Loosening unions to close ball valves during closing line air lock

[Sickfickleduck]

I was told that loosening the unions for the ball valves for the main drain and skimmer will allow them to close all the way if they are struggling to when it comes time for closing. My question is two fold.

1. Why is it the case that the valves won’t close if the unions are not loosened.

2. I’ve attached a photo. To my understanding you need an airlock for over the winter when blowing out the lines for the main drain. If I blow out the line and close the ball valve but the union is loose to allow the ball valve to close all the way doesn’t that mean that I lose the air lock?

I understand this might be a little
Hard to follow so if clarification if needed please let me know.

Thank you

 

[ajw22]

Ball valves stick and warp as they age and eventually the handles break. We recommend always using diverter valves and not ball valves.

You will not maintain an air lock with loose unions.

 

[Sickfickleduck]

Ball valves stick and warp as they age and eventually the handles break. We recommend always using diverter valves and not ball valves.

You will not maintain an air lock with loose unions.

They would not be completely loose maybe a half turn to allow the valve to close, does that still cause issues?

 

[ajw22]

They would not be completely loose maybe a half turn to allow the valve to close, does that still cause issues?

If it allows air in it prevents the air lock. How will you know if you have a good air lock?

 

[JamesW]

You can slightly loosen the union nut to close the valve completely if necessary and then you would retighten the union nut.

You can listen in the pump basket for an air leak to verify if the air lock is complete.

You can put a plug into the suction hole of the pump.

You can use soap spray on the valve to see if any air is escaping at the valve stem or union nut.

 

[Sickfickleduck]

You can slightly loosen the union nut to close the valve completely if necessary and then you would retighten the union nut.

You can listen in the pump basket for an air leak to verify if the air lock is complete.

You can put a plug into the suction hole of the pump.

You can use soap spray on the valve to see if any air is escaping at the valve stem or union nut.

So after closing the valve open the pump basket and I should be able to hear if there is an air leak?

 

[Sickfickleduck]

If it allows air in it prevents the air lock. How will you know if you have a good air lock?

I would think a quarter turn on a union and then closing it after closing the valve would be a negligible amount of air being brought in. Again I’m no expert but i would think it wouldn’t be enough to completely break the air lock

 

[ajw22]

it wouldn’t be enough to completely break the air lock

I think an air lock is binary. I don't know how you can have half an air lock. Either there is an air lock or there is not. Without an air lock under pressure water will have leaked back into the pipe while you are tightening the union.

Best of luck with what you plan to do.

 

[wireform]

Maybe you can lube the ball and socket aka union nut/collar and then snug it up before air locking, as @ajw22 said it either is or isn't but halfway won't work.

 

[JamesW]

Slightly loosening the nut just reduces the compression of the ball and the sealing rings, it does not ruin the seal.

It should still be sealed; it just allows the ball to rotate with lower friction.

Once the air is cleared, the seal should hold.

If it leaks, the leak should be small enough to be insignificant.

Then, tighten the nut to make a tight seal.

Listen in the pump basket for the sound of air escaping.

Use a rubber plug in the pump inlet to ensure a tight seal if the valves leak.

Use soapy water, Mr. Bubble etc. on the outside to verify no leaks.

Ingredients:
A clean glass cup
8 oz of distilled water – Minerals and particulate in normal tap water can hamper the making of larger bubbles, but it can still work if you don’t have distilled.
One tablespoon of dish soap – Any type is fine!
0.5 Tablespoon glycerin – This is what strengthens your bubbles!
Steps:
Step 1 – Stir all of your ingredients together in the glass cup.
Step 2 – Wait! Let the bubble solution sit for 24 hours.
Why is time so important? It allows the glycerin to fully mix together with the other ingredients. The glycerin is important for keeping the water from evaporating from your bubble and prematurely popping it.