My Mini Fridge to Fermentation Chamber Build

[chumpsteak]

Have fermented 2 batches in the chamber now. The only time I had any issues was with getting the primaries down to ferm temps initially. Have had to bring them down to 66 from around 80 since my ground water is pretty warm due to summer. After transferring the wort to the primary and pitching I just stuck the primary in the 66 degree chamber to cool down. The next morning (12 hours) I put the temp probe on the new primary and it was sitting at 73 instead of 66 because fermentation had already started. The fridge then had to work pretty hard for the next hour to get the primary down to the correct temp. The only issue from the fridge working that hard is a lot of condensation on the roof of the fridge. I just wiped it off with a towel to get the bulk of the water, and the damprid did the rest. Once I get them down to ferm temp the chamber keeps them nice and stabile. Was almost 100 out today and the chamber was fine. Seems to be working great.

 

[SarahMatt]

Your fermentation chamber looks great!
We built (or tried to build) one last week as well. The fridge is working REALLY hard. I've noticed that the outside of the fridge itself gets really hot. Do you have this issue as well?? Should I be worried?
Any advice would be appreciated!
Thanks,
Sarah.

 

[chumpsteak]

The sides of my mini fridge get pretty hot when the compressors been running for 5 minutes or so. The compressor itself gets even hotter though. It's 100 degrees outside this week and close to that in my garage. I have the temp in the chamber set to 68 and have the fridge kicking on at 68.5 degrees. It's having to run about every 15 minutes for 5-10 minutes, so it's working pretty hard. It does cool down pretty good in between so I'm not too worried about it.

I've been trying to optimize my Love controller settings, but I'm not having much luck finding the answers to my questions. I'm just wondering if it's better for the fridge compressor to run more often for short bursts or run less often for longer durations?

Maybe I'm doing it wrong and I should have it kicking on at 68.2. Not sure, but it hasn't burned up yet so maybe it's doing ok. This is the hottest weather we've had this year, so if it makes it past the next couple of weeks it should be good to go.

 

[SarahMatt]

Thanks for your response and the advice. I'm in South Florida and it's been HOT! I don't mind the heat, but it makes fermentation a little difficult.
I've seen the garage get up to 90; its usually holding at about 85. I don't have anything in the chamber (I moved everything inside until the chamber is up and working). The ambient air inside has been at about 75 (quite a feat for a garage in Florida in August!!) and water is holding at about 62!!!
Fermentation can't be any worse than what college kids do to mini-fridges!!
Thanks again,
Sarah.

 

[Armen_Tamzarian]

This is too cool! I PM'd you with a question about this!

 

[chumpsteak]

Just wanted to post and say that I changed my diff temp from .5 to 1.0 on the Love controller. This is letting the temp swing 1 degree before turning the compressor back on. This is allowing the compressor to fully cool between cycles. I think this is a better method that will hopefully prolong the life of the compressor.

 

[chumpsteak]

Started using a small fountain pump and have been pumping ice water through the immersion chiller once we bring it down to 100 using the hose. This has helped us get a much better cold break and has also allowed us to get the wort down to 70 degrees or so depending on how much ice we have on hand. Once the wort is down to 70 or lower I pitch and then put the primaries in the ferm chamber. I usually set the chamber to 60 or so and put the probe on a bottle of beer to get it nice and cool in there. When I check in the morning the primary is usually fermenting and sitting around 65 or so. I then tape the probe to the side of the primary with a piece of foam insulation around it and then set the chamber to whatever temp I want to ferment at. Has been 64 or 65 for ales and has been working great. The beers are coming out so clean tasting. No funk, just great beer. Oh, it's been 100 outside here and 90 plus in my garage and the chamber is working great. The compressor gets hot as hell sometimes but it hasn't shut itself off yet and the chamber is always at my setpoint when I check it.

 

[chumpsteak]

Just want to update this thread and say that I have now successfully fermented about 20 batches in the chamber without a hitch. It's now winter here in Idaho and I'm able to easily maintain 60-70 degrees in the chamber using a MyHeat personal heater. The heater cycles every hour or so and never has to work very hard. This chamber is by far the best investment I've made in my brewing habit....err hobby.

 

[Soldevi]

I have a mini fridge and space about the same. Thing is i want to use it as a fridge to cool my kegs. If I made the space smaller do you think it'd get cold enough? Or even in the low 40's?

Have you tried to see how cool yours can get? It rarely gets to 80 around here.

 

[chumpsteak]

I haven't tried going below about 55. This time of year ambient in my garage is probably about 50 most days so I think this time of year I could probably get it to the low 40's or even high 30's with no problems. As for summer time though, my garage temp can get into the high 90's so the fridge has to work pretty hard just to stay at ale ferm temps.

