Extra clean (UV?) pools in the Boston, MA area

[n240sxguy]

A swg can be added at any time. The pump doesn't have to be replaced. I run my pump 12 hours a day on low mostly so I can see the water move and keep the surface skimmed. Depending on how long she runs her current pump, you may be able to put the swg in now and not have to change anything with the pump. The pump change was mainly to allow 24/7 filtration for your specific situation without costing a fortune in electricity. With a swg you have two parameters you can adjust to make chlorine; pump run time and swg output percentage. The swg will either be on or off. The output percentage lets you select how long it is on. 12 hours at 50% will make the same chlorine as 6 hours at 100%. It just turns the cell on and off every so often if you have it set at less than 100%. If you get to a point where you've got the swg at 100%, and it's still not making enough chlorine for your pool, then you have to up your pump run time so the swg can be on longer. On a smaller swg you would have the output at 100%, be running 24/7, and still not be making enough chlorine. I think that's where the 24/7 and swg part came from.

 

[Swampwoman]

^ in this case, the article about the two part polymer floc was indeed referring to PRS. Originally, Id been referring to something I read recently but can't find that suggests Alum floc, where you vac to waste, is also supposed to work for crypto removal.

An SWG doesn't require a new or special pump, BUT the run time required to produce adequate FC can affect electrical bills and your friend's pool is larger at 35,000 gallons.

Do you know what brand and rated HP her current pump is? Sometimes its possible to change out a motor for variable speed instead of replacing the entire pump (eg the wet end of the pump where the basket is.)

I am doing a motor upgrade today actually - the variable speed motor was $400 at Inyopools - its a 1.65 Century (AO Smith) that fits a Maxflo (Hayward) pump. The install should be about an hour and a half, according to the installers I hired from a local pool service co. Even running the heater, which requires a much higher flow, I should still be able to save 50% or more on my electric

I'm just letting you know in case you're looking at budget line items to reduce, though there's no reason not to go with a nice Intellifo with its easy automation integration.

If you itemize deductions on your tax returns, you will be able to write off equipment and labor on this project as a medical expense I believe, particularly if your healthcare team advocates hydrotherapy for your daughter. If you have easy access to an accountant who knows your circumstances, you might want to pre-check how these deductions work and what the net impact will be for you tax wise. As you're likely aware, med expenses have to be higher than 10% of your income before the itemized deduction have much impact, but its worth keeping in mind.

In my area, I don't seem to have any difficulty finding pool co labor to install equipment that I research and buy from vendors like Inyo. I download the equipment PDFs and send to them before the call. But I book the service AFTER I purchase the equipment and just say "I have a source for discounted but new equipment I like, would you be willing to install "x-brand & spec" or "Is your company an installer for x-brand of heater/swg/pump etc."

I've never been refused They want the labor. You will just be later in their priority list because the value of your job is less for them. But in the case of my heater, I saved more than 50% this way, same with my swg.

This works best if you inform yourself on installation a bit (mfgs always have manuals) so that you're vetting the work a bit, and also using a company that deals in the brand. Eg I used a different company with my swg than my heater based on which were authorized installers of respective brands.

Hope those tips help you work up a plan!

 

[dfmk]

I can’t stop being amazed at the depth of information I am getting from this forum and the willingness of folks to help. Can’t thank you guys enough.

N240sxguy, your explanation of how SWG run time interacts with pump run time helps, but I am still a little bit confused regarding one aspect of it: would you ever want your SWG to be on if the pump is not running? At first from your description I thought that the pump and the SWG need to be in sync, so that when the SWG turns on (assuming it is not set to 100%), the pump will send water through it. But then it seemed that you could turn them on and off independently. What is the use in SWG producing chlorine if there is no flow through the unit to push it out into the pool? I am probably misunderstanding something.

Also, since some said that for a pool this large even the largest SWG units are on the edge of too small, I am wondering what would one do if you run the SWG at 100% and the pump runs 24/7, but then you go to measure FC and there is still not enough? Would you just dump some bleach into the pool at that point? And then if it turns into a pattern and you realize that SWG is simply not keeping up, would you install a chlorine injector in addition to the SWG unit?

Swampwoman, thank you for the tips on dealing with contractors. Now that I have the equipment is more or less figured out, dealing with the contractors is my next big unknown (specifically, how to find the right ones, someone who won’t screw up the installation and make the pool unsafe to use in the process), so your input is very, very helpful.

