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Thread: My MD will not seal...

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    My MD will not seal...

    Hello everyone, first time poster here. I closed down the pool yestreday and things went ok. I blew out all the lines and filled the skimmer lines with antifreeze, as well as the pump. I have two main questions.

    1. ON one of the skimmer lines, the antifreeze comes almost all the way back up into the skimmer, so the line is completely filled, on the other one, I would say that the lineis only about half way filled with anti freeze, with a gizmo on the top of that line also. Will both lines be ok if I leave them this way?

    2. Here is my biggest concern. After I blew out the MD, and closed off the ball valve to it. I could hear air leaking back out of it. So since the air is leaking out, the water is leaking in! Is there something I can do to get the MD line not to freeze? we live in KC and it will get down to 0 in the dead of winter here. So I am not sure if the line will be below the frost line or not.

    Thanks in advance for your help,

    Jeffrey
    10,000 gallon
    Viking Freeform Fiberglass Inground Pool. FNS Plus DE Filter Pentair Challenger .75hp pump

    NC KANSAS44

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    Join Date
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    Coastalish 'down easter'
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    Re: My MD will not seal...

    Jeffery, welcome to TFP!!

    I'd say that the valve for the skimmer that has it 'full' was closed when you added the antifreeze and it's 'vapor locked' looking full. No problem (you'll be going out to play with the valves to solve the MD issue ), remove both Gizzmos and open the valves for the skimmers, this will let the antifreeze find the lowest part of the pipe and properly mix with any water still in there to protect the lines - be sure to retape the Gizzmos when you reinstall them!

    For your MD issue, you want to take care of the skimmer lines first and then close the valves to the skimmers. Then reblow the MD, close the valve and use an expandable rubber plug (with the wingnut to tighten it) to stop the air/ water from evacuating/ reentering the line

    If you have further questions on this, or any other pool matter, simply ask and we'll be more than happy to aid you!
    Luv& Luk
    -Ted

    Having done construction and service for 4 pool companies in 4 states starting in 1988, what I know about pools could fill a couple of books - what I don't know could fill a couple of libraries :-D

    POOL SCHOOL, TF Testkits, Jason's Pool Calculator, CYA vs. cl chart, (Just a few DARNED handy links!)

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    Re: My MD will not seal...

    Thanks so much for the tips! I will check back and let you know how it goes. I got the supplies from the local pool store after I read your post.

    Jeffrey
    10,000 gallon
    Viking Freeform Fiberglass Inground Pool. FNS Plus DE Filter Pentair Challenger .75hp pump

    NC KANSAS44

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    Re: My MD will not seal...

    Sometimes the valves themselves can leak air from the stem of the handle, in this situation we put a union before the valve and plug the union with a rubber plug.
    -Kevin
    X-Pert Pool Service
    x-pertpool.com
    X-Pert Pool on Facebook and @XPertPoolServic on Twitter
    22,000 gal / 16' x 32' / Vinyl / Hayward s244t /Pentair SuperFlo 1 hp

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    Re: My MD will not seal...

    OK, I did it again...this time hopefully right! I did notice when I blew out the skimmer lines, that there was still some water in the pipes. Since I was blowing from the pump to the skimmer, I could not get ALL of the water to come out vertically . I also stuck the shop vac down in the lines and sucked out some more of the water, but I could not get it all. I added a gallon of antifreeze to each line....will that amount mix with the water in the pipes and still prevent freezing? Also, i wrapped the gizmo 3 times with tape, and still noticed bubbles coming up into the skimmer around the gizmo when I was done blowing out the MD and put the rubber cap on the end, I also filled the skimmers most of the way with antifreeze. Are the bubbles going to cause a problem?

    Thanks again for te help, Jeffrey
    10,000 gallon
    Viking Freeform Fiberglass Inground Pool. FNS Plus DE Filter Pentair Challenger .75hp pump

    NC KANSAS44

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    Join Date
    Mar 2007
    Location
    Coastalish 'down easter'
    Posts
    4,160

    Re: My MD will not seal...

    You simply can't avoid having some water in the lines The water clings to the sides of the pipe.

    What you can do, in the future, is to apply the air for 10 seconds and then stop for ~5 sec. to let the water puddle at it's lowest point(s) and then blow again, repeat this a few times and you won't have enough water in the line to make an icecube :P Then add a gallon of antifreeze to mix with the little water still in the line and call it good

    If your skimmer lines run below the frostline, you are safe with what you've done!

    Now let's talk about the Gizzmos bubbling. I don't like to apply air to an already plugged line! (this should be discussed in the "201" section) There is 'positive pressure' on a plug and 'negative pressure' - the former is caused by the force of the water against the plug from the pool, and the o-ring or Teflon tape will hold against that - the negative pressure is the opposite, it's caused by your blower working against the seal and may be strong enough to defeat the seal, causing bubbles. However, I believe that, if you close the valve where you're blowing from, that the pressure will equalize and the 'positive' seal will hold

    Others may have more info on this, but I think you'll be fine for the winter
    Luv& Luk
    -Ted

    Having done construction and service for 4 pool companies in 4 states starting in 1988, what I know about pools could fill a couple of books - what I don't know could fill a couple of libraries :-D

    POOL SCHOOL, TF Testkits, Jason's Pool Calculator, CYA vs. cl chart, (Just a few DARNED handy links!)

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