I've thought about aging kegs in mine as there's usually plenty of room, but I think if I do I will just use CO2 to purge the O2 out and keep the kegs at around ferm temps or 65. From there it would just take a few days to force carb them when a spot opened in the keezer.

I build a 5 tap keezer a few months ago though, so having room for kegs in there isn't usually a problem.

 

[chumpsteak]

6 degrees outside this morning and the ferm chamber is holding a steady 68 degrees with no problems. My garage is pretty close to freezing but the little buddy heater is working great in the chamber.

Have run probably 300 gallons of beer through the ferm chamber now and have had zero problems. Set it and walk away. Still the best thing I've ever built.

 

[ThaBrewFather06]

Thanks for this post I just found it and I'm going to give it a try!!!!

 

[nickybhoy]

Excellent build bud, enjoying the fruits of your labour. Yeehaa!

 

[chumpsteak]

Happiness is 30 gallons of beer fermenting away under full temp control.

 

[m3n00b]

Happiness is 30 gallons of beer fermenting away under full temp control.

Hate to bump but this is awesome!!!!

 

[finsfan]

very awesome indeed! thanks for sharing i think i may be building one of these now haha

 

[bunt1828]

I just build my own chamber based off (read: stolen from) this design and it is working out great! Thanks for the inspiration and ideas...

I went with the STC-1000 for a controler. Also, I was limited in terms of space to the width of my closet, but I can still ferment 15 gallons no problem (plenty for me), plus I've got room for a 2L starter on a stir plate (which is controled via one of the switches on top of the box the controler is mounted to) and could maybe squeeze in one 5 gallon keg for aging if needed. I live in Houston so temperature control is a must, and this design works perfect for me. Thanks again for the idea!!

 

[chumpsteak]

Lookin good. My garage hit 98 last week with the heat wave and the chamber held 68 with no problems. Been going strong for about 2 years now in extreme cold and hot conditions.

 

[sikkingj]

Great build! I have a quick question, have you ever been able to maintain lagering temperature?

Thanks for sharing!

 

[TBaGZ]

I need to get on building one of these.... Right after I build my keezer (freezer was delivered today)!

 

[chumpsteak]

Great build! I have a quick question, have you ever been able to maintain lagering temperature?

Thanks for sharing!

I haven't done lagers yet but I've done several ales at 58 to 60 degrees. Haven't tried it in the heat of summer though, I think it would work but would make the fridge compressor work way too hard. I have another fridge in my garage that I cold crash and lager in and I can lager in kegs in my keezer if I have to also.

 

[JFK]

great thread thank you for sharing it. I may not sell my diy kegerator after I finish my keezer now... I may have to make something very similar to this.

 

[zrule]

Anyone seen a walk-in chamber for 20 gallon conical?

 

[Hayseed]

After reading this I found a minifridge on craigslist . Is there a wiring schematic stashed away somewhere for hooking up the minifans and outlet ?

Very cool build !

 

[chumpsteak]

I found a love controller wiring diagram here on HBT somewhere that shows how to wire the controller to the outlets so that there is a hot and cold side output. As for the computer fans I just wired them in parallel to a cell phone charger. The charge is 12V and 500mA. The higher the Amp rating the faster the fans will turn. Just depends on how much air you want to move.

Also, I should mention that the chamber is still going strong after over 2 years of continual use. No problems at all with the fridge or heater. Very happy with it.

 

[chumpsteak]

Just a little update to show the chamber is still chugging along with no issues.

 

[GenIke]

So can you achieve lager temps?

 

[chumpsteak]

I haven't made a lager yet, but I have fermented at 60 degrees multiple times. Should be able to do 50 no problem during all but the summer months. Of course, just getting the wort down to a pitchable temp in summer is a challenge.

 

[mdbrewer1]

It took me forever to figure out that the whole setup wasn't one big refrigerator. I couldn't figure out how why it was so long and why the door was positioned so strangely. Now that I've figured it out, I might have to do one in my basement.

The setup looks nice, but if I can't make mine look that nice, I might try putting some sliding doors the whole length of my work bench to cover the door and the brewing supplies. Probably not necessary given how messy the basement is in general, but I think it would look nice.

Thanks for sharing!

 

[chumpsteak]

I would suggest you spend the time and effort to make it look as nice and functional as possible. If you can line the inside with paneling or something somewhat water proof it will just make clean up that much easier if there is a blow out or spill and if you brew a lot there will be both. If you can do a good job mounting a door then it will function perfectly for a long time and you wont have to mess with it. Mine is still just as good as when it was new.

Good luck on your build.