how long to "naturally" chill 11ish gal of wort outdoors?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

mattdee1

Supporting Member
HBT Supporter
Joined
May 15, 2015
Messages
703
Reaction score
453
I've been actively all-grain brewing for 6 years and every batch has been chilled using the same copper immersion chiller I built back in 2015.

I would like to try brewing a 10gal batch of beer and chilling it right in the brew kettle using nothing but cold winter air.

I am able to find all kinds of stories and forum posts from homebrewers who claim to have done this successfully but what I absolutely cannot seem to find anywhere is some actual anecdotal data on how long I can expect the cooling from boil to pitching temp to take. The best I can find online are vague stories like "I just let it sit on the porch overnight." Well, what does that mean? If it's flame out around 11pm, does that mean pitching temp by 6am? 12pm? 2pm?

I know there are lots of variables, but let's assume an ambient temperature of mid-20s F. My gut feeling is that 10-11gal of boiling wort will take somewhere around 8-10 hours to hit 70F, but my gut feeling is worthless here for planning purposes.

Does anybody have any actual data to share? Even if different beer volume and different temperature? Any data is better than no data.

PS - I'm not looking for lectures on how bad the beer will be, how the hop utilization will be messed up, etc. I think I've read enough about all that.
 
I do no-chill (overnight chill) for all my brews... Cooling time will of course depend on the volume of wort and the outside temp.
But, 10-12 hours isn't too far off... I've gone 18 with a warm summer night... 😬

I do stove top BIAB and used to partially chill in a sink full of ice water before carrying outside to finish slow-chilling overnight. But my new kettle won't fit in my new kitchen sink :(

So now I just dump my hot wort into a plastic pail fermenter, slap on an s-type airlock and carry that outside... Next day I put the fermenter into a party tub filled halfway with water and drop in some frozen water bottles to get down the last few degrees to pitching
temp.

It always takes longer than you want. But it works. The more you can do enhance heat transfer, the better off you'll be...

Carefully wet down the hot kettle (don't get any inside) or use wet towels (replace or remove when dry) to add evaporative cooling. Make sure the kettle is sitting on a good heat sink, not a thermal insulator... concrete slab is better than a wooden deck, for instance... If you have a pool with shallow step, that giant water bath would be great...
 
It's going to mostly depend on the characteristics of the pot and temp/wind/what the pot is sitting on.

Boil you a batch of water and sit it outside and measure.
 
I think the data your looking for doesn’t really exist, there are too many variables to be able to replicate the data.

I had to do it my first 10 gallon brew because I didn’t think about a bigger wort chiller so when I was done around 11 pm in a higher teen low 20 night by 8 am was around 70. Now if you had some way to circulate that wort you might achieve that temp difference quicker.

Do you have a pump? Even using a cheap solar pump You could circulate your wort through the chiller you have now and put that chiller in a bucket of ice water, kind of like a counterflow just without the counter part.

Or just make an IC now and not worry how your going to chill your wort down.
 
Agreed...best bet is to replicate with water. If you want a first order estimate, I'd start here: Newton's law of cooling - Wikipedia
more fidelity than this and you'd need to know wind speed outside, and to model things like "forced convection" and "radiation" outside the vessel and "free convection" inside. Not a quick effort.
 
If you put a fan blowing cold air on the outside of the pot, you can increase the heat transfer by a factor of 10 or more - so wind matters - and that’s why it’s difficult to get an accurate or consistent answer.
 
Last edited:
I think the better answer in this case is to invest a few dollars into HDPE cubes like the Aussie's do.

https://www.amazon.com/5-Gallon-Pla...ld=1&keywords=HDPE+cube&qid=1611719505&sr=8-1
5.5g in each cube (they 'stretch' a bit when hot), cooling to ambient overnight. High temps sterilize the container, gasketed lids prevent outside contaminants from getting in. Either ferment in the cube (a cleaning nightmare), or transfer to your fermenter the next day... or the next week.

I regularly do 11g batches into two cubes, so long as there are no late hop additions (but that can be adjusted for), and they are ready to pitch the next morning. Easy peasy.
 
I am able to find all kinds of stories and forum posts from homebrewers who claim to have done this successfully but what I absolutely cannot seem to find anywhere is some actual anecdotal data on how long I can expect the cooling from boil to pitching temp to take. The best I can find online are vague stories like "I just let it sit on the porch overnight." Well, what does that mean? If it's flame out around 11pm, does that mean pitching temp by 6am? 12pm? 2pm?

