Icebox style kegerator and fermentation chamber build

[laredo7mm]

I decided to make my own hinges after searching and not finding anything that I liked. Well, I liked quite a few of them, but I am not willing to spend $1000 for a vintage set of hardware or $1000 per door for some CNC machined recreations made out of brass.

I ordered some refrigerator latches that will hopefully work after I modify them to reduce the offset of the hook. It is made for about a 1.5" offset and my doors are at 3/8" offset. They are adjustable, so I should be able to cut/mill/drill to get the correct height. We will see.

Here are the hinges on the cabinet to get an idea of the scale:

And a close up. Basically just a steel plate bolted to an existing hinge. Cheap, quick, and functional, but not very elegant.

 

[laredo7mm]

Hinges made and doors hung. I like them better than the brass hardware and they shouldn't contrast so much once I get the cabinet stained/waxed.

Next up will be to get the side vents built for the fermentation chamber and floors permanently in so I can get to insulating.

 

[iijakii]

Beautiful build! Looking forward to seeing what the taps will be like.

 

[NickTheGreat]

Dang. Nice project to say the least!

I like your hinges. They look nice with the styling of the whole thing.

 

[AkBrew907]

New hinges are a nice touch, look a lot better than the brass ones originally

 

[laredo7mm]

Progress has been a bit slow lately. Insulating this thing took forever. IDK why but it was such a chore. But it is almost done. I started waxing the doors but still have to sand and wax the cabinet.

I had to learn some refrigeration repair since I managed to snap/crack the lines when trying to get the compressor and evaporator into position. She seems to be holding pressure, but I still need to get to the correct suction pressure. I think she is still a bit low on refrigerant.

I did a temperature test last night with a poorly sealed lower chamber. The doors were just propped or taped in place and I put in a cardboard divider in the bottom next to the compressor area. She went from 66° to 37° in 10 minutes and then down to 33° in another 5 minutes. So hopefully she will be able to do the job of cooling 5 or 6 kegs.

 

[AgBrew12]

This is awesome looking! Cannot wait to see the finished product!

 

[laredo7mm]

I think I got the compressor dialed in last night and I changed the evaporator plenum to only use one fan (110 CFM) instead of three and increased its volume. I am getting about 22° F out of the plenum (measured at the fan) at its coldest at 18ish psi suction pressure. From the charts I looked at the evaporator should be at 19° with suction pressure of 18psi with R-134a refrigerant so I am pretty close since I am not actually measuring the evaporator temp.

When I did the temp test last night, it took the chamber down from 68° F to 28° in about 10 minutes.

I guess now I need to start working on sanding and waxing the main cabinet. I can't say that I am looking forward to that.

 

[dcbarisax1]

Sub'd. That looks amazing! My wife might let me display that ferm chamber lol!

 

[laredo7mm]

Got her waxed and the hinges painted. Not sure I like the color, but it is what it is. It looks better in person than in the pictures.

Now I have to get the vents in for the ferm chamber and put the top shelf in and insulate it. Then wire up the controllers and get the latches modified, painted, and installed.

I'm hoping to have it done by Wednesday. I have two beers that will be ready for kegging by then.

 

[actech]

sub'd

 

[Phischy]

I have a question. On my cold room build, I'm building 2 fermentation chambers off to the side. I need to pull coolant or cold air from the main room, to the temp controlled chambers. BUT: I don't want the ferm chambers to be a total hot spot and kill the efficiency of my cold room. Idea #1 is to just move air through a tube via PC fan with some sort of flapper to prevent airflow when not in use.

Idea #2 is to have a 10gal glycol reservoir in the cold room with 2 pumps, one for each chamber. Then have a heat exhcanger in each fermentation chamber with PC fans on them, all controlled via 2 stage controllers.

But, I don't know anything about these heat exchangers. I can figure out everything else but finding the right sized exchanger. I don't need a compressor.

 

[laredo7mm]

I have a question. On my cold room build, I'm building 2 fermentation chambers off to the side. I need to pull coolant or cold air from the main room, to the temp controlled chambers. BUT: I don't want the ferm chambers to be a total hot spot and kill the efficiency of my cold room. Idea #1 is to just move air through a tube via PC fan with some sort of flapper to prevent airflow when not in use.

Idea #2 is to have a 10gal glycol reservoir in the cold room with 2 pumps, one for each chamber. Then have a heat exhcanger in each fermentation chamber with PC fans on them, all controlled via 2 stage controllers.

But, I don't know anything about these heat exchangers. I can figure out everything else but finding the right sized exchanger. I don't need a compressor.

