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Blowoff Cap Leaking

Ok, I had to put on one of those snap-on type orange blowoff caps ( the one that has two antenna looking plastic protrusions where one is for 3/8 tubing and the other fits 1/2 inch tubing) on my 6.5 gal carboy. I did this because with the hop sediment and large starter I ended up going over my expected volume .

So I have a 1/2 inch id hose on the cap because I was out of 3/8 and I wasn’t expecting to have to use it.

Well 9 hours into fermentation it’s blowing off co2 like crazy. I also noticed a slight hissing sound. I noticed small bubbles forming under the cap and slowly dripping down. I quickly grabbing a paper towel and star san and wiped the outside down. I took some duct tape, out of fear of the cap blowing off and hoped to fix the seal.

Well now the tape is getting wet and if I press the duct tape some of the blow off drips down.

It’s bubbling in the gallon air lock like crazy but I’m worried about this other leak. This has never happened with this cap before.

Should I be worried I ruined the beer or is everything ok? And should I remove the duct tape or just leave it until I get ready to transfer or when the vigorous ferm settles?

The beer itself is fine. The gas is still coming out under pressure, so there’s no chance of outside contamination coming in. That mess is going to get nasty though. Is it going to be contained with something like a swamp chiller? You’re probably just going to have to ride it out for the next few hours, and it will subside. Once active fermentation slows a bit, the cap will hold better. I’ve had a bucket lid pop open after the airlock clogged. It had blown overnight was was still barfing when I had to leave for work. When I got home it had settled; I wiped-down the bucket rim with star san, and put on a clean lid and airlock. Beer was still awesome. (Hefe w/blackberry)

I’m not clear on what’s going on with the 1/2" hose though… Why isn’t that letting off the pressure? is it clogged? maybe you just need to clean it? The other end is in a bucket of star san or other sanitizer solution, right? The gas should be escaping through the path of least resistance, so it’s surprising that the cap rim is less resistance than a 1/2" ID hose.

Finally, I’ve always thought those caps were for racking, or possibly temperature probing, I’ve never thought to use them for blow-off, but I guess it works.

It’s sold as a blow off cap from another company.

It’s not leaking too bad. If I squeeze the duct tape I’ll get a drop or two that come out from one side. Nothing that is running to the carpet.

I guess when the krausen starts to recede I’ll just remove the duct tape and clean and star san the area and retape just to help with the seal.

Day two and it’s still bubbling away like mad.

If I’m not mistaken, I believe the orange cap is for 5-6 gallon carboys. The 6.5 gallon carboy cap is red. Could be why it’s leaking.

Those caps always leaked for me, too. A zip-tie or hose clamp helps. I ultimately switched to a drilled bung ( … illed.html), which seals better with less fuss, and you can stick an airlock in it or hook up a blow-off tube.

But positive pressure is keeping your beer safe at this point.

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