Are my valves holding pressure correctly?

[user 141939]

I've been messing around with my dual valve regulator tonight. I hooked up a un-pressurized keg full of beer and pressurized up to 20 PSI. Not trying to carbonate but just to seal the lid so I can store the keg.

I then loosened the valve (turning all the way to left). On the last turn or so, the pressure on the gauge dropped to zero. This is with the line still attached to the keg, this seemed odd.

I removed the line from the keg, cranked the pressure in the line back up to 20, and again loosened the valve and pressure dropped to zero.

Is that normal? I feel like the gauge should remain at 20 until I do something to release the pressure. I know there is a lot of play in the that knob, meaning I have to turn it quite a bit to the right before pressure builds. And I can back it off almost all the way (to the left) without the gauge dropping at all, it's only the last turn or so, and the gauge will drop completely to zero every time regardless of what I have the pressure set at.

It's doing it with both valves. Perhaps it's normal? I've sprayed and sprayed with star san and don't see any leaks anywhere.

 

[day_trippr]

What make regulator? There are a few regs (eg: Taprite) that integrate the PRV in the regulator body, so when you turn the pressure down, the PRV automagically relieves the down-stream pressure to bring it in line with the regulator setting.

If your regulator has shut-off valves on the low pressure outlets, and those valves have built-in "backflow-preventers" (aka "check valves") even while the dialed-down regulator is showing no pressure, the kegs should still be pressurized - the gas inside will be "trapped" by the check valves. You could test this easily enough...

Cheers!

 

[user 141939]

What make regulator? There are a few regs (eg: Taprite) that integrate the PRV in the regulator body, so when you turn the pressure down, the PRV automagically relieves the down-stream pressure to bring it in line with the regulator setting.

If your regulator has shut-off valves on the low pressure outlets, and those valves have built-in "backflow-preventers" (aka "check valves") even while the dialed-down regulator is showing no pressure, the kegs should still be pressurized - the gas inside will be "trapped" by the check valves. You could test this easily enough...

Cheers!

It is a Taprite regulator. So sounds like you are telling me that it is doing what is expected?

Also, on a more basic note. What is the point of using the check valves? I've been perusing different how-tos tonight, a lot of them say to close the check valve, set the pressure to where you want it, and then open the check valve.

I've honestly never used that thing and just always keep it open. I just hook my lines up to whatever with it open and use the knob to set my pressure.

 

[day_trippr]

Yes, Taprites have that 'feature' built-in. You're good on that count.

Next, terminology time:
A "check valve" is not something you can open and close. That device is called a "shut-off valve" or a "stop valve", has a handle, and is found on the low-pressure side of a regulator, or used in multiples on gas manifolds.

A "check valve" - aka "backflow preventer" - is typically a lightly-spring-loaded BB-size metal ball traveling in the down-stream port of a "shut-off valve" so equipped (not all "shut-off valves" have "check valves").

If the pressure on the "down stream" side of the open valve is higher than the "up stream" side, the ball is shoved against the spring to a stop point that seals the port against gas (or liquid) flowing "backward". This can be a regulator-saver should one overfill a keg, put pressure on the sealed keg, then inadvertently reduce the pressure in the line.

As for the shut-off valve, you'll eventually find reason to use it. I use mine all the time - but then my regs don't have that Taprite automatic PRV feature and instead use manual PRVs. On those, it's handy to close the shut-off valve when setting a new pressure, using the manual PRV to discharge pressure if going to a lower setting, before opening the shut-off valve...

Cheers!

 

[user 141939]

Outstanding. Thanks so much for your quick and thorough help. I will continue to not use the shut-off valve then. Until I find a reason to. And I can stop worriing about the regulator.

I'll play around with that second bit of your first response, the bit about the check valves as well.

 

[day_trippr]

Cheers!