Air locking a main drain without a shut off valve at the equipment pad:
After a botched opening by a local pool company leaving me to complete the opening myself and a summer of maintaining my own pool, I decided that closing the pool might be something I could try. I spent countless hours reading blogs, articles and watching Youtube videos trying to familiarize myself with the process and trying to transpose what I had learned to my own pool.
The
concept made sense – balance and clean the pool, bring it up to shock, drain the pool a few inches below the skimmer basket, drain the filter and pump, blow out the lines with a shop-vac or air compressor, quickly plug all the lines, airlock the main drain, throw the cover on and sit back and enjoy the fruits of my labor. Easy enough, right?
Well as I dove in deeper (pun intended), I quickly realized that my pool was slightly different than most of those I had read about or seen on Youtube. I could not figure out how my main drain connected to my system and more importantly how I would ever be able to blow it out. I had all the standard equipment – a pump, a DE filter, 2 pipes sticking out of the ground, but there were no valves I could open or close to direct water from the main drain. I knew the drain was down there, I just never considered the overall functionality of the thing.
After doing some more research, my attention was drawn to my skimmer. I read that often time’s main drains were plumbed directly to the skimmer. Sure enough, after lifting up my skimmer basket, there she was – in all her glory.
Before committing to closing my pool, I wanted to make sure that my shop-vac had enough juice to blow out the main drain. I read mixed results about my Rigid 6.5hp shop-vac successfully blowing out the main drain and as most people told me, it did not produce enough volume to get air all the way through the system. I could see some debris coming out of the main drain as I ran my vac, but after countless minutes of waiting, I never got any air bubbles. Furthermore, my testing showed me how quickly the water comes rushing back up the pipe leaving me doubtful that I would have the speed to quickly plug the line and get a good air lock below the frost line. Back to the drawing board.
I kept reading threads figuring I would stumble onto something when I finally found these: A rubber expansion plug with a built in schrader valve (same as a bike tire stem).
http://www.poolweb.com/no-10-winter-plug-with-valve-for-1-1-2-inch-fitting-with-blow-thru-valve
I quickly ordered one and it showed up at my front door a couple days later.
First I removed the cap and plugged the hole going to my main drain.
Next I grabbed my air compressor, set it at 25 PSI and hooked my female tire chuck
I seated my tire chuck onto the valve of the plug
And within a few seconds…… success! I let the bubbles go for about a minute for good measure.
After I was finished blowing out the drain, I screwed on the plastic cap and I was done.
After I blew out the main drain for the first time, I left the plug in for several days leading up to my actual pool closing just to double check that everything worked as planned. Sure enough, when I unplugged the drain, it was still full of air and the water came rushing up. At this point, I was confident enough to move forward with attempting to close my own pool!
My entire pool closing process:
1. The day before, I brought my chlorine levels up to shock and double-checked that the rest of my levels were balanced. My chlorine loss has been at 0 for months and the water temp was hanging right around 50 so I wasn’t too worried about adding anything else to the pool. I threw my dolphin robotic cleaner in and let it do its thing as well as giving the pool a good brushing.
2. The day of closing, I back-washed my DE filter and then turned my pump off and moved my valve to “recirculate”. I used my cover pump to bring my water level 2 inches or so below the skimmer basket by putting it on the top step in my shallow end.
3. After the water was below my skimmer, I pulled the 2 plugs out of my pump basket, opened up the relief valve on my DE filter and then pulled the plug on the DE filter and let all my water drain.
4. I then moved to my skimmer basket where I used the method illustrated above to blow out my main drain.
5. I then used the same method illustrated above on the second hole in my skimmer basket to blow air
back to the equipment pad / pump basket. I had someone stand there and let me know when there was no more water coming out. When the line was clear, I removed the rubber expansion plug with the valve and threaded in my Gizzmo. For good measure, I cut a foam pool noodle into little sections and stuffed them down around the Gizzmo.
6. Next up was my return lines. I went back to the equipment pad, reinstalled one of the pump basket drain plugs removed in Step 3 and screwed on a ¼ NTP male fitting for my compressor in the other drain port of the pump basket, screwed down the lid to create a seal and used my compressor at 25PSI to begin blowing out the return lines. Since my return lines are connected, I used a standard rubber expansion plug to plug up the first return and then plugged the second line while having someone turn the compressor off at the same time.
7. My next challenge was to blow out the abandoned Polaris line that was erroneously unplugged during my pool opening. Since it was capped off (shown in the image below), I had to use a hack saw to cut off the cap. Using my 6.5 hp Rigid Shop-vac, I blew the line out the line and plugged it using an threaded plug. I then recapped it at the equipment pad using a tight fitting PVC cap. I chose not to use any adhesive in the event it becomes unplugged again.
8. After all the lines were blown out, I walked around the pool looking for any bubbles or any signs that something might not have been sealed or plugged correctly. After I was confident everything looked good, I had someone help me put on our safety cover. Now I can’t wait to open her up next season!
In summary, the pool closing process was nowhere near the difficulty I thought it was going to be. The
concept is simple and once you understand it, the work required is very straightforward. The post "
The concept of closing an in ground swimming pool" coupled with the help of Catanzaro himself, really helped hit these concepts home and made me very confident in closing the pool. Thanks to the TFP community for my first successful year as a pool owner!
