Cannot Keep Ferm Temps Down In Cabinet

So I turned a small cabinet I found in the basement into a fermentation cabinet by lining the inside with some insulating sheathing, sticking a lightbulb in a paintcan for the heater, and a couple fans to try to keep the box cool.

I have one fan pulling air from the outside into the box over a tray full of water with some sponges for the air to blow through and hopefully act as a small evaporative cooler... Unfortunately I have been running it and I haven't been able to get the temps to go below 70 degrees during fermentation

The basement is pretty cool, usually 60-65 degrees, so I figured a mini swamp cooler would be enough, but I was wrong. I've only been doing 1 and 3 gallon batches, so that might work in my favor as there will not be as much heat.

Also, I am waiting for my eBay temperature controller to come in the mail so I can maintain temps with that, so I need some sort of cooler that can turn off and on if possible.

Does anybody have a good idea for me? I have seen some folks take apart mini fridges and use the compressor and such to cool a box, but I don't know how that all would work. I kind of would like to make this cabinet work, as I've already put a bunch of work into it. I'm trying to keep it pretty low budget and not too complex if I can help it.

Thanks everybody. Links to similar builds, new ideas, and the like are all helpful.

Here is what I'm working with

I'm far from an expert, but it looks like you need more cooling capacity. The fan/wet sponge is probably not up to the heat generated by fermentation.

You might be better off out in the open, your insulation may actually be holding heat in.

RazzBarlow said:

I'm far from an expert, but it looks like you need more cooling capacity. The fan/wet sponge is probably not up to the heat generated by fermentation.

You might be better off out in the open, your insulation may actually be holding heat in.

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I'm thinking about getting a tiny fridge and taking it apart and using only the cooling components in my cabinet... Something similar to this.
http://denver.craigslist.org/for/2918427818.html

I don't know anything about using fridge components, but I can probably figure it out...?

It's pretty simple to do what you're suggesting, and a lot of guys do it that way.

RazzBarlow said:

It's pretty simple to do what you're suggesting, and a lot of guys do it that way.

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I'm on the hunt for a mini fridge to Frankenstein...

for the short term, you can find a tub that will hold that fermenting bucket and fit into your cabinet - fill with water and a few frozen water bottles. The insulation will minimize the number of times you have to change out the bottles - maybe once in the morning, once in the evening -

I've always been partial to the small window AC vs. mini fridge internals. It's a little more bulky, but it has much more cooling power and it already has the fan integrated into it.

JKoravos said:

I've always been partial to the small window AC vs. mini fridge internals. It's a little more bulky, but it has much more cooling power and it already has the fan integrated into it.

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Yeah, I looked into those too, but just from looking it seems like taking out the compressor and condenser and such out of the fridge would be a little more space-efficient. I'm trying to keep this cabinet pretty small so it will still fit in that spot I have it.

Thanks for the suggestions, guys! Fermentation has slowed, so the beer is too cold now... Luckily I have no problem heating it!

Mini fridge is the way to go. Until you get one you can always stick frozen water bottles in there and have the fan blowing onto them circulating cold air. I did this for a while and would swap 2 bottles when I went to work and when I got home from work. After a while its a pain but it def works.

I think I may have found a mini fridge to dismantle and attach to the box... Anybody have some advice on this? Or is is pretty straight forward as far as the coils and the compressor go?

BoxBrewer said:

I think I may have found a mini fridge to dismantle and attach to the box... Anybody have some advice on this? Or is is pretty straight forward as far as the coils and the compressor go?

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I've never played with refrigeration but be very careful, if you crack or puncture a coolant line you are finished. It would cost more to repair that start over with a new fridge.

Added: I have seen a lot of builds where they just take the door off the mini fridge and incorporate the entire unit in one end of the chamber. This is what I plan when I get around to making a chamber. That is, if I don't go with the temperature controlled chest freezer. I like the idea of a side accessed chamber though so I wouldn't have to lift the fermenter over the side of the freezer.

Couple of questions that struck me...
What kind of beer are you making to decide what temp your trying to maintain? If its an Ale, your already seeing "60-65" degree temps in your basement so why not just leave it in the basement (assuming that ambient temp is 24hrs/day.

