Peltier Cooling Fermenter

[A3k]

Hi guys,

Im about to move into a unit and wont have space for a dedicated fermentation fridge so want to make a temperature controlled fermenter using Peltier devices. Id like to cut a hole in the side of a plastic fermenter for the device and silicone it in place, however Im not sure if this is a stupid idea as it could make a good place for bacteria.

Pelter devices on ebay seem pretty cheap.

If I just placed it on the side without a hole, the heat transfer would be pretty poor.

Has anyone done this before, what are peoples thoughts on sanitation with the silicone, and does anyone have any tips.

Thanks heaps
Al

 

[JasonY]

Check Doc's blog under the blogs section, I know he is trying this at the moment.

 

[Quintrex]

I reckon for sanitations sake I'd try and come up with a peltier jacket cooler or something!

 

[b_thomas]

The dome fridges in Target are a pretty good buy. They're only small ie. they fit a 30L carboy (or 24bottles of red/white) perfectly. It might save you a lot of hassle to just go out and invest in one.

 

[A3k]

I might go check out Target then. Although, i might still try this peliter thing out of curiosity. If it doesn't work I'll try and find another way to use the peltier device. I was watching the young inventors once and someone made a stubby holder with a peltier device in the bottom to keep the beer colder. Maybe i could do something similar.

 

[newguy]

It will work, but I'd like to encourage you to not cut a hole in your fermenter; infections will be much more likely. The only thing to watch out for is that peltier coolers are inefficient as hell. Yes, they're cheap on ebay, but you'll use a proportionately much higher amount of electricity. This effect is compounded by the fact that you can't keep the chip inside of an insulated box unless you really get fancy. This is because the peltier chip produces a cool side and a hot side. If you throw the whole thing inside a box, the heat liberated from the hot side can't escape and will heat up the box and your beer.

It's actually cheaper to buy a dedicated fridge once all the costs are considered.

 

[mesa]

The only thing to watch out for is that peltier coolers are inefficient as hell.

I've got to agree on that score. I you are going to try to do peltier cooling you need:
a) Fantastic insulation on your fermenter so that it doesn't get any heat from the outside and the only heat produced is due to the yeasts metabolism.
B) Fantastic heat sinking on the hot side of the peltier. This means either a big heat sink (might be worth getting one of the ones from a PC shop that are heat pipe based rather than solid Al or Cu) or maybe water cooling on the hot side.

If it was me with no space I'd consider either the fridge at target, or an ice based solution. Either
a) air cooling with two compartments, one with air one with fermenter and a temperature controled fan to circulate air or
B) liquid cooling with a cooling loop running either through the wort (silicon tube maybe) or around the outside of the fermenter (copper?) which will have iced water pumped through it if the temperature in the wort rises too much. Still need good insulation on any of these solutions though. (I was seriously considering the liquid cooling through the wort with the ice water supply from my keg fridge before I got handed another fridge ;-))

 

[chovain]

Something I've been wanting to make for a long time is a peltier fermentation box. I know there are cheaper and better ways to do it, but you guys must be used to my views on these kind of projects by now .

My plan is to make it with a wooden frame, plywood faces, styro insulation. The top would have a some nice big peltiers in it, with chunky heatsinks, and fans to circulate air around the hot and cold sides. It'd have PC power supply/ies through FETs to power the modules, and an MCU to control the whole thing. I've got a tube of PIC18F4550s which I have nothing better for, so I'd also consider incorporating temperature logging via a USB uplink .

One day...

 

[mickoz]

I second Newguy. Peltier heat pumps just provide a temperature differential across 2 plates. Heat is removed from one plate making it cold and move to the other side making it hot. The difference in temp is pretty much a constant (may be varied a little depending on current applied). This means that unless you disperse the heat from the hot side using fans, liquid cooling or plain old radiant dispersion you are not going to get very cold on the cold side.

These things are also horribly inefficient and will chew through power like you won't believe. I recommend you look at a cheap fridge or freezer with a Fridgemate.

Mick

 

[turto77]

I was looking at using one of the wine fridges for fermentation control, are they any more effeciant than say a small fridge with a fridgemate?

 

[mika]

Too small. I wanted something cheap to run, so I bought a fridge that's big enough to fit a fermentor and a couple of starters next to it and thats it. BIG MISTAKE. Middle of summer, I'm restricted to one brew every 2-3wks...I don't know about you, but I can drain that keg inside a week if some friends come round. It'd be interesting to see the cost difference between running a small fridge and running a bigga mutha that can fit 2 fermentors (perhaps 3?) I doubt that it'd end up being that much. Even better again, go the chest freezer, cheaper to run and 4 fermentors should be no problem in most of those bad boys. Only thing I'm not a real fan of is lifting the fermentor in and out of those, but then maybe I need to HTFU !

 

[turto77]

good point mika, my main concern was my lack of space to put the thing, but i suppose and upright fridge only unit should be able to fit two fermenters in about the same floor area as a smaller one.

Does anyone know if the peltier cooled wine fridges are any cheaper to run than a normal fridge of about the same size

 

[roger mellie]

good point mika, my main concern was my lack of space to put the thing, but i suppose and upright fridge only unit should be able to fit two fermenters in about the same floor area as a smaller one.

Does anyone know if the peltier cooled wine fridges are any cheaper to run than a normal fridge of about the same size

Who makes Peltier cooled wine fridges?

My Bosch wine fridge still has a compressor. I thought the Liebeherr (sp) and Eurocave ones were 'proper' fridges.


RM

 

[turto77]

RM,
there are a heap on ebay, here is an example i found here