184w CFL Stealth Mini Fridge

So here's what I've been working on for the last couple months.

Project: Turn a broken 4.4cu ft mini fridge I got for free locally into a semi-automated, completely stealth grow box.

First Grow Journal: https://www.rollitup.org/t/first-grow-3-strains-184w-cfl-mini-fridge.954055/

Prep: First I gutted everything that made it a fridge. I had a friend purge the refrigerant for me so I could remove the compressor and lines safely. I removed the shelving on the inside and the separate section for the freezer. I took off the door and rubber seal, using a Dremel to cut out the plastic that would have held cans and bottles on the inside. A couple screws later and the temperature controls were removed, leaving me the perfect wires for lighting already ran to the inside. I plan to cut out the step at the bottom later so there is more floor space inside.

Reflectivity: To line the inside of the fridge I used about half of a 25 sqft roll of Reflectix insulation from Lowes and aluminum HVAC tape. I measured the dimensions, cut and taped it to the inside. The ceiling of the box doesn't matter. Before reattaching the door I also insulated it. The plastic cutout when screwed back on over top made a tight seal with the insulation.

Exhaust: At the top I cut a 4 inch hole which I tapered on the inside to fit a 120mm 12v exhaust fan rated at 121cfm. I used silicone around the edge of it to make it airtight and 2 threaded rods through the back of the fridge to hold it in place. Using my 3D modeling experience I designed and 3D printed a custom 4 inch elbow to fit a Can Filter 1500 flange which was also printed. It was siliconed over the 4 inch hole to attach the filter vertically on the outside. This keeps it out of sight when the fridge is against a wall and it sits as close to the fridge as possible to save space.

Intake: One 2" hole was drilled on each side of the fridge at the bottom. Fabric from some General Hydroponics bandannas are covering the holes as a temporary filter. When the door closes you can see they get sucked in from the pressure so no worry about smell. Eventually I'll be 3D printing a light trap for each hole and air filter mounts.

Electrical: I used the existing fridge wiring at the back and added a 24 hour timer in line with the wiring that runs to the inside of the fridge. This controls 184 watts of CFL bulbs (4x 23w 5000k & 4x 23w 2700k). Branching off the existing wiring I also added a 12v step down for the exhaust fan. The fan is currently controlled by a DC motor controller at a constant speed. Im looking into having the fans controlled by temperature/humidity or an Arduino instead of having just one set speed. Wiring works for now I'll tidy it up eventually.

It's still a work in progress and has turned into more of a hobby than anything. Let me know what you think!

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Akhead

Member
I have this exact fridge that im wanting to turn into a stealth grow box just need the right design! What kind of fans did you use for the carbon filter? And do you have intake fans or just holes for airflow?
 
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