Fermentation Chamber Stats

[DrDarwin]

I'm in the middle of fabricating a fermentation chamber (I'll post build pics later), and I was wondering what kinds of temps people have been able to hold with different systems. I'm particularly interested in the performance of smaller mini-fridge based systems, but feel free to post anything you've got.

I'm basing my system on a 2.4 cu ft Sanyo mini-fridge I have laying around, and the final product should be near 18.5 total cubic footage internally (~3' x 2.25' x 2.5' + the 2.4 cu ft fridge). With any luck I'll be able to maintain lager temps (should have near 18 R conservatively on all sides), but I wanted to see what kinds of performance other members here have been seeing.

 

[Tinga]

Interested as well. I'm making a fermentation chamber my next project.

 

[bmeyer46]

same here, but without fridge

 

[kickrjason]

Make sure your fridge can handle it! i just built a ferm chamber out of a fridge and the compressor must Barely be able to keep the stock fridge airspace cold. once i built it into a ferm chamber it is struggling to hold 68* internally. The ferm chamber is VERY well insulated so i know its not leaking air anywhere. However the exterior of the fridge where the cooling coils are had reached 145* at times. i have to have a fan blowing on it constantly just to keep it from shutting off. I am ripping the fridge out this weekend and putting in a window A/C unit. at least as a bonus i will gain more cubic inches with the swap.

 

[dutchoven]

I use an upright freezer and love it ... ferm temps to cold crash with a few clicks on the temp controller. I appreciate the DIY aspect of building a fermentation chamber from a mini fridge, but would recommend using a freezer. For those of you who built a chamber from a mini fridge, what was your total cost? For me, I pieced together a complete system using a freezer for around $200 ... as a bonus it pulls just over a kilowatt hour per week (sitting in a hot garage).

Here's my build: https://www.homebrewtalk.com/f51/dutch-s-cadillac-fermentation-chamber-build-251579/

 

[DrDarwin]

Make sure your fridge can handle it! i just built a ferm chamber out of a fridge and the compressor must Barely be able to keep the stock fridge airspace cold. once i built it into a ferm chamber it is struggling to hold 68* internally. The ferm chamber is VERY well insulated so i know its not leaking air anywhere. However the exterior of the fridge where the cooling coils are had reached 145* at times. i have to have a fan blowing on it constantly just to keep it from shutting off. I am ripping the fridge out this weekend and putting in a window A/C unit. at least as a bonus i will gain more cubic inches with the swap.

That's part of why I posted this thread. I was hoping to hear about the successes and failures people have actually experienced with this kind of build (and others).

I believe I saw in another thread that many of the mini to counter height fridges use the same, or very similar, compressors. Regardless, based on my conservative calculations my chamber should only require around 100-125 BTUs to cool to 40F in 80F ambient temps. Everything I've found indicates that my mini-fridge should be capable of ~150 BTU. I'm also planning on using dry ice or other cold thermal mass to cool the chamber initially. With luck, my insulation will help reduce the work the fridge actually needs to do to maintain the chamber temps to something reasonable. I'm hoping the initial chill will prevent the compressor from being overworked from the get go.

I use an upright freezer and love it ... ferm temps to cold crash with a few clicks on the temp controller. I appreciate the DIY aspect of building a fermentation chamber from a mini fridge, but would recommend using a freezer. For those of you who built a chamber from a mini fridge, what was your total cost? For me, I pieced together a complete system using a freezer for around $200 ... as a bonus it pulls just over a kilowatt hour per week (sitting in a hot garage).

Here's my build: https://www.homebrewtalk.com/f51/dutch-s-cadillac-fermentation-chamber-build-251579/

If I could have gotten away with another upright freezer purchase for my beer brewing addiction, I think I would have liked to have gone that way with my ferm chamber project. For now though, that's not in the cards. I'm also highly space constrained, so my build is a table/fermentation chamber combo. The whole chamber has to fit through a small doorway as well (~30in at its smallest), so a large upright freezer like yours would probably not fit. What are its base dimensions? I had to get a little creative with my woodcutting and sealing jobs.

I was able to piece my project together for a little over $200, but I had a few parts already laying around. I also modeled the whole build in CATIA, so I knew exactly what I needed from a materials standpoint. The bulk of my cost, by a long shot, was the insulation. I purchased five 4x8 sheets of .75," R5 RMAX insulation, and another two 4x8 sheets of .5," R3.2 RMAX insulation. At over $10 a pop, those added up quick.

 

[Ace_Club]

Make sure your fridge can handle it! i just built a ferm chamber out of a fridge and the compressor must Barely be able to keep the stock fridge airspace cold. once i built it into a ferm chamber it is struggling to hold 68* internally. The ferm chamber is VERY well insulated so i know its not leaking air anywhere. However the exterior of the fridge where the cooling coils are had reached 145* at times. i have to have a fan blowing on it constantly just to keep it from shutting off. I am ripping the fridge out this weekend and putting in a window A/C unit. at least as a bonus i will gain more cubic inches with the swap.

Are you sure the fridge was working properly to begin with? That size fridge should be able to handle your chamber space no problem. Hell, people have posted builds with a 1.8 cu. ft. fridge cooling off that much space. Something is not adding up with your build.

 

[kickrjason]

Well it was plugged in for days before the build began. Ran fine on max cold setting, outside was slightly warm (90ish).

I have two pc fans on the front of the freezer shelf circulating air.

I did get the fridge off of craigslist. So no telling if it was a legit sale or if I bought a junk fridge.

Sent from my iPhone using HB Talk

 

[bmeyer46]

make sure there isn't a ton of gunk on the coils or condensor, and that the fan is running to cool it off. I had a problem with my fridge getting pretty damn warm on the sides of it, so we pulled it out, and a mouse had gotten caught in the fan and it wasn't turning at all. ( that sounded gross, but it was in a shed outside, and we had feed in there also)

 

[kickrjason]

That's the problem with this design. The coils are under the metal skin of the sides of the fridge. That is why I was saying it was only designed to cool the cubic inches of the original fridge. The thermal exchange of the skin of the fridge is very inefficient. So the sides have reached 145* so far.

Sent from my iPhone using HB Talk