jco3rd
Member
Hey everyone. Thought I would add to the knowledge base a bit here. I was originally inspired by the classic posts on HBT that showed this type of build as a fermentation chamber/keezer combo; here, here, and here. My goal was to have a fridge temp side on the former freezer side for bottle storage and a kitchen fridge annex on the freezer side, and a single zone fermentation chamber on the fridge side. My build is a bit simpler than the examples above because I'm not trying to fit kegs into the freezer side. So I thin kit fits more into the Fermenter DIY.
My original vision was to control each side of the unit by a separate STC-1000, and have a shelf of some kind in the fridge side so I could fit two carboys in, because I generally brew two batches on a brew day. Plus it would just be wasted space otherwise. .
I picked up a GE side by side fridge from approximately 1997 for free on craig's list and got to work. I pulled out all the shelves on the fridge side, and I also removed the shelves on the door on the fridge side. A lot of the other builds talk about having to use a dremel to remove the plastic shelves, but fortunately no such shennanigans were required on this fridge. The screws that held the door seal on also secured the plastic fridge shelves to the door as well.
You can see that there are mostly notches on the shelves, so I was able to simply loosen the vast majority of the screws, and flex the plastic shelves to get it out. I didn't even have to completely remove the door seal which was great. Then I was able to tighten down all the screws to secure the seal back to the door.
For funsies I also cut out the holes in the door for mounting the STC-1000s. I drilled a hole, and used a metal blade in a jig saw to cut out the metal and foam.
It was at this point I discovered one of the main design differences between the GE fridge I was working with and the Kenmores that some of the other guys used is that mine only had one analog thermostat instead of two. Basically the fridge side analog temp control controlled the compressor, and the temperature of the freezer was controlled by a manual baffle system. If you wanted your freezer warmer, you would move the lever, and the baffle between the freezer and fridge would open up. If you wanted it colder, you would close it. In between was your adjustment area. This was very different so I spent some time googling the issue to figure out how the hell I would put two temperature controllers in the place of one and how that circuit would look.
It was as a result of that search that I stumbled across two builds that dealt with a single analog temperature controller. These builds also had a major design difference from the original posts I was modelling my build off of. The fridge side was split into two separate zones and each could be independently temperature controlled. Well this sounded pretty appealing and so my project suffered from some significant mission creep. A friend had given me a Ranco temperature controller, which I would use for the freezer side temp. The two STC-1000s (upgraded now to Rainbird ITC-1000s) would each control a separate fan. The fans would blow cold air from the freezer into their respective chambers. I bought two AC fans that were roughly 5x5, and two louvered dryer vents because I planned to add a heating element to the chambers at some point in the future.
I cut off the dryer vent lip on the back of the vents
I then placed each fan over the dryer vent and drilled holes through for the mounting screws
Particularly tricky was the fact that one of the screws of the fan interacted with one of the three louvers for the vent. So some creative enlarging of the hole was required to make sure the vent was able to swing open freely. But eventually it worked.
Then I tackled cutting holes for the fans in the wall between the fridge and freezer. This was a gigantic chore. I made sure to start with existing holes in the wall from the air supply and return from the old fridge side setup. I borrowed a dremel from a friend, and got to work. It was a lot harder than I expected. The wall between the fridge and freezer was steel. It wasn't so hard cutting out the first part on the fridge side, but cutting out the size of the fans on the freezer side was a nightmare. There were components to protect and also it is VERY close quarters on the freezer side, so it was hard to fit me and the dremel in there with enough room to move my arms enough to make the fine motions necessary for good clean cuts. Eventually I succeeded.
Another lesson I learned was to make sure there was adequate clearance for all the wires that needed to go from the freezer side to the fridge side. The wiring I dealt with basically came into the unit on the fridge side, moved over to the freezer side at the bottom, and then came back in to the fridge side at the top. Plus I had to run the fan wires back into the fridge side to hook up to the temperature controllers in the door. The top fan had a convenient hole right below the main hole I was using and I was able to simply thread the fan's wire through that.
The bottom one took a bit more wrangling with the dremel until I got it in right. This was due to the wires in that location.
I spent a good deal of time measuring and planning at this point. The goal was to fit as many carboys in both chambers as possible. My largest carboys are glass and encased in a wooden frame to avoid breakage, so I wanted to make sure these would be able to fit, with airlock, in each chamber.
(Not my cold room unfortunately!!)
