hiss from pressure release valve - normal?

[founddrama]

Short version: is it normal for there to be a faint hiss from the pressure release valve on a ball-lock Corny keg?

I'm new to kegging (this is my first batch) and I've made a number of mistakes along the way already, but I'm learning. My latest hurdle seems to be that I've got a persistent faint hiss from the pressure release valve on the keg itself (NOT the regulator). I've sprayed some Star San around the valve and sure enough, it bubbles. The valve is the "flippy switch" kind, not the pull-ring kind. (Also: I've noted a big difference in hiss between when the valve is in the open vs. closed positions.)

I've unscrewed the valve and inspected it; as far as I can tell, it looks like it should be fine. I've treated it with keg lube and re-seated it, but this doesn't seem to have made a difference. This appears to be the case with both of the kegs that I have in my rotation.

The closest thread I've been able to find on this topic is this one.

Have I missed something with these? Or am I just with back against the wall and need to pick up some new PRVs?

 

[user 4295]

The only time it's normal for a pressure relief valve to allow gas to flow through it is if the pressure inside the keg is too high. Otherwise, it's faulty, or the seat in the keg lid is damaged in some way.

 

[day_trippr]

Not a fan of the "flippy switch" PRVs. Don't want to discourage the OP but out of 14 kegs here only one came with a "flippy" and it caused enough grief that I replaced the lid with a pull-ring PRV...

Cheers!

 

[founddrama]

Not a fan of the "flippy switch" PRVs. Don't want to discourage the OP but out of 14 kegs here only one came with a "flippy" and it caused enough grief that I replaced the lid with a pull-ring PRV...

I wouldn't call it discouraging. My opinion of the "flippy" PRVs isn't very high to start with. If replacement PRVs are in my future but it also means a properly sealed keg then I'm all in.

UPDATE: Replacing the old PRVs did the trick. File that one under "new kegger's guide to kegging"!

 

[ncsuwerewolf]

If keg lube didnt fix it its time for a new relief valve. They dont last forever. Like any component with a rubber contact they wear out over time. If you do replace i would lube that. Always lube rubber to help keep the dryrot down.