Nitrogen Airblock

[blackjaxbrew]

So I purchased a dual airblock, and I use one for coffee which needs to be around 35-40psi. I then have a beer on tap at the same pressure. Today I had back fill into the air lines, from both my beer and coffee, is there a special airblock I should purchase or just switch to a dual regulator ?

 

[Transamguy77]

What kind of air block? Could you just use a wye?

 

[day_trippr]

Greetings, @blackjaxbrew! Welcome to HBT!

Please correct me if I'm getting this wrong, but from what I gather you have a single regulator feeding a one-in/two-out manifold serving kegs (?) holding beer and coffee, and somehow you had one or both liquids back up into your gas lines. And you're looking for a solution, possibly a "check valve" aka "backflow preventer".

The thing is, you should not have fluid backing up in gas lines, ever. The only way that should be able to happen is if a gas port on a keg is submerged in liquid - not uncommon if a keg is over-filled, but lets face it, that's a user-induced error. Adding a check valve is a good idea as a safety measure to protect regulators from being gunked up, but it's not a panacea.

Anyway...many gas manifolds that have shut-off valves for the outputs integrate back-flow preventer valves inside the shut-off valve assemblies, like this one:
https://www.amazon.com/Weekend-Brewer-Splitter-Distributor-Integrated/dp/B01N78UHWUAll of my gas manifolds are so equipped.
Alternatively there are in-line add-on check valves available, like these:
https://www.amazon.com/XtremeAmazing-Check-Valve-Wear-Resistant-Liquid/dp/B07Z1Q52ZRYou could insert one of these in each of your two gas lines...

hth

Cheers!