A couple people, and yourself, have already hit up probably the best solution (well 2 solutions). 1) For the time being use frozen 2 litre bottles to cool the chamber off. Problem with this is you never will be able to acheive full control of the temps. As it may be colder then you want at some point (although highly unlikely) especially if you dump the temp controller in there wired to the heater. 2) Dismantle a small dorm fridge. Its super easy as all your doing is removing the condensor, lines, wireing and cooling plate. Just take a picture of what it looks like before and mimic that same picture during install.

If your going the route of using, said dorm fridge (mimi fridge), and want to remove the door that will work, especially for that small of a space. Hopefully your temp controller you ordered is multi phase so it can control the cooling and heating as needed. I use a mini fridge (Magic Chef - one size up from mini) on my build and it works perfectly. See here https://www.homebrewtalk.com/f51/ferm-build-progress-pics-tons-pics-312828/

Hope it all works out. When in doubt, breeze through the 100's of posts here as people have done some pretty awesome builds as well as pretty simplistic to acheive their utlitmate goal. Your in good hands on this forum.

buckley28 said:

If its an Ale, your already seeing "60-65" degree temps in your basement so why not just leave it in the basement (assuming that ambient temp is 24hrs/day.

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Just a word of caution here - The thermal activity of the yeast in the first 3-5 days of fermentation is incredible. I have measured 10F above ambient. One member posted 16F above ambient. Ambient is good when things slow down, but you're fermenting at 75F or more during the early phase. This is fine if that's the range your yeast like, but most ale yeasts are listed as best from 60-68F, not 75-80F

Yeah, even in the 60 degree basement the fermenter was still at 70 degrees during the initial fermentation.

I found a free mini fridge so I'm gonna go pick it up and see what I can do with it. I am hoping to take out the parts so I can keep the cabinet small, but I might have to attach it to the cabinet directly like some folks on here do.

+1 on the frozen bottles for now especially the first few days of aggressive fermentation, the KISS method.

Unless your cabinet will hold more than one carboy, it would be much easier to just leave the fridge intact and attach to the temp controller to it rather than taking it apart and jerry rigging its compressor to the cabinet.

JonK331 said:

Unless your cabinet will hold more than one carboy, it would be much easier to just leave the fridge intact and attach to the temp controller to it rather than taking it apart and jerry rigging its compressor to the cabinet.

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Yeah, I think you may be right... I am going to pick up the fridge and see how easy it would be to get the compressor out compared to another method...

I may end up cutting open an entire section of the cabinet and attaching the doorless fridge to it. We shall see... I'll post up what I end up deciding to do. The biggest issue is space right now, so I am trying to keep it pretty small if possible...

BoxBrewer said:

Yeah, I think you may be right... I am going to pick up the fridge and see how easy it would be to get the compressor out compared to another method...

I may end up cutting open an entire section of the cabinet and attaching the doorless fridge to it. We shall see... I'll post up what I end up deciding to do. The biggest issue is space right now, so I am trying to keep it pretty small if possible...

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The best possible solution for a mini fridge like that would to be cut a hole in the bottom and place a fan over the hole to blow cold air into the cabinet. Place a controller on the unit and the thermostat in the cabinet. Or that's how I would do it.

So this is the fridge I just picked up.... FOR FREE Keep in mind that I am really trying to minimize used space.... I do like the idea of hooking up the fridge via a fan/duct into my cabinet, but I would need twice as much space for the cabinet AND the fridge.





Right now I am thinking about using this fridge as a fermentation cabinet, and saving my other cabinet for another day... As sad as that is. I can fit my 3 gallon carboy in this fridge and I could put my heater in it and run my thermostat to the fridge and heater. Let me know if you guys have some ideas. I don't really want to tear this fridge apart.

I say tear it apart. Its free. Can always pick one up for cheap on craigslist.

mjmac85 said:

I say tear it apart. Its free. Can always pick one up for cheap on craigslist.

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I don't know if I can, honestly. The coils go all around the sides of the fridge. I actually tried to take that back panel off and I think it's really glued in there...

So I think I am going to use the fridge as my "primary fermenter" and the other cabinet I made as a "secondary" haha. I have problems keeping the beer warm enough in my basement once the fermentation has slowed down, so I think this will work out. The cabinet will only have a heater wired up to another thermostat.

Here is the fridge equipped with it's own heater and fan.