Can I create airlock for main drain this way

[EzriJax]

Howdy!

Here I am, closing my pool later than I should again. We had a rough season trying to find the leak, and then getting someone to fix it. I’ll post about that separately. Consequently I didn’t get my plumbing completely fixed-my main drain is plumbed directly to my pump and we ran all summer sans skimmers (which is awful btw unless you LOVE manually skimming your pool several times a day.)

Now, I’ve got the pool mostly closed, so that I could minimize risk while I work out how to deal with this main drain issue. I cleaned the pool as best I could (robot vacuum died mid-august, can’t use skimmers, and my $100 battery operated vacuum was left out in the rain in pieces by my child so I now have NO vacuum…) and balanced the water. Drained below returns, emptied skimmers with a hand pump, drained and removed plugs, gauge etc from filter, drained and removed basket from filter. I also disconnected the union right before the returns and blew some air in there with a small tire compressor. It kinda worked. It took a while, and I never got a big “blow” of air but eventually water was just trickling so I figured it’s good enough for now.

This weekend, I finally have my compressor back from my dad and I’m going to attempt to clear the returns completely and fill with antifreeze and create the airlock on the main drain BUT, I want to confirm my plan is reasonable. I’d love if someone can confirm it’ll actually work but I’m thinking what I’m going to do is not a common or recommended practice so maybe no one knows.

Last year I hacked my busted valve off and used my shop vac to push as much air in as I could and then jammed a rubber plug in the pipe. I know that water rushed back in in the time it took me to get the plug in place and I took a chance with my pipes by doing that. Well, this year I don’t have a shop vac (my mom stole it-long story) and my pipe is not open for me to do it that way. So, my plan is to create the airlock in the pump itself.

I have a ball valve that will fit into the drain plug port that will accept my air compressor so what I plan to do is use a rubber plug to block off the opening to the impeller, then I’ll Teflon tape and reinstall the second drain plug, give a fresh coat of lube to the lid, tighten it down, and then blow air into the basket drain fitted with the ball valve till I see bubbles, then close the ball valve and disconnect the compressor.

My concern is if the pump lid will hold the airlock all winter? Or, at all? I have an extra lid…should I use that one in case there will be strain on it?

Is there anything else wrong with my plan? Any other suggestions? I’m on a tight budget and don’t have anyone to help me so I’m on my own out there, with limited resources.

Here’s a picture of the pump set up right now:

 

[Bperry]

Howdy!

Here I am, closing my pool later than I should again. We had a rough season trying to find the leak, and then getting someone to fix it. I’ll post about that separately. Consequently I didn’t get my plumbing completely fixed-my main drain is plumbed directly to my pump and we ran all summer sans skimmers (which is awful btw unless you LOVE manually skimming your pool several times a day.)

Now, I’ve got the pool mostly closed, so that I could minimize risk while I work out how to deal with this main drain issue. I cleaned the pool as best I could (robot vacuum died mid-august, can’t use skimmers, and my $100 battery operated vacuum was left out in the rain in pieces by my child so I now have NO vacuum…) and balanced the water. Drained below returns, emptied skimmers with a hand pump, drained and removed plugs, gauge etc from filter, drained and removed basket from filter. I also disconnected the union right before the returns and blew some air in there with a small tire compressor. It kinda worked. It took a while, and I never got a big “blow” of air but eventually water was just trickling so I figured it’s good enough for now.

This weekend, I finally have my compressor back from my dad and I’m going to attempt to clear the returns completely and fill with antifreeze and create the airlock on the main drain BUT, I want to confirm my plan is reasonable. I’d love if someone can confirm it’ll actually work but I’m thinking what I’m going to do is not a common or recommended practice so maybe no one knows.

Last year I hacked my busted valve off and used my shop vac to push as much air in as I could and then jammed a rubber plug in the pipe. I know that water rushed back in in the time it took me to get the plug in place and I took a chance with my pipes by doing that. Well, this year I don’t have a shop vac (my mom stole it-long story) and my pipe is not open for me to do it that way. So, my plan is to create the airlock in the pump itself.