THANK YOU!

 

[kimkats]

You do NOT want the swg to be on without the pump running.

We had someone just call us this "KWA" Knowledge Without Attitude" I think that fits us purrfect!



Kim

 

[n240sxguy]

With any luck the swg you install will be able to keep up. If you get one of the small ones, then you would have to supplement somehow. No, a swg NEVER needs to be allowed to run without water flow. In a worst case scenario it can make a bomb. That's why they all come with flow switches as a safety precaution. You don't want to rely only on those, that's why it needs to be wires to that it can only come on when the pump is running. If the pump lost prime or something and wasn't really pumping water, the flow switch would be a safety backup to keep the swg from powering on.

 

[dfmk]

You do NOT want the swg to be on without the pump running.

No, a swg NEVER needs to be allowed to run without water flow.

That makes sense. So here is where I got confised. From n240sxguy's explanation I understood that an SWG set to 50% simply turns itself on and off to run 50% of the time. So if I want my pump to only run 50% of the time as well, how do you get them to talk to each other so that they are on at the same time? Would you need some kind of a controller at that point that will orchestrate their actions?

 

[n240sxguy]

Most swg's are on, I believe, a two hour repeating time schedule. Let's assume your swg is tied to your pump timer, as it should be. If you run your pump for 6 hours, and have your swg on 50%, the swg should be on for one hour, and off for one hour, repeating until the time is up. So, your pump ran for 6 hours, and your swg ran for an hour every other hour. It ran for a total of three hours during your pump's six hour run time. If you go to 75%, it will run for 90 minutes, and be off for 30 minutes repeating until the pump shuts off. 100% and it just stays on the whole time. Once the swg gets power it just starts its own cycle until power is taken away from it.

 

[dfmk]

Got it. I think I understand now. So the problem really comes down to finding that optimal combination of settings that will provide the right amount of chlorine, through trial and error -- messing with the settings followed by testing the water. Right? The only bit that I still am struggling to understand is why would you ever run the SWG on anything less than 100% output. If I only wanted it to run for an hour every other hour, like in your example, why wouldn't I set the timer for both the pump and the SWG to run on that schedule? What's the benefit in running the pump for all 6 hours if the SWG is on for only 50% of that time? Filtration?

 

[IsThisWhereIPutMyName?]

Yes - you generally need more pumping / filtration time than chlorine production time. So if you need to / want to keep the pump running 24 hours you need less % of that time to keep up with the chlorine loss.

 

[n240sxguy]

Got it. I think I understand now. So the problem really comes down to finding that optimal combination of settings that will provide the right amount of chlorine, through trial and error -- messing with the settings followed by testing the water. Right? The only bit that I still am struggling to understand is why would you ever run the SWG on anything less than 100% output. If I only wanted it to run for an hour every other hour, like in your example, why wouldn't I set the timer for both the pump and the SWG to run on that schedule? What's the benefit in running the pump for all 6 hours if the SWG is on for only 50% of that time? Filtration?

It all depends on your needs/wants. I want my water moving some during my waking hours so I have my pump set to run 9-9. As the weather gets warmer and the bather load increases, I turn the swg output up. As the temp and bather load decreases, I turn the output down. If you didn't care at all about anything other than chlorine production, you could leave the swg at 100%, and vary the pump run time. A couple hours a day at the beginning and end of the season, and 8-12 in the peak times. Since you're wanting to run the pump 24/7 to allow UV exposure, and maximum filtration for your daughter's health safety, you'll want to vary the swg output to match the chlorine production that is actually needed. If you have your cya at 70-80 and need 6-8fc, you'll basically overrun your swg in the beginning, and back it down to the point that it's output matches your usage and you maintain the number you are shooting for. If you are a little low, you raise it. If you are a little high, you cut it back. If you left it running 24/7, and it wasn't too small for your pool, your FC would just keep going up until it got to the point that it found some equilibrium point. You might want 6-8, but could end up in the 20's-30's. You would also reduce your swg cell life by doing that. They are only rated for so many hours of production before the rubidium coating on the titanium plates wears thin enough that the cell has to be replaced.

