wind direction. If you are fighting the wind, they do not work well.
The placement probably isn't terrible, but it's not great, either, IMHO. My pool is freeform, but generally rectangular overall. The wind blows across the length of the pool (both directions) a vast majority of the time. Both skimmers are the longer walls, meaning the wind blows past them rather than into them. I'm guessing that is good, so that more can be picked up as the wind blows debris in front. However, I have to nook areas where debris gets trapped, and it doesn't move around after that.

Even well operating skimmers will not reach out into the middle of the pool and pull debries into them... They only work if the debris happen to float near enough to the skimmer's mouth. The key, in my mind, is patience.. If I sit and watch a leaf on top of the pool water, it will eventually pass close enough to the skimmer to get sucked in. You have to have operating Weir doors just behind the skimmer's mouth.. If this is a new pool, I'm sure they are there... If this is an old pool, there is only a 50/50 chance that they are still there.
This is a new build (Nov 2018), but no Weir doors. :/ I guess I could add some. I run my pumps 24 hours a day, so they are never off; just on low most of the time. (Is this bad, or unnecessary?)

Water level is also important. Too high or too low will cut down the the skimmer's efficiency.. The water level should be halfway up the mouth of the skimmer. You do not need a toilet like swirl to make the skimmers work. I run my pump at only 1200 RPM and yet I find plenty of debries in my skimmer baskets when I clean them. If it floats my skimmers collect it, if it falls to the pool floor, my robot pics it up. Works well for me.
I think my low setting is 1200 or 1150. My high setting is 3450 (which is running about 4 hours a day). The water level, to keep it in the middle of the skimmer opening, means its about 3/4 down the tile. I'd prefer to keep the water closer to 1/2 down the tile, but it was too close to the top of the front of the skimmer at that level.