I have been pondering along the same lines, except I decided to not go with the glycol/pump/radiator route.

I would think if you kept both the inlet and outlet from your cold room at the same level (as low as possible) and in your fermentation chambers keep them as high as possible, then you wouldn't have too much loss to natural convection currents.

I have rolled it over in my mind a few times and I am going to try and do that on my set up. Similar to what was done in the "The Mother of All Fermentation Chillers" from the Wort-O-Matic site except I will make both my cold air feed and my warm air return high in the fermentation chamber. So when the ferm chamber is not calling for cold, there shouldn't be too many loses to convection.

 

[Phischy]

I can't do that, I have a walk in cold room and my fermentation chambers are 50" high each.

Which is why I wanted a flapper of some sort to restrict airflow when fans aren't on.

Now instead of the radiator idea, I'm looking at this:

http://www.gotta-brew.com/products/conical-cooling-jacket.html

Same idea with a reservoir but with the jacket it should be more efficient.

 

[laredo7mm]

Here are a couple of pics that are a bit more accurate on how the cabinet looks in person. It has an aged rustic look to it. The buffed wax has a nice luster and depth to it. That is what is causing the glare in the photos.

Here are the vents. Each is 10.25 x 1 inch to match the area of the 92mm fans at 47 CFM each. The one on the left is the cold air feed to the fermentation chamber and the one on the right is the warm air return to the refrigerated portion of the cabinet.

Here is everything in place. New plenum on the evaporator with a single 110 CFM 120mm fan. Below that is the condensate tray that will drain to the compressor compartment. Hopefully any condensate will evaporate so I won't need to keep and eye on it. Tomorrow night will be probably be spent insulating the top and hopefully get started on modifying the latches.

 

[Phischy]

This is a crazy build. Mad props to you. What sort of R factor do you have for the keg storage area?

 

[laredo7mm]

This is a crazy build. Mad props to you. What sort of R factor do you have for the keg storage area?

I have 1.5 inches of insulation everywhere. It is two layers of 0.75" rigid foam that has matte on one side and reflective on the other. I installed it with the matte sides facing each other so there is reflective on the inside and outside of the insulation. Each 0.75" foam is supposed to be R5 so R10 total in the keg area and the fermentation area plus whatever the 0.75" pine adds which probably isn't much. Hopefully it is enough.

I'm not so worried about efficiency as I am about condensation. I have every seam taped with the foil HVAC tape to negate any leaks. I think I have used 1.5 rolls of it so far.

 

[Phischy]

Do you think a single fan will pull enough cold air from up high to cool the fermenters? I ask because I have the same design issue, trying to figure a way to cool from my coldroom without it crashing the cold room.

 

[laredo7mm]

Do you think a single fan will pull enough cold air from up high to cool the fermenters?...

I hope so.

The fans I used for the fermentation chamber are 115V 92mm fans. Not 12V DC computer fans. They seem to move the air well, but I don't know how well they will cool the upper chamber until I get it all up and running. I got the controllers wired and mounted last night so hopefully tonight I can get the latches installed and give it a test. I don't plan on doing any lagering as of yet so I should only need to get the upper chamber down to about 60° F. With an ambient room temp of 65 to 75° F, I don't think it should be an issue. But I may find out it isn't enough when I have the heat load of two or three 6 gallon batches fermenting away.

In my picture above showing the ferm chamber vents installed in the cabinet, the fan on the left is pulling cold air from the lower refrigerated section while the fan on the right is pushing warm air from the ferm chamber back down into the lower chamber.

 

[laredo7mm]

I got the latches on last night and everything sealed tight...I hope. Set 5 gallons of wheat beer and 5 gallons of cream ale in the fridge chamber and turned it on. Everything was still looking good this morning so hopefully all is OK.

Here is my rigged up control panel behind the compressor door. I didn't spend much time on this or the wiring as I am planing on moving to the Arduino based controls.

Room temp in the picture below is about 67° F and the fridge portion is holding 37° F and the upper chamber with nothing running is at about 58° F. Not too bad of a temp difference. Should be easy to maintain ale fermentation temps.

Next I need to get the 5 way CO2 manifold installed and plumbed. But I will probably build and install the drawer that will hold the faucets first. And the last thing will be to add a bit of crown molding at the top to dress her up a bit.

 

[NickTheGreat]

Yay! Will be curious to see the temps when you start fermenting in it

 

[laredo7mm]

Crown on, drawer built and installed, taps installed and plumbed. All that is left to do now is mount and install the 5 way CO2 manifold and ponder a drip tray. The girlfriend and I pulled the first pints from it about 1.5 hours ago. She had a cream ale and I had a wheat beer.

