Turning a Danby Refrigerator into a Fermentation Chamber

After much renovation purging, the last thing I need is more stuff. Except for homebrewing gear. There's usually something I can justify owning. 😁

Danby DAR044A5BSLDD

The family started asking for a list of things I would like for Christmas. The list this year was short but very specific:

• Inkbird ITC-308 temperature controller
• Danby DAR044A5BSLDD Compact Refrigerator

Put those two items together and you've got a fermentation chamber.

I picked this particular refrigerator because the evaporator is flat against the back of the interior. Most mini-fridges have the evaporator shaped into a "freezer" compartment on the ceiling. Not only does it take up needed space, it's tricky to move it out of the way without rupturing it. This Danby design also means there are no refrigerant lines in the top, so it's easy-peasy to drill a hole for a tap tower. If you're pressed for space, you could make this a kegerator/ferm chamber combo unit.

As for the Inkbird, it's an easy way to add temperature control without having to do any wiring. Set the temperatures you want, plug in the cooling and heating sources.

Modding the Fridge Interior

5gal and 2.5gal cornys (note the
can rack peeking into the right
side of the picture)

The fridge can be used without any permanent interior modifications but you will sacrifice some volume. This fridge has molded shelving on the inside of the door that takes up a fair amount of space, particularly the soda-can rack.

The most I could fit was a 5gal corny on the floor and perhaps two smaller cornys on the hump in the back. That rack won't allow for a second corny keg to sit on the floor. Smaller 2gal bucket fermenters fit easily.

More importantly, my 30L Spiedel fermenter and 6gal buckets won't fit without doing some cutting.

The molded door shelving looked like it could be cut away without too much difficulty. I found a YouTube video of a guy using a Dremel to cut along the outer edge. I had a Dremel somewhere, but didn't feel like digging it out. Also, noisy as hell. I figured I could brute force it with a utility knife and a screwdriver.

But to do that, I've got to get the door off.

Removing the Door

I started to take the plastic top off to get at the top hinge, but realized that would be more trouble than its worth. It was much easier to remove the bottom hinge instead. I gently rested the fridge on its back and removed the two screws holding it on. I was surprised that this fridge has only one adjustable foot on it, which makes it difficult to level. Once the bottom hinge plate was off, I slid the door off the top hinge.

Removing the Door Gasket

Removing the door gasket is simple. It more or less snaps into a channel that runs around the perimeter of the door. I peeled back one corner, then carefully lifted the gasket out. I placed it on a flat surface so it wouldn't warp while I worked.

 Cutting the Door Shelving

This part is probably the most dangerous. Not only am I working with a sharp knife, I'm trying to cut material that's tough and leaves sharp edges when cut. I wanted the gasket back to rest on plastic, so I was going to make my cut about 1/2" in from the gasket channel. The plastic makes a bend here, so there's an easy line to follow.

I started the cut by pushing the point of the utility knife into the plastic. I knew there was some foam insulation underneath, so I kept the blade short. It took some effort to make a cut in this material. I had to use both hands: one to pull the knife, while the other applied pressure to push the blade in and along the cut. The blade slipped out several times. The corners were particularly tricky since the plastic is thicker there.

Starting the cut

Working along the edge, about 1/2"
in from the gasket channel

Cutting the plastic is only half the job: The insulating foam fills all the voids underneath the plastic and is quite stiff, so that will need to be cut as well. I used a hacksaw-like blade to undercut the larger foam sections and peel the plastic and foam off the door.

Foam underneath shelving

Peeling away the lining and foam

After a while, I could peel away pieces of the molded plastic

Utility knife to cut plastic, small hacksaw to cut foam flush,
and pliers to lift and tear the plastic

After cutting the perimeter free, it's simply a matter of peeling away the plastic. It won't come off in one piece, so I made a few secondary cuts around the can shelving to make it easier. The edges are quite sharp, so wear gloves.

Door minus plastic shelving

Sealing the Foam Insulation

You could stop right here and reassemble the fridge. It will work just fine, but you run the risk of getting condensation into the door which can turn to mold and/or mildew. I've seen other builds use tape or a sheet of thin plexiglas to seal the inside of the door. Being a bit impatient, I wanted to use what I had on hand. So I used HVAC foil tape and a can of Flex Seal spray. I planned to use the Flex Seal to fill in the larger holes and provide an overall seal coat, then use the HVAC tape to cover the rougher cut surfaces. I emptied the whole can on this door in about 3 coats, then applied the tape. The tape is wider than the rough spots so it would make a good seal. It's not all that attractive, but hardly anyone is going to see it.

Applying Flex Seal

Applying HVAC tape

All done!

The last steps are to snap the door gasket back in place and rehang the door on its hinges.

Setting up the Inkbird

The Inkbird ITC-308 can control one cooling device (the fridge, in this case) and one heating device (a Ferm Wrap, which I bought later). You set the temperature you want to hold and how much wiggle room you will allow (hold at 65F, but allow to rise as far as 67F before cooling or drop to 63F before heating). You can also set a compressor delay so the refrigerator motor doesn't burn out from starting up too frequently.

I will eventually drill a small hole in the back left corner of the fridge to thread the temperature probe through, but for my first batch of lager, I just closed the door on the wire.

Once I had it set up, the Inkbird was pretty easy to use. It kicked the fridge on right when I wanted it to. Lagering was pretty easy. Fancier models can set a schedule to ramp temperatures up and down over several days, but it wasn't much trouble to make my changes manually.