The back of my fridge side had a bit of a hump to it, so I also wanted to make sure I could build a little shelf back there and fit at least a better bottle with an airlock back there. So it took a bit to get it right, but ultimately the shelf between the two chambers roughly split the difference. Since I wanted maximum space inside, I figured all I would need to do was insulate the front and top of the bottom chamber to insulate the two sides from each other. Once i got the measurements set, I got a sheet of 1/2 inch plywood, and a sheet of R6 hard foam insulation. I also got a roll of soft foam weatherstripping, two hinges, and two sliding latches. My design was to screw four legs into the 1/2 inch plywood shelf. These would rest on the bottom of the fridge side. The rear of the shelf would rest on and be secured to two cleats that were mounted to the fridge with screws. The middle legs had a cleat mounted on them which supported the shelf that went from the hump to the cleat to provide a level surface for another carboy in the lower chamber. I already had a bunch of 1x4 material leftover from my carboy cage projects, so I used those for the legs and the cleats. I built a bit of a door frame with the front legs. Once I did a couple dry fits and had everything where I wanted it, I installed the cabinet.
Now it was time to tackle my least favorite part of the build, the electrical. One thing I figured out pretty quickly is that I would have to wire the lower Inkbird first, and then the upper one, because the screws to secure the wires are on top of the unit.
I used 14/3 Romex for most of my wiring but this was ridiculous overkill as the fans did not have a ground wire. Probably when I use a heating element it will but I will cross that bridge when I get to it. Plus, the solid core 14 gauge wire is RIDICULOUSLY unflexible. using it to mount to something like a door that is on hinges was difficult. Based on the number I used to strip wire in the fridge, I would guess that braided 16 gauge is plenty stiff enough. Just make sure you keep track of hot and neutral and you will be fine.
I noticed that both of the dual chamber builds I had seen before had run a separate AC line to the fridge to power the fermentation chamber side. I didn't really understand that at first, and my initial thought was that I would have the Ranco control the freezer side, and then just tap into the electrical harness on the fridge side to get power to my Inkbirds and the fans. This was a bad idea for two reasons.
The first reason why that is a bad idea is the fermentation chambers should be able to draw cold air or turn on the heater in the fermentation chamber side when the ranco has the compressor turned off.
The second reason is that I couldn't get the compressor to operate properly when I tried to pull power for the Inkbirds from the wiring harness.
For those two reasons, I went to Home Depot and bought a $3 two prong extension cord. I was able to run it through the bottom of my fermentation side through where a water line had come through, and then hook it up to the inkbirds, etc., that way. Everything worked great then. Ranco can have the compressor shut off, but the fans can keep blowing.
I was able to drop the temp on the fermentation side from around 79 to 50 overnight.
I'm still fiddling with temperature control and I expect that to be a work in progress. I actually removed some of the louvers this morning because i was unable to get the chambers to drop below 50. The fans do not blow as aggressively as you might think, the louvers don't really open that much, so when you are trying to get it colder it may be necessary to remove them to get the temps down. I will check back tonight and report.
That's pretty much it! Thanks for checking out my thread and thanks to the legions of handy HBT-ers who went on before to give me the inspiration to tackle this project. Feel free to ask me any questions below, happy to provide any insight I can.
My original vision was to control each side of the unit by a separate STC-1000, and have a shelf of some kind in the fridge side so I could fit two carboys in, because I generally brew two batches on a brew day. Plus it would just be wasted space otherwise. .
I picked up a GE side by side fridge from approximately 1997 for free on craig's list and got to work. I pulled out all the shelves on the fridge side, and I also removed the shelves on the door on the fridge side. A lot of the other builds talk about having to use a dremel to remove the plastic shelves, but fortunately no such shennanigans were required on this fridge. The screws that held the door seal on also secured the plastic fridge shelves to the door as well.
You can see that there are mostly notches on the shelves, so I was able to simply loosen the vast majority of the screws, and flex the plastic shelves to get it out. I didn't even have to completely remove the door seal which was great. Then I was able to tighten down all the screws to secure the seal back to the door.
For funsies I also cut out the holes in the door for mounting the STC-1000s. I drilled a hole, and used a metal blade in a jig saw to cut out the metal and foam.
It was at this point I discovered one of the main design differences between the GE fridge I was working with and the Kenmores that some of the other guys used is that mine only had one analog thermostat instead of two. Basically the fridge side analog temp control controlled the compressor, and the temperature of the freezer was controlled by a manual baffle system. If you wanted your freezer warmer, you would move the lever, and the baffle between the freezer and fridge would open up. If you wanted it colder, you would close it. In between was your adjustment area. This was very different so I spent some time googling the issue to figure out how the hell I would put two temperature controllers in the place of one and how that circuit would look.
It was as a result of that search that I stumbled across two builds that dealt with a single analog temperature controller. These builds also had a major design difference from the original posts I was modelling my build off of. The fridge side was split into two separate zones and each could be independently temperature controlled. Well this sounded pretty appealing and so my project suffered from some significant mission creep. A friend had given me a Ranco temperature controller, which I would use for the freezer side temp. The two STC-1000s (upgraded now to Rainbird ITC-1000s) would each control a separate fan. The fans would blow cold air from the freezer into their respective chambers. I bought two AC fans that were roughly 5x5, and two louvered dryer vents because I planned to add a heating element to the chambers at some point in the future.