 

[dfmk]

Thank you n240sxguy, I couldn't ask for a more complete explanation. Only a few days ago I knew so little about pools that I didn't think I would ever be able to say this, but: I don't have any more questions for now. I guess the ball is entirely in my court now to act on all the information I now possess. Of course, I am fully in the hands of my friend who owns the actual pool, but at least I know enough to work with her on coming up with a plan of action that both minimizes the sacrifices she will need to make and brings her pool water quality to a level that would be safe enough for my daughter to use. As we progress along the steps I will have no choice but to rely on your guys help and hand holding. That's assuming that after I have sucked up so much of your time with this thread you are not sick and tired of answering my dumb questions. But for now I would like to THANK YOU THANK YOU THANK YOU ALL one more time for the outpouring of help and compassion that you have shown over the few days since I started this thread.

THANK YOU!

 

[JoyfulNoise]

I think it goes without saying that nothing would be more enjoyable for all of us to see your plans come to fruition and this thread end with a beautiful picture of you and your daughter splashing around in the pool!!

Just keep asking questions, we're happy to help!!

 

[n240sxguy]

Yeah, if you have any more questions, keep them in this thread so we don't miss them. Your friend may not know it yet, but she's getting a sweet deal. Once you get going with transforming her pool, you're going to put the way it is now to shame. I don't care how nice her water is now, it'll look like bathwater compared to mountain spring water when you're done.

 

[Swampwoman]

DFMK, please invite your friend to join us on the forum so that we can also help her have "trouble free" pool operation and so that we can help if she has questions or specific features of the pool that might influence the plan

And by way of update, I've now got my new motor configured in a way that the heaters happy for its run, the swg is happy, and my total scheduled 24 hrs is about a quarter of my previous single speed pump in terms of KWH (kilowatt hours).

 

[kimkats]

The smile I see in this post so makes my day!

Matt and guy are the rock stars here!!!!

Kim

Thank you n240sxguy, I couldn't ask for a more complete explanation. Only a few days ago I knew so little about pools that I didn't think I would ever be able to say this, but: I don't have any more questions for now. I guess the ball is entirely in my court now to act on all the information I now possess. Of course, I am fully in the hands of my friend who owns the actual pool, but at least I know enough to work with her on coming up with a plan of action that both minimizes the sacrifices she will need to make and brings her pool water quality to a level that would be safe enough for my daughter to use. As we progress along the steps I will have no choice but to rely on your guys help and hand holding. That's assuming that after I have sucked up so much of your time with this thread you are not sick and tired of answering my dumb questions. But for now I would like to THANK YOU THANK YOU THANK YOU ALL one more time for the outpouring of help and compassion that you have shown over the few days since I started this thread.

THANK YOU!

 

[dfmk]

I think it goes without saying that nothing would be more enjoyable for all of us to see your plans come to fruition and this thread end with a beautiful picture of you and your daughter splashing around in the pool!!

Just keep asking questions, we're happy to help!!

It's been four years since I last posted here, and every time I think about it I still get amazed with the outpouring of support that I found on this forum.

(For those who are reading this thread for the first time, to save you the work of scrolling through the previous posts, a summary: our daughter is a liver transplant recipient who takes high doses of immunosuppresive drugs. We would really like to teach her to swim, but natural bodies of water, as well as public pools, are not safe for her to use. So I was looking for advice on how to equip a friend's pool with the right gear to maximize its water safety.)

So this is where we finally ended up: the friend that I was originally talking to lost interest in the project, and I didn't want to push. But two years later another friend actually said he would allow me to install the additional purification equipment that my daughter needed. Last summer we made a few trips to his house (see photo attached, as promised) and my daughter loved everything about it and started learning to swim. However, in practice we are not spending nearly enough time at the pool for her to actually learn -- they live about 1.5hr drive away from us and have busy schedules which rarely lines up with ours. They are a very nice family that have been very kind and welcoming to us (starting with the fact that they agreed to the whole arrangement), so we don't want to impose ourselves on them with frequent visits. So we are looking for a plan B. Possibly it will entail buying a small summer house and building our own pool there. I will also post in the Coffee Bar forum to see if there are any pool owners in the Boston area who would be willing to rent their pool to us by the day, so that we can continue teaching our daughter to swim. Maybe they will even agree to us investing in their pools to equip them with the necessary sanitation equipment. We'll see where it goes.

But whatever happens -- I will forever be grateful to everyone who responded on this thread not only for the knowledge that you shared, but also the kindness with which it was done. Thank you everyone!