Keg cooling jacket experiment

The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
14° is pretty impressive, it's only a degree or two over ideal cask ale serving temp.

That’s right and it’s actually at the lower end of my preferred temperature range for cask ale.

The jacket does struggle a little when it comes to reducing the temperature but it seems pretty good at maintaining one. It is still quite early days in the experiment though so this might be a little premature.

I can say with some confidence though that this is not a solution to apply on the hottest day of the year a couple of hours before your big BBQ, it takes time. It’s also not very convenient if you have a dozen kegs like me, given you have to change the freezer blocks every six hours. It might be a good option for people with up to four kegs maybe?
 
A day later and...

The ambient temperature this morning was 17C, the beer temperature was14C. The ambient temperature has risen through the day to 20.6C, the beer temperature is still 14C.

Now it’s getting a little bit more exciting!

Inspired by your test, I thought I would measure my set up to see how it compared. Following advice from an earlier thread, I have got my King Keg in a tray filled with water. I've draped a towel over the whole keg with both ends in the water, and I've set a little usb fan on it to give it some welly. I then put another king keg next to it in the tray but this one is filled with water, has no towel on it and also no lid, so is pretty much ambient apart from the cooling effect on the bottom inch where it's in the water.

I only set this arrangement up yesterday morning and tested it at 6 p.m. yesterday evening. The water keg was at 17.2 and the beer keg at 14.8, so certainly an improvement but a fair way off your ice pack system. However, it is a set and forget system, so has some plus points. Unfortunately I turned the fan off by mistake last night, so I've missed the cooler night air, but to compensate I'm now trying a bigger fan, and I'll measure again this evening.

David
 
@MyQul bought a purpose built cooling jacket a few years ago and he was impressed with how good it was at doing its job, i think he used to use 2 litre plastic pop bottles i am sure hew will advise when he sees this.
 
Here a review of it

https://www.thehomebrewforum.co.uk/threads/cool-brewing-fermentation-bag.58966/



index.jpg



cool brew bag MAIN1.jpg
 
Last edited by a moderator:
Today’s report...

Ambient temperature is 23.6C
Beer temp is 15C

Now that’s more like it!

Here in sunny Suffolk at 6 p.m. yesterday evening I had
27.1 air temperature in the shed
21.6 in the keg with water round its feet
18.3 in the beer keg with the towel and 2 fans.

I was agreeably surprised at how refreshing and enjoyable beer at 18 C is. I suppose it's the relative difference that matters, but certainly for a dark English bitter 18 was very comfortable.

I've now taken the water filled keg out of the water tray and will record its temperature this evening. It's interesting that just by having an inch of water around its base there was a reduction of 5.5 C compared with ambient.
 
In the pockets for the ice blocks it would be good to have something that'll thermally bind the blocks to the barrel - like bags of gel or water.

I’ve been thinking about this because it’s a great idea. My thinking is that a waterproof bag containing something could be taped on the inside of the pocket and in direct contact with the keg. The “something” could be water but this will just pool at the bottom of the bag so it needs a little structure - either more of a gel or many cells like an ice cube bag.

The gel might be formed from wallpaper paste (would this harden?), or use water retaining crystals, or maybe I just make a strong jelly - the kind you make for kids and trifles! I think I like the last idea best.

Thoughts?
 
this would have been good info a few weeks back to have time to make something.... anyway relocated some bottles to cool down today's brew.

20200731_180607.jpg
 
Here we go...

Ambient temperature is 27C
Beer temperature is 16.5C

I’m calling that a win.🏆🥇

10.5 degrees reduction is very impressive and English style beers as I discovered yesterday taste great at 16

My figures for yesterday are not as good, though not hopeless

Air temp 29.8
Water, in keg just sitting on the counter, a surprisingly low 24.4
Beer, in keg in tray of water with towel draped over and two fans, 20.4

While I'm happy with the reduction of 9.4 when comparing the beer with ambient, the beer was just too warm to be enjoyable whereas I think 16 would have suited my present brew perfectly.

Whatever the method I shall be glad when it's cooled down a bit.................
 
10.5 degrees reduction is very impressive and English style beers as I discovered yesterday taste great at 16

My figures for yesterday are not as good, though not hopeless

Air temp 29.8
Water, in keg just sitting on the counter, a surprisingly low 24.4
Beer, in keg in tray of water with towel draped over and two fans, 20.4

While I'm happy with the reduction of 9.4 when comparing the beer with ambient, the beer was just too warm to be enjoyable whereas I think 16 would have suited my present brew perfectly.

Whatever the method I shall be glad when it's cooled down a bit.................

That’s not bad. I’m assuming you use chilled water but if not you could try keeping water in the fridge/freezer in an old coke bottle or similar and replace/replenish the water in your tray with ice cold water.
 
That’s not bad. I’m assuming you use chilled water but if not you could try keeping water in the fridge/freezer in an old coke bottle or similar and replace/replenish the water in your tray with ice cold water.

No it was just water straight out of the tap (rising main, not roof tank). I probably could improve it as you say by using chilled water, but I'm trying to keep it as simple as possible without trespassing on fridge/freezer space if possible!

All in all though, I'm encouraged. These hot spells are a very small percentage of the year's weather and I can put up with a bit of warm beer as long as it doesn't happen too often.
 
I think this will be my last post on this thread by way of an update because I’ve learned how the jacket performs. Today’s temperatures:

Ambient 21.6
Beer 15.5

So the original design does help keep your keg cooler than the ambient temperature by at least 4C and by as much as 10C, depending I think on the duration of the temperature spike.

The jacket does struggle to reduce the temperature by more than about four degrees but is far more effective at moderating temperature increases, especially if they are short lived.

The design is pretty cheap and is quick and easy to make but changing the freezer blocks every six hours is going to become a chore.

If you have up to four kegs and can be arsed to keep changing freezer blocks this might be a solution for you. If like me you have many more kegs, or if you can’t find the enthusiasm to keep changing freezer blocks, or if you want a bigger temperature differential/temperature control, you’re going to have to spend more money I’m afraid.

...unless someone has a better design?
 
Back
Top