I cut off the dryer vent lip on the back of the vents
I then placed each fan over the dryer vent and drilled holes through for the mounting screws
Particularly tricky was the fact that one of the screws of the fan interacted with one of the three louvers for the vent. So some creative enlarging of the hole was required to make sure the vent was able to swing open freely. But eventually it worked.
Then I tackled cutting holes for the fans in the wall between the fridge and freezer. This was a gigantic chore. I made sure to start with existing holes in the wall from the air supply and return from the old fridge side setup. I borrowed a dremel from a friend, and got to work. It was a lot harder than I expected. The wall between the fridge and freezer was steel. It wasn't so hard cutting out the first part on the fridge side, but cutting out the size of the fans on the freezer side was a nightmare. There were components to protect and also it is VERY close quarters on the freezer side, so it was hard to fit me and the dremel in there with enough room to move my arms enough to make the fine motions necessary for good clean cuts. Eventually I succeeded.
Another lesson I learned was to make sure there was adequate clearance for all the wires that needed to go from the freezer side to the fridge side. The wiring I dealt with basically came into the unit on the fridge side, moved over to the freezer side at the bottom, and then came back in to the fridge side at the top. Plus I had to run the fan wires back into the fridge side to hook up to the temperature controllers in the door. The top fan had a convenient hole right below the main hole I was using and I was able to simply thread the fan's wire through that.
The bottom one took a bit more wrangling with the dremel until I got it in right. This was due to the wires in that location.
I spent a good deal of time measuring and planning at this point. The goal was to fit as many carboys in both chambers as possible. My largest carboys are glass and encased in a wooden frame to avoid breakage, so I wanted to make sure these would be able to fit, with airlock, in each chamber.
(Not my cold room unfortunately!!)
The back of my fridge side had a bit of a hump to it, so I also wanted to make sure I could build a little shelf back there and fit at least a better bottle with an airlock back there. So it took a bit to get it right, but ultimately the shelf between the two chambers roughly split the difference. Since I wanted maximum space inside, I figured all I would need to do was insulate the front and top of the bottom chamber to insulate the two sides from each other. Once i got the measurements set, I got a sheet of 1/2 inch plywood, and a sheet of R6 hard foam insulation. I also got a roll of soft foam weatherstripping, two hinges, and two sliding latches. My design was to screw four legs into the 1/2 inch plywood shelf. These would rest on the bottom of the fridge side. The rear of the shelf would rest on and be secured to two cleats that were mounted to the fridge with screws. The middle legs had a cleat mounted on them which supported the shelf that went from the hump to the cleat to provide a level surface for another carboy in the lower chamber. I already had a bunch of 1x4 material leftover from my carboy cage projects, so I used those for the legs and the cleats. I built a bit of a door frame with the front legs. Once I did a couple dry fits and had everything where I wanted it, I installed the cabinet.
Now it was time to tackle my least favorite part of the build, the electrical. One thing I figured out pretty quickly is that I would have to wire the lower Inkbird first, and then the upper one, because the screws to secure the wires are on top of the unit.
I used 14/3 Romex for most of my wiring but this was ridiculous overkill as the fans did not have a ground wire. Probably when I use a heating element it will but I will cross that bridge when I get to it. Plus, the solid core 14 gauge wire is RIDICULOUSLY unflexible. using it to mount to something like a door that is on hinges was difficult. Based on the number I used to strip wire in the fridge, I would guess that braided 16 gauge is plenty stiff enough. Just make sure you keep track of hot and neutral and you will be fine.
I noticed that both of the dual chamber builds I had seen before had run a separate AC line to the fridge to power the fermentation chamber side. I didn't really understand that at first, and my initial thought was that I would have the Ranco control the freezer side, and then just tap into the electrical harness on the fridge side to get power to my Inkbirds and the fans. This was a bad idea for two reasons.
The first reason why that is a bad idea is the fermentation chambers should be able to draw cold air or turn on the heater in the fermentation chamber side when the ranco has the compressor turned off.
The second reason is that I couldn't get the compressor to operate properly when I tried to pull power for the Inkbirds from the wiring harness.
For those two reasons, I went to Home Depot and bought a $3 two prong extension cord. I was able to run it through the bottom of my fermentation side through where a water line had come through, and then hook it up to the inkbirds, etc., that way. Everything worked great then. Ranco can have the compressor shut off, but the fans can keep blowing.
I was able to drop the temp on the fermentation side from around 79 to 50 overnight.
I'm still fiddling with temperature control and I expect that to be a work in progress. I actually removed some of the louvers this morning because i was unable to get the chambers to drop below 50. The fans do not blow as aggressively as you might think, the louvers don't really open that much, so when you are trying to get it colder it may be necessary to remove them to get the temps down. I will check back tonight and report.
That's pretty much it! Thanks for checking out my thread and thanks to the legions of handy HBT-ers who went on before to give me the inspiration to tackle this project. Feel free to ask me any questions below, happy to provide any insight I can.
