My $60 Single Vessel Fermentation Chamber

HomeBrewTalk.com - Beer, Wine, Mead, & Cider Brewing Discussion Community.

Help Support Homebrew Talk:

I searched high and low for a good location within my house that could hold fermentation temperatures but due to large fluctuations throughout the day this just wasn't possible. I quickly began searching for small scale fermentation solutions. Many people build large chambers from chest freezers or dorm room refrigerators.
I don't have a truck to pick up a large freezer or refrigerator so they were automatically out of the search criteria. I also wanted to do everything on the cheap; I like to keep things simple and easy that way I can spend money on ingredients!
Parts list:
**Note: The three items from Amazon put me over the 35$ free shipping threshold. That's the only reason I ordered that specific electrical tape.
  • $1 - Light socket from Ikea and a 60w light bulb to put in it.
  • Free the box that your items from amazon came in
Things you should already have:
  • A screwdriver for the fridge and STC-1000
  • A knife for modifying the wiring.
Wiring the STC-1000:
All credit goes to Jonathan_Marino and his how-to on How to set up an STC-1000 for beginners post.
Follow his how-to minus the project box. I used the 5 extension cables for all the wiring. Remove the female end from one and the male ends from 2 and strip the cable out of the remaining 2. Utilize the electrical tape and designate a color for each type of contact point. Once completed I taped the bulk of the wiring directly to the underside of the STC-1000 and used the blue and red tape to mark the female inputs as cold and hot. You can just rest the STC-1000 on top of your fridge or somewhere else out of the way, but still accessible.

The fridge
HBT.com led me to the ideal size of a 4.4cu ft mini fridge that is big enough to hold a standard fermentation bucket and carboys. I quickly began monitoring craigslist for my area until I found a 4.4cu ft Sanyo 4310. This fridge is fairly neglected because of the freezer compartment that is also the cooling element. Many brewers look for fridges this size for kegerators and not necessarily fermentation control so many shun these types of fridges.
The seller said that the fridge was over cooling and had not need for it anymore. I was planning on utilizing a STC-1000 for temperature control anyway so I picked the fridge up for 20$. I removed all the interior shelving and the door panel and then screwed in the magnetic stripping to the door where the door panel was removed from. It doesn't seal perfectly but I view this as a positive. The residual cooling/heating won't linger too long in the chamber which could cause overshooting of target temperatures.

Heating element
Cut a hole large enough to mount your light socket in your amazon box and some ventilation holes so heat can escape. I took it a step further and added a computer fan and have it plugged in to an always on socket. The ignition point of cardboard is approximately 450F and the bulb itself can emit about 260F so you should have no worries about it catching fire. As a safety precaution just make sure the bulb isn't touching the sides of your box.

Finishing Touches
I ran all the wiring in to the door on the side that is hinged in. I had enough gap in the striping that I have no issues with it closing. I am currently just taping the temperature probe, with insulation, to my fermentation bucket but plan on getting a thermowell in order to get the most accurate reading of my fermenting beer.
I am currently fermenting an Oatmeal Cream Stout and this setup is working wonderfully!

Good tutorial, lightbulb in the cardboard box seems sketchy to me though. For those that would like to be a little more cautious, a small paint can from Home Depot/or Lowes works great to mount the bulb in, is cheap, and is not flammable.
I built a nearly identical unit using almost the exact same items! I highly recommend this approach for anybody interested in a fermentation chamber on the cheap. Your fridge seems ideal, mine however only has enough headspace for a 5 gallon carboy with a blowoff tube as opposed to an airlock on a 6.5, so make sure you measure (but you cant beat free, so I'm not complaining!). The only suggestion I would add would be to consider the paint can approach (or in my case, an empty 28oz tin can) for the light bulb housing. I'd still be nervous about the lighbulb/carboard combo, and the metal can makes for a pretty efficient heat source.
I knew I would get flack for the cardboard heater! A little tin can sound promising. You could easily pickup one from the grocery store and modify!
A coffee can would be perfect with the plastic top off. I only used a tin can because that's what I had lying around that would fit into the cramped quarters of my fermentation chamber. I never considered tinfoil around the light bulb itself before. In theory that sounds like it would be a great option as well!
I would think that the foil around the bulb would really cause it to overheat and lower it's expected life. I love my design because of the fan that's always providing circulation. It's really surprising how stable my temps are. I wish I had the ability to monitor it and see how many times it cycles in a day.
Monitor your temp with one of these - http://store.idevicesinc.com/igrillmini/
When you aren't fermenting you can make better BBQ to go along with your better beer...
I've built two of these using the STC-1000 controller for both. For heating I decided to go with a reptile heat mat. You can get them at most pet stores as well as amazon. This works great because they are thin and also have adhesive on one side. I just stuck mine to the inside of the door and have a nice radiant heat source that doesn't take up any space and is waterproof.
I purchased (2) of the 8"x18", 24W heaters from here http://www.thatpetplace.com/reptitherm-u-t-h-heaters?sc=19&category=1506.
You could also go a little smaller and stick it to the floor of the fridge and sit your fermenter on top of it
I had an old crock pot where the liner broke. I use that as a heat element. I use it on the "warm" setting. On the low or high setting it got so hot one day it kind of warped the plastic on my freezer. As in the internal temp was at or greater than 150F, the limit on my thermometer. But anyway, a cheapo crock pot works.
Thanks for all the input! Many ideas floating around if I ever want to upgrade from my possibly flammable solution.
Tin Can/Foil
Coffee Can
Crock Pot
Reptile Heat Mat
And we also had someone mention a could temperature monitor: http://store.idevicesinc.com/igrillmini/
Great write up. Now look into flashing that STC-1000 (if it's rev 1.0) and having ultimate control over fermentation.
Thanks goes out to alphaomega for the incredibly talented work done for the project!
nickmv: I've been keeping any eye on that thread! I just can't justify buying the arduino right now...
Great write up! For heat, I used a plain old fashioned heating pad. Works great, reaches desired temperature setting surprisingly fast.
Instead of wrapping the bulb with foil, line the inside of your cardboard box with it. I've done that in the past with great results as well.