Gotta push down on QD's to get gas into keg?

[Gabba]

Well, I just attached some new quick disconnects to a new keg - only heard a very faint sound of gas moving. I pushed the QD down and then heard a much larger sound of gas moving into the keg.

The QD is sitting firmly on the post; it won't go any further down, but for some reason, pushing on it as the gas is on seems to help and allow much more gas inside at a time.

The poppet inside is the kind with those tri-legs holding it inside - never had this kind before, so I'm not sure what to expect

Is this normal?

Gas goes in if I leave it be, but it's only a very faint sound; it sounds much louder if I push down on the QD

 

[drewmedic23]

you said everything is new?
The only thing I can think of is the little springs may be a little tight requiring more pressure to move them. Otherwise, I'm not sure

 

[Clonefan94]

Are you expecting a big sound? A lot of headspace? I'm just wondering because could it be that as you are pushing down, you are breaking the seal of the QD and gas is escaping as well?

It could be the post on the new QD missed quality control at the factory though. or got messed up in assembly.

 

[The_Canmancan]

Perfectly normal. You have to remember that you have the pin thing inside the QD, with a spring on it, and you also have a spring on the poppet valve on the keg. So you basically have two springs pushing against each other. They are in equilibrium when you aren't pushing on the QD. When you push on the QD, you are pushing both springs into a more compressed position, opening the valve more. This is why you are getting more/faster flow when you push down on the QD.

I hook it all together, set the pressure, and let it be (after carbonated of course). It all works just fine.

 

[dbrewski]

Try it with a different disconnect. Some of them are just off a bit and very hard to snap down. If a different one works better it's the disconnect. If not, could be the post. I've experienced both. I had one so hard to press down I sat a piece of wood over it and smacked it with a hammer. I busted it, oops, but it didn't work anyway.

 

[day_trippr]

Perfectly normal. You have to remember that you have the pin thing inside the QD, with a spring on it, and you also have a spring on the poppet valve on the keg. So you basically have two springs pushing against each other.[...]

No, that's not correct. The QD spring is there only to close the plunger/valve, not to fight with the poppet spring. The length of the plunger in the QD is designed to "hard stop" against the screw-in cap, at which point all of the downward movement of the QD translates into driving the poppet downwards...

Cheers!

 

[The_Canmancan]

No, that's not correct. The QD spring is there only to close the plunger/valve, not to fight with the poppet spring. The length of the plunger in the QD is designed to "hard stop" against the screw-in cap, at which point all of the downward movement of the QD translates into driving the poppet downwards...

Cheers!

1. It would be to open the valve, it's already closed before you attach it to the post.
2. It is widely known that both the "plunger" and the poppet work in unison, not against each other. The only time the "plunger" hits a hard stop is if you are pushing down on the QD to force it all the way open. Same for the poppet. When the QD is attached and not touched, the system is in equilibrium. Unless one spring is stronger than the other, both valves are equally open.

 

[day_trippr]

1. It would be to open the valve, it's already closed before you attach it to the post.
2. It is widely known that both the "plunger" and the poppet work in unison, not against each other. The only time the "plunger" hits a hard stop is if you are pushing down on the QD to force it all the way open. Same for the poppet. When the QD is attached and not touched, the system is in equilibrium. Unless one spring is stronger than the other, both valves are equally open.

Well, I'm sorry, but you're quite wrong. All you'd have to do is examine a drawing of a ball lock quick disconnect to see that the plunger spring does not have to fight the poppet spring, as the plunger does run out of travel well in advance of activating the poppet. It's a sound design, unlike whatever you're thinking of...

Cheers!

[edit] I have two types of QDs in my systems, and I just took one of each type apart. One type relies on the plunger stem directly contacting the screw-down cap to limit travel to a little more than an 3/16", and once that happens all down-ward movement of the QD on a post is on the poppet - the plunger can't move any further, unless you loosen the cap.

The other type of QD has a thinner plunger stem that slides within a sleeve molded in the screw-down cap. Without a spring in place, it travels quite a ways - too far to move the poppet downwards sufficiently. However, the plunger spring itself is fully compressed - winding turn solidly on winding turn through its length - against the cap in the same 3/16" of plunger travel, thus the plunger can't move any further.

I'll also note that the plunger springs on both QDs are way softer than the poppet springs I checked. There's no way the QD plunger springs could reliably over-ride the poppet springs...

 

[The_Canmancan]

Well, I'm sorry, but you're quite wrong. All you'd have to do is examine a drawing of a ball lock quick disconnect to see that the plunger spring does not have to fight the poppet spring, as the plunger does run out of travel well in advance of activating the poppet. It's a sound design, unlike whatever you're thinking of...

Cheers!

http://www.draft-beer-made-easy.com/corneliuskegvalves.html

Check out the short paragraph just above the second picture. The key word there is "balanced". Ergo the springs work together. There's no hard stop in the QD.

Also, just for the record, I confirmed this with KegWorks when I bought my kegerator.