Insulated Fermenter

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Ross

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A guy I gave a mash demo to the other day has had the idea of fermenting in insulated 30L eskys with a S/S coil inside each one, which he can pump cold water through (& possibly hot if needed) to control the ferment temperatures. His reason for doing this, is he can keep one reservoir of say 50L at 1c in a fridge, but be able to brew at different ale & lager temps & possible handle lagering as well, all with one fridge...

Sounds like a great idea to me - Any one doing it already? Can you see any pifalls?

Cheers....
 
i was thinking about this earlier as well rather than sitting the fermentor in a water bath to lower temps as i dont have a fermenting fridge
 
Sounds like a mini-version the attemperator coils in the fermentors at at the Gibbs Mew brewery. A bugger to clean, but I can't see why else it wouldn't work.

I don't know if you'd get a good seal around the lid & airlock, but that wouldn't matter for an ale at least.
 
The thought had crossed my mind but since I picked up my new fridge it has gone to the back burner!

I was going to go for a copper tank (good heat transfer) in the freezer compartment of a small two door cyclic defrost fridge filled with propylene glycol which would be circulated to a stainless coil in the fermenter. I planned to use a pond pump in the tank and to insulate the fermenter with Aeroflex sheet insulation.

Maybe it will happen one day
 
Slugger is a legend sounds a great Idea to me. Pumpy
 
I had a similar idea after watching the Monster Garage Fire truck Brewery episode. never got around to doing it, but have a small car oil cooler that i was going to sit in the freezer, and pump glycol though out of a resevior, then through a coil in the fermentor. A simple temp sensor could switch the pump on and off.
 
jgriffin said:
I had a similar idea after watching the Monster Garage Fire truck Brewery episode. never got around to doing it, but have a small car oil cooler that i was going to sit in the freezer, and pump glycol though out of a resevior, then through a coil in the fermentor. A simple temp sensor could switch the pump on and off.
[post="59426"][/post]​

The oil cooler would not really have enough thermal mass to work well as we are talking about a secondary refrigeration process. The refrigeration system in the freezer is cooling the walls of the freezer (primary refrigeration) so you need to maximise the surface contact of the glycol your secondary refrigerant with the freezer interior. A large amount of stored glycol will also give your system some holdover capacity (ie cooling when the fridge is not running)

I remember that when I had my fridge set for lager fermenting (~12 C) that the fridge was not running long enough to maintain the freezer section much below zero.

Also make sure you use propylene glycol in your system if there is a chnace you could get cross contamination with your beer (glycol hose splitting and dumping into the fermenter etc) it is food safe. Ethylene glycol is cheaper but not food safe.

Cheers Ausdb :)
 
For the cost of the stainless coils, the pumps/hosing/connections/insulation for hoses, the thermostats, the eskies and the other crap needed to run it and the space, you would honestly be better off buying another fridge or two. For ales make a box that you can put a thermostatically controlled light bulb in or put the light in the fridge when it's turned off if you need to keep an ale warm. Then just turn the fridges off when you are not using them to save power. My two fridges cost me $30 and $25, and while the $25 one is not particularly pretty (it is a bar fridge that holds a 30L fermenter perfectly) my $30 fridge is in perfect condition and looks great. I use this one as my kegging fridge and have my taps mounted through the door.

Fridges aren't dear if you look around. Ask enough people and I bet you would score one for nothing. Plenty of people upgrade their fridges but dont have the means or bothered to dispose of the old one. There is many a garage with an unused fridge sitting in it.

Cheers, Justin
 
Ross,
There is a bloke in Brisbane with such a setup. He gave a talk about it at a Babbs meeting last year. From memory his was conical stainless steel with 100lt capacity. He used to do 80lt batches. It had coils running around the inner walls of the fermenter and he would pump a cooling solution through the coils. I cannot recall his name at the moment but I will try and dig out some of the babbs newsletters to find out.

:beer:
Anthony
 
Justin said:
For the cost of the stainless coils, the pumps/hosing/connections/insulation for hoses, the thermostats, the eskies and the other crap needed to run it and the space, you would honestly be better off buying another fridge or two. For ales make a box that you can put a thermostatically controlled light bulb in or put the light in the fridge when it's turned off if you need to keep an ale warm. Then just turn the fridges off when you are not using them to save power. My two fridges cost me $30 and $25, and while the $25 one is not particularly pretty (it is a bar fridge that holds a 30L fermenter perfectly) my $30 fridge is in perfect condition and looks great. I use this one as my kegging fridge and have my taps mounted through the door.

Fridges aren't dear if you look around. Ask enough people and I bet you would score one for nothing. Plenty of people upgrade their fridges but dont have the means or bothered to dispose of the old one. There is many a garage with an unused fridge sitting in it.

Cheers, Justin
[post="59461"][/post]​

Justin,

Exactly what I do, I have 3 but could do with 4 - but running old several old fridges can be a huge cost on your electric - a mate of mine got an old beer fridge that put hundreds on his quarterly electric bill, so ended up dumping it. Also you need to have the space for them - The question was raised for any unforseen problems...
 
Sounds like a great big pain in the arse to me, but good luck to whoever goes down this path. :)
 
Couldn't resist showing off my latest toy...

fermfrig.jpg

It's a commercial fridge, bought from Arthur (via eBay) for $250.

I have installed my 2-stage controller, at the moment it just has an old convection heater in it but I will replace it with something neater. It will easily hold 4 fermenters / glass carboys etc and if I want, 12 (yes 12) cornies for lagering!

It has a constantly running fan which is probably ideal for fermenting, better heat transfer with the fermenters and less stratification.

Oh yeah, and I've added some red LED spotlights so it lights up nicely at night :super:

Now I just need a nice shiney stainless conical to go in it...
 
So after all additions wortgames, how much did the whole thing set you back, and does it cost much to run? I have to tell you it looks absolutely great.
 
Thanks LL. The 2-stage controller ended up costing over $200 - long story, explained here (post #14): http://www.aussiehomebrewer.com/forum/Wort...uff-t4875.html#. You can get them cheaper, but I have had trouble with grossly innacurate ones so I'm reluctant to take the chance on eBay to save $50 or so.

Basically that's it - the fridge and the controller (I added a couple of override switches so say another $10 at Jaycar). I will add some sort of ceramic heater element and a second probe that can be immersed in a fermenter so maybe another $50 in the future. The LED spotlights are Jaycar ones I had left over from another project.

It probably won't be the cheapest thing to run, there is a fan which runs constantly and from what I can tell, the fan and the controller seem to add about 5 or 6 degrees to the internal temp which will have to be chilled back out in the summer (at least it suggests the insulation is good). However, the convenience of having a perfect fermenting environment will be worth it - and when I do get a conical it will look soooo cool...

fermfrig2.jpg
 
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