Fermizilla Cave In

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trenta

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Hi
When I cold crash my fermenter caves in. I even put 5psi in it before cold crashing and it happened again. Any ideas?
I've tested the fermizilla and it has no leaks
Thanks in advance
 
Sounds like you have a decent seal! The beer and co2 both contract when chilled. Total initial volume loss should be around 2 litres for a single batch. The beer will absorb more co2 when cold, and the longer you hold cold temps the more it will absorb. Top up with more co2 if you like, before or during cold crashing. Or don’t.
 
Sounds like you have a decent seal! The beer and co2 both contract when chilled. Total initial volume loss should be around 2 litres for a single batch. The beer will absorb more co2 when cold, and the longer you hold cold temps the more it will absorb. Top up with more co2 if you like, before or during cold crashing. Or don’t.
So the cave in is common or do I need a new fermenter?
 
You need about 15~20psi warm CO2 saturation before you cold crash, or just put your gas on and leave it pressurized as you cool, then it'll be carbonated, or if you don't want to carb it up, put your co2 on really low psi and leave it attached as you cool.
 
Put more pressure in before crashing and even potentially monitor it to top it up. It will be worse if you have less beer inside too (larger gas space).
 
Hi
When I cold crash my fermenter caves in. I even put 5psi in it before cold crashing and it happened again. Any ideas?
I've tested the fermizilla and it has no leaks
Thanks in advance
Raises an interesting topic of carbonating the beer in the fermenter. Firstly if you are going to bottle, (this won't apply to kegging as you can add and release CO2) if you add top pressure to allow for the solubility of the gas being drawn into the beer as it cools, how do you actually know how much CO2 is in the beer? We know that the gas dissolved into the beer is equal to the gas in the head space and there is a chart which gives an approximate amount of CO2 in the beer at 1ATM at a given temperature.
So when the top pressure is released (if bottling) does that then release the dissolved CO2 immediately to balance with the 1 ATM?
 
Mine did too. Put more pressure in it. They'll cop 2.5 bar (about 35 psi) before the PRV hisses at you.

Take it easy though. Delta p has caught a few people out lately..
 
Raises an interesting topic of carbonating the beer in the fermenter. Firstly if you are going to bottle, (this won't apply to kegging as you can add and release CO2) if you add top pressure to allow for the solubility of the gas being drawn into the beer as it cools, how do you actually know how much CO2 is in the beer? We know that the gas dissolved into the beer is equal to the gas in the head space and there is a chart which gives an approximate amount of CO2 in the beer at 1ATM at a given temperature.
So when the top pressure is released (if bottling) does that then release the dissolved CO2 immediately to balance with the 1 ATM?
In the 2 years since I moved to kegs (what a wonderful experience it has been haha) I have always carbonated in the fermentor during ferment and then tranferred to the keg. I know there's plenty of people who are against this (I think you in particuar WEAL ;)) but let's not go in to that now. There was only one time that I have bottled. This was with a ginger beer. I fermeneted at 25degC and 25+psi, cold crashed and tranferred the carbonated beer into PET bottles using the carb cap and tee set up (similar to proper counter pressure bottle filler) and it worked out reasonably well. It could have a little more fizz but I'm pretty happy with it. It's definitely not light on the fizz.
 
So when the top pressure is released (if bottling) does that then release the dissolved CO2 immediately to balance with the 1 ATM?
Temperature and agitation of the liquid comes into play, the colder it is, the slower the gas is released over a given amount of time.
 
In the 2 years since I moved to kegs (what a wonderful experience it has been haha) I have always carbonated in the fermentor during ferment and then tranferred to the keg. I know there's plenty of people who are against this (I think you in particuar WEAL ;)) but let's not go in to that now. There was only one time that I have bottled. This was with a ginger beer. I fermeneted at 25degC and 25+psi, cold crashed and tranferred the carbonated beer into PET bottles using the carb cap and tee set up (similar to proper counter pressure bottle filler) and it worked out reasonably well. It could have a little more fizz but I'm pretty happy with it. It's definitely not light on the fizz.
I am not against carbing up in the fermetor, in fact most breweries do, usually they will cap the fermentor for the last point or 2.
There is actually a good podcast about the effects of spunding, this is only a short, I think the original went for about 1 hour.
Sorry never included the clip.
Temperature and agitation of the liquid comes into play, the colder it is, the slower the gas is released over a given amount of time.
I allow for that Grok when I am bottling beer 21 litres looking for 1.8 volumes of CO2 at 2C I have 1.59 volumes the approximate amount of sugar needed for achieving 1.8 volumes is 17.5 grams according to the chart. What I do is add another 50% of the sugar 25-26 grams this extra allows for the loss of CO2 going into the bottling bucket, loss of CO2 going into a warm bottle. Nothing scientific coming to that conclusion just trial and error. But it is a genuine question, 'How quickly does CO2 leave a solution when top pressure is released? Is it as fast as the pressure release a few seconds or being as it is slow to dissolve into the solution is it slow vacating it?
 
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I am not against carbing up in the fermetor, in fact most breweries do, usually they will cap the fermentor for the last point or 2.
There is actually a good podcast about the effects of spunding, this is only a short, I think the original went for about 1 hour.
Sorry never included the clip.

I allow for that Grok when I am bottling beer 21 litres looking for 1.8 volumes of CO2 at 2C I have 1.59 volumes the approximate amount of sugar needed for achieving 1.8 volumes is 17.5 grams according to the chart. What I do is add another 50% of the sugar 25-26 grams this extra allows for the loss of CO2 going into the bottling bucket, loss of CO2 going into a warm bottle. Nothing scientific coming to that conclusion just trial and error. But it is a genuine question, 'How quickly does CO2 leave a solution when top pressure is released? Is it as fast as the pressure release a few seconds or being as it is slow to dissolve into the solution is it slow vacating it?

How quickly does your coke or beer go flat when you pour it into a glass (ie. removing ALL pressure). It’s slow right? If you step the pressure down I would say the rate of change is even slower as the pressure differential is lower.
 
How quickly does your coke or beer go flat when you pour it into a glass (ie. removing ALL pressure). It’s slow right? If you step the pressure down I would say the rate of change is even slower as the pressure differential is lower.
I think many homebrewers have experienced that. Over carbed pour into a jug and wait for the CO2 to vacate, slightly over carbed bang the glass to drive out the CO2. For the home brewer trying to carb a bottled beer it is only going to be achieved by T& E.
Off topic I know so to the OP I have Apollo's and have a couple of times sucked in the sides of the fermentor, no harm done.
 

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