Blowoff Suck Back

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Lyrebird_Cycles

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Rightio! Do the vacuum breaker valves just let air in?

The vacuum breakers would let air in if they actuated but I've never seen one actuate from normal temperature changes in the beer, they're designed to protect against cloth eared gits rinsing hot tanks with cold water and such like.
 

Bribie G

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I caught the brew at the end of the fermentation and fitted a simple plastic bag, tightly squeezed into the hose with that green garden tie wire and squashed flat, it hasn't blown up like a balloon but there's easily a litre in there - I'll drop the whole thing to -1 probably starting tomorrow.

blowoff bag.jpg
 

good4whatAlesU

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malt junkie

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Make an air lock chamber/jar, two hoses through the lid one just long enough to go through the lid the other 2/3 to the bottom of the jar, short goes the the ferm, long goes to container of liquid.
Job done.
 

nosco

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I did think about that at first. I wonder what happens to the 02 that is in the chamber to start with? I guess it depend on the size of the chamber. When you CC wouldnt it still be sucking in air?
 

rossbaker

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+1 for the carbonation cap idea with a 2-3l pet bottle. You could manually purge it with co2 to be certain no O2 gets sucked back in. I'd be interested to see how much the pet bottle implodes.
 

RobB

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Depending on your starting head space, this could be a plug and play solution.
filter housing.jpg
It's an inline filter housing with push fittings, about $30 on ebay. At 10"x2.5", this would add about 750mL to the volume of your blowoff hose. This should be enough to allow you to start with 11L of headspace and chill from 20C to 0C.

If you start with a larger head space or are chilling from a higher starting point, you will need more volume than this housing provides, but I still think that adding a large inline chamber along the blowoff is the simplest way to go. A short length of 100mm PVC pipe with end caps could be a good starting point for a ghetto solution.
 

Bribie G

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I think my quick and dirty method has worked pretty well. When I took my 2 deg C brewbucket out for kegging just now, there was still a fair bit of "puff" left in the blue bag despite the cold crash.
blowoff bag2.jpg


When I started transferring, the bag got sucked in quite tightly and runoff slowed so obviously airtight enough for purposes. My next move will be to find a more sophisticated bag, and maybe a hose clamp.

blowoff bag3.jpg
 
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I thought you'd connect your transfer hose to a beer quick disconnect rather than have it run inside the keg Bribie.
Gas quick disconnect to let the air out as the keg fills.
 

Bribie G

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The keg is initially filled with 100% CO2 and as the liquid level rises the CO2 is expelled, pushing out any stray oxygen that is trying to get in from the other direction, damn its little shoes and breeches.
At the end of the fill, the headspace is immediately flushed with CO2.
 

nosco

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Does it have the size written on the side Bribey? Id love to replace the original. Its a bit shit init.

Are you still using the pickup tube with it?
 

Bribie G

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It's a STM 3/8" with a couple of codes stamped on the sides.

316. 1A6

1000 WOG

Obviously assembled by a Greek dude.

Bits and bobs from Reece etc but youll need to play with rubber grommets and o rings. A forum member made me up a bulkhead fitting that the valve screws into but you might want to check how other BB users have adapted Ball valves.

I never found the racking arm much use and it can't be used with the ball valve. I get a good keg full per brew, a couple of glasses to test out of primary and about a litre of yeast in the cone that I simply run out of the tap, so quite happy.
 
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nosco

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It was a good idea at the time but i think i might pop the bung before it inflates much more. I put some dry hops in down the bung hole to try and minimise air as much as i can. That kicked up a heaps of CO2 which hopefully flushed out any air.

My other stainless fermemnter has a weld less keg post on it so it should work better on there.
Im hoping to catch enough CO2 for a CC and for the transfer to keg.
20171020_171019.jpg
 

nosco

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Seems to be working with no leaks. It inflated to this size in about 30 but it hasnt changed an hour later.
 
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It was a good idea at the time but i think i might pop the bung before it inflates much more. I put some dry hops in down the bung hole to try and minimise air as much as i can. That kicked up a heaps of CO2 which hopefully flushed out any air.

My other stainless fermemnter has a weld less keg post on it so it should work better on there.
Im hoping to catch enough CO2 for a CC and for the transfer to keg.View attachment 109044

There's a bit going on in that photo nosco, so much to observe. :)
Are you using a party balloon for your 'suck back sack'?
Your fridge has got me intrigued, have you extended a bar fridge or something similar?
That spaghetti would go great in a bolognaise.:D
Love the wheels on the fermenter.
 

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