Low Voltage Wiring Question For Walk In Cooler

Hello all, I am attempting to make a small storage room on the back of my house into a walk in cooler for dry aging chicken, pork, venison, etc. using a window AC unit. I got the idea from this guy here: https://archeryrob.wordpress.com/2017/11/07/deer-cooler-with-a-diy-coolbot-clone/  

Basically one controller (Inkbird) keeps a contact closed, running the compressor as long as the temperature is above the setpoint. There is also a low temperature limit switch which opens a contact if the temperature gets too low, to prevent the coil from freezing. I did this with a cheap widow AC I had and it functions, but the unit did not have enough capacity to get the room down to the desired 40°F

I found a larger 12,000 BTU AC, but when I opened it I found is wired differently from the smaller AC. The original small AC had a 16 gauge wire coming from the compressor into a small box that was connected to the temperature control dial. This also had the wire to the thermistor coming out of it. I cut that wire, connected it from the compressor to the Inkbird, Inkbird to the low limit temperature switch, switch to the thermostat dial/thermistor on the AC. The new 12,000 BTU unit has the wiring from the compressor going into a capacitor and some 28 gauge wire from the thermistor into a control board. I'm unsure how to proceed and I'm worried about frying the control board troubleshooting. Attached is a picture of the controls board area of the new AC unit. Any advice would be greatly appreciated.

Hi, interesting project. And welcome aboard!

Are you pulling the watts to run these AC units from the electric grid? That's a lot of energy, and I hope your modifications respect that.

I am leery of bypassing control circuitry that is operational unless you have full schematics and the training to understand them. Frying a compressor is one thing. A fire is a helluva lot more serious. My 2c.

Hi Douglas, thanks for the welcome.

Yes, the Inkbird controller uses 120V. I unfortunately have been unable to find any wiring diagrams from the manufacturer.

I am leery of bypassing control circuitry that is operational unless you have full schematics and the training to understand them..

That makes 2 of us.

In Thailand some fellow locals do it this way.
They changed it recently and use a modern airco inverter as it is more energy efficient.

I also