Beer Won't carb?

[Hwk-I-St8]

I'm on my third batch of beer since I started kegging. The first two went really well. To carb, I ran 25 psi for 48 hours, then dropped to 12 for 48 hours then dropped to 10. The carbonation was very noticable after the first 48 hours and after the two days at 12 was pretty much where I wanted it.

This third batch has had the 48 hours at 25 psi, another 24 hours at 12 psi and appears to be absolutely flat. No sign of carbonation at all.

This one, like the others, is in my kegerator at 37 degrees. It was cold from a cold crash when it went into the keg. The only difference is that the other two were NEIPA's at about 5.5-6% abv, this is a straight up IPA at 6.3%

Any clue why this is so stubborn to carbonate?

 

[Pappers_]

Could be a leaky keg.

 

[SGTSparty]

No sign of carbonation at all means either the keg isn't getting CO2 (check that your valves are turned on, your tank isn't empty, your disconnects are attached, all that basic stuff) or isn't holding pressure long enough for the CO2 to be forced into solution, likely a leak in the system as Pappers_ suggested.

First suggestion is to pull your PRV and make sure your keg is getting C02. If it is, time to go leak hunting unfortunately.

 

[Hwk-I-St8]

I know it's getting and holding pressure. I pressurized and purged via PRV when I first began the carbonation process. I also, out of habit, do this to verify no leaks whenever I connect a keg:
Pressurize to 25 psi
Close the CO2 tank valve
leave for 30 minutes to verify that the pressure doesn't drop
Turn CO2 tank back on

I also check it periodically to make sure all is well. It was a steady 25 for 48 hours. I had to purge with the coupler PRV to drop it to 12 (after adjusting the regulator). There was clearly pressure in the keg at that point.

It also serves beer just fine...it's just flat.

Honestly, at this point I'm baffled.

I did have one thought: If I had the post-regulator ball valve closed, the regulator would show 25 psi even if it wasn't 25 at the keg. I usually only use that valve if I need to do a quick disconnect of the coupler, CO2 or Serving hose. I did do that for the change from 25 to 12 psi because I had a penny in the serving line connection to keep the 25 psi pressure off my serving hose and tap. But at that point it should have been exposed to 25 psi for 48 hours and showed pretty decent carbonation (at least it has with the previous two kegs).

 

[TastyAdventure]

Does it cause problems if your keg is too full and you try to carb? I filled mind to the brim and now it won't hold a carb, but I'm wondering if it's just not taking one at all because it's too full. I'm pretty sure there's no leak...
It was working fine on the last batch I used it for

 

[day_trippr]

The larger the beer/CO2 interface area the faster CO2 can pass along to the beer.
If you're filling a corny keg past the "shoulder" of the cylindrical keg wall that interface gets smaller and smaller, so the rate of carbonation is going to be smaller...

Cheers!

 

[seatazzz]

+1 to what day_trippr said. Force carbing needs a lot more surface area with the beer to work. I would try ramping up the regulator to 25 or 30, then rocking the keg gently for a minute or two to get as much c02 contacting the wort as possible. Yes, you CAN over carb this way, but if you don't go insane with it, it should work. Force carbing to the volume you want takes practice, and patience. Let it sit for an hour, purge, then rock it again. You may need to purge it some more if you get a lot of foam. After the last purge, let it sit for 24 hours then try tapping it again. When you are filling your keg, you want to make sure there's at least 1 inch of space between the bottom of the IN dip tube and your beer. Any higher and you risk getting beer sucked back into the regulator.