You'll never get a definitive answer because outside is a constantly changing environment. For instance, last evening when I would have put the wort out to chill the temp was 5 degrees F. This morning it is -22. How long would it have taken to cool the wort to pitching temp? Impossible to be sure as while the temperature was falling, so was the wind speed. There was snow on the ground but how long was it there after I put the pot of wort onto it.
 
I live in an over 55 community, they have an ice machine for us so I use ice to cool my wort. I usually use my plastic deep sink, just pour a cooler of ice in, set the brew pot on the ice, and pour another cooler of ice in. We are moving so the deep sink is at our old place. I used a plastic tub this time and it didn't need as much ice. I let the brew kettle set there for a time, I was more, not worried not concerned but considering that the wort might be too cool. So I sat the brew kettle on the concrete, covered it with a towel, and left it overnight. The temp was supposed to be in the mid 60’s the next morning so It worked out perfectly for me. It is the first time I have let wort set for so long. We shall see how it works out.
 
Thanks all.

I had no illusions that there would be a "definitive" answer, just looking for real world experiences people have had.

Since the wind seems like a huge wild card, it would probably make more sense to use my garage instead of outdoors on the patio. It would take longer to chill but it would probably be much more consistent/predictable due to no wind and the thermal buffer of the attached house would mean less temperature fluctuation.

I am reluctant to buy more "stuff" if it's not necessary but I think I'll probably just go ahead and pick up a pair of those HDPE cubes and do this no-chill thing right. That way, being able to predict the timing isn't as important.

I've got several "house" beers that family members and friends dig a lot, and they're the basic ones without a strong late-hop component - blonde, amber, porter, etc. I make these a few times a year so I'd like to see if I can relegate them to this no-chill process because that process allows for a shorter brew day. Shorter brew day means more flexibility in choosing when to brew. And it all frees up the increasingly rare (for me) "full" brew days for beers that require whirlpooling, longer boils, etc. That's the plan, anyway.
 
Well, I gave it a whirl last weekend. When the boil was done, I just left the full 10.5ish gallons of wort in the kettle with the lid on, and pushed the brew cart to the corner of the garage. Ambient temperature in the garage was right around 0C / 32F give or take a degree or two. It took 17 hours to cool from 212F to high 60s. Beer is still fermenting; hopefully it turns out OK.
 
when my garden hose was frozen up I had to leave the wort to cool overnight in my brew pot. it was 10F outside, dropped in 2 one gallon blocks of ice to get temp down to 150F and after 8 hours it was cool enough to pitch my yeast. of course it was just sitting in the garage with the door closed so heat does not transfer as quick. next time if I do this I will leave the garage doors open a bit so that there is airflow against the pot.
 
when my garden hose was frozen up I had to leave the wort to cool overnight in my brew pot. it was 10F outside, dropped in 2 one gallon blocks of ice to get temp down to 150F and after 8 hours it was cool enough to pitch my yeast. of course it was just sitting in the garage with the door closed so heat does not transfer as quick. next time if I do this I will leave the garage doors open a bit so that there is airflow against the pot.

Yeah, having air moving around really speeds it up. I opened the garage door for the last hour in the final push to pitching temp and it did the trick.

Although, for me the long duration that I saw is not a problem in itself, I just want to have some sort of idea of what to expect so I can plan a little bit. It remains to be seen if the 17-hour chill leads to detrimental effects in the result, but intuitively I'm not concerned. If this works then it will really open up brewing opportunities for me because it means I can break the work up across 2 days and don't need to find a full 5-6 hour chunk of time to brew a beer.
 
I think the better answer in this case is to invest a few dollars into HDPE cubes like the Aussie's do.

https://www.amazon.com/5-Gallon-Pla...ld=1&keywords=HDPE+cube&qid=1611719505&sr=8-1
5.5g in each cube (they 'stretch' a bit when hot), cooling to ambient overnight. High temps sterilize the container, gasketed lids prevent outside contaminants from getting in. Either ferment in the cube (a cleaning nightmare), or transfer to your fermenter the next day... or the next week.

I regularly do 11g batches into two cubes, so long as there are no late hop additions (but that can be adjusted for), and they are ready to pitch the next morning. Easy peasy.
Hi. I have been looking for a product, The 20 L Hot Cube, several Aussie home brewer friends recommended, but I can't seem to find that product available in the US. Is the HDPE cube on Amazon rated to take hot liquids? I couldn't find anything about that in the Amazon description.
 
Back
Top