 

[BrooklynTom]

Looks great. Congratulations.

 

[NickTheGreat]

I like the hidden tap door. Looks great!!!

 

[laredo7mm]

Looks great. Congratulations.

I like the hidden tap door. Looks great!!!

Thanks, she turned out better than I expected.

The tap drawer is OK, but a bit wonky. I didn't end up with much room to be too creative, so it is another once of those, it is what it is type deals. I may add another piece of stained/waxed wood to it to hide the evaporator plenum, but other that that, I am kind of restricted on what I can do. Too many refrigeration pipes, capillary tubes, beer lines, fermentation chamber vents, and condensation trays in there getting in my way.

I just ordered some 90° tail pieces to replace my straight ones. Hopefully that will alleviate some of the congestion.

 

[martyjhuebs]

That thing is amazing... great craftsmanship. Im assuming that a drip tray is next? It would be awful to make that thing messy...

 

[laredo7mm]

That thing is amazing... great craftsmanship. Im assuming that a drip tray is next? It would be awful to make that thing messy...

I had great plans for one. Even designed it so i could print it out on the 3D printer, but I ran out of room.

I was going to have the drawer with the taps pass over the top of it so it would only be in the correct potion when the drawer was in its retracted position, but I couldn't make the drawer wide enough to span it.

The rag is in there after pouring the first two pints and it was my first time using "real" faucets so I made a bit of a mess. Up until now I have been using the plastic picnic taps. I bought Intertap stainless steel (no flow control) faucets for this project. I learned that if I let the faucets completely empty into the glass after closing them that I don't get any drips after that. So I might be able to get by with not using a drip try.

 

[laredo7mm]

I got the CO2 manifold installed and plumbed last night. I ended up putting the CO2 tank in the fermentation chamber and running the line through the floor into the refrigeration chamber. Makes getting to the bottle easier not to mention it is easier to see my pressures on the regulator.

I forgot to mention the other day that I made a plug that I can insert into the end of the hot air return vent in the refrigeration chamber. This stopped most of the cold air getting into the fermentation chamber. The fan from the evaporator plenum blows directly toward the end of the warm air return vent. Instead of having a 10° F difference from ambient, now it is at about 1° F. Plus the compressor now turns on every 40 minutes instead of every 30 minutes. It stays on for about 10 minutes at a time.

I started a 1 liter yeast starter last night with WY1335 in preparation for brewing another batch of Yooper's oatmeal stout. I put it in the fermentation chamber and set the controller to 70° F and removed the plug. At first the cooling cycle clicked on since it was 73° F. It didn't take long to reduce the temp and after that, with the plug out, the "residual cooling effect" took over and the controller now calls for heat to combat the chamber wanting to go to 64° F. At least I know everything works. I might try putting in a shroud to redirect that air from the evaporator fan from blowing directly at the hot air return vent. Might help the situation

Either today or tomorrow I will have a brew night and give the fermentation chamber a real test. I am a bit leery of insulating and taping the temperature probe to the side of the carboy since there is nothing limiting the high temp in the ferm chamber. If it calls for heat, it will heat until the wort is at temp. That could mean the ferm chamber temp is 100° F and then, if it calls for cooling, all that hot air will be blown into the refrigeration chamber. Not sure I like that idea. I will probably just keep the probe in free air and set the ferm temp to a few degrees below my wort fermentation temperature and monitor it from there. I have a fermometer on the carboy so I can adjust my ambient temp as needed. It just won't be a set it and forget it situation.

All the more reason to go to a PID set up. I am pretty sure I can set an upper limit for the fermentation chamber temperature.

 

[laredo7mm]

Hey all, I had a couple requests for an update on how she has been working out so I thought I would post it here.

The cabinet has been running for about three months with only one issue. I installed a BrewPi system not too long after my last post and I had one of the mechanical relays that runs the compressor stick in the on position (after about two months of running). I switched it over to different mechanical relay and then ordered and subsequently installed a 25A SSR and heat sink.

I have brewed 3 or four times since it was completed and the fermentation chamber works great. One of the batches was a double batch of "Cream of Three Crops" and the chamber had no issues keeping both carboys at the set temp.

I have five kegs in the refrigerated lower part and have the BrewPi set to fridge constant at 39°. With the house at 74° the compressor runs for about 12 minutes and then is off for about 55 minutes. I measured 7 amps on compressor start up and then it settles down to about 3.25 amps. Should cost about $10 a month to operate.