I have a ball valve that will fit into the drain plug port that will accept my air compressor so what I plan to do is use a rubber plug to block off the opening to the impeller, then I’ll Teflon tape and reinstall the second drain plug, give a fresh coat of lube to the lid, tighten it down, and then blow air into the basket drain fitted with the ball valve till I see bubbles, then close the ball valve and disconnect the compressor.

My concern is if the pump lid will hold the airlock all winter? Or, at all? I have an extra lid…should I use that one in case there will be strain on it?

Is there anything else wrong with my plan? Any other suggestions? I’m on a tight budget and don’t have anyone to help me so I’m on my own out there, with limited resources.

Here’s a picture of the pump set up right now:View attachment 542061View attachment 542061

Does your compressor have enough air volume to get bubbles coming out of the main drain? If so I’d think you have a decent shot at it. It lots of times air compressors aren’t able to create the volume of air needed for that.

If you’re stuck with the compressor as your only option, you can get the biggest tank you can find and open up your ball valve to let as much air get in as fast as possible and then shut the valve. Hopefully enough air will get in and push whatever water is in the pipe below the frost line.

I assume you’ve plugged the returns at the pool wall so water can’t get in when it rains/snows?

 

[EzriJax]

I have no idea if it has enough volume. I really don’t know much about it at all. I got it as a birthday gift, and haven’t used it at all. I’ve watched several videos about closing pools with compressors but they either use a tankless variety (mine has a tank) or they say “be careful not to use too much pressure” which I understand but what is too much?

I have the ability to regulate the pressure. I also read a post here that says to start blowing the lines as soon as you turn the compressor on so it blows air thru the lines instead of filling the tank.

I was thinking I’d do that-run the compressor at start up thru the return lines to finish those off-then let it build a little pressure to blast the main drain?

How much is too much? I have flexible 1.5” piping if that’s useful info. The main drain is about 10-12’ away from pump, and it’s over 8’ deep. Pump/equipment is about 1.5’ higher than water level, when it’s full. I don’t know what’s relevant, so that’s as much as I know, in case it matters.

I’m very grateful for help.

 

[Bperry]

I have no idea if it has enough volume. I really don’t know much about it at all. I got it as a birthday gift, and haven’t used it at all. I’ve watched several videos about closing pools with compressors but they either use a tankless variety (mine has a tank) or they say “be careful not to use too much pressure” which I understand but what is too much?

I have the ability to regulate the pressure. I also read a post here that says to start blowing the lines as soon as you turn the compressor on so it blows air thru the lines instead of filling the tank.

I was thinking I’d do that-run the compressor at start up thru the return lines to finish those off-then let it build a little pressure to blast the main drain?

How much is too much? I have flexible 1.5” piping if that’s useful info. The main drain is about 10-12’ away from pump, and it’s over 8’ deep. Pump/equipment is about 1.5’ higher than water level, when it’s full. I don’t know what’s relevant, so that’s as much as I know, in case it matters.

I’m very grateful for help.

You don’t want much pressure. I wouldn’t let it get above 25psi. How large is the air tank?

I’m skeptical the compressor will work with 8’ deep water but if that’s your only option it is what it is. I’d for sure fill the air tank but limit it to ~20psi. Once the tank starts emptying, be ready to shut it off to airlock it (and shut the compressor off when you do). Ideally you want a very big volume of air to move water in the pipe but not build up any pressure.

Without the returns being plugged, all the air is going to escape the returns and none of it will go to the drain. So you’ll need to blow the returns and then plug them as well as the skimmer, then try and blow the main drain.

 

[Newdude]

+1. That's the downside of compressors for this use. If there is the slightest leak anywhere in the system, the pressure is lost. With the returns, skimmers, etc open, the air will simply take the path of least resistance and leave the other legs full.