Main Drain/closing question

[19jmm68]

Hi there,
This is my first post. I live in Michigan.

This is the first year I have closed my own pool. I had a friend who is a 30 year pool owner help me. After we blew air into the main drain line.......and saw bubbles, we shut air off but left the drain valve open. So, we did not create an "air lock" in the drain pipe.

I am a little paranoid now since my research on the internet finds that its recommended that you close drain valve to make the air-lock.

My friend said he didn't bother closing the drain valve because he said that the drain shut off valve would not, by design, close completely and that eventually the air lock would not hold. ( I have shut off valves on both the drain and skimmer......but, they mostly function as diverters and not 100% seal up shut off valves)

My friend said the water in the pipe, after I blew air into it would equalize to the water level in the pool.....and since the drain line was not full and not capped at both ends, if anything were to freeze in the drain pipe, any ice expansion would have somewhere to go and not burst my pipes.

So, am I good....... or should I worry that I did not create an airlock. It sounds like I would not be able to create one that would hold even if I wanted to.

All my other lines(skimmer and returns are free of water and have anti freeze in them as well for insurance)

Thanks you for any helpful replies you can give me!
James

 

[Pool_Medic]

Unless you have a great valve, you can’t great that air lock, some use an expansion plug to try to seal it. If your pool is plumbed with rigid pvc, I woukd blow it again and use an expansion plug, if it’s flex pvc, I would worry.

 

[Texas Splash]

Hi James and welcome to TFP! In case you haven't already seen it, here's our closing page: Pool School - Closing an In Ground Pool.

I'm sure others will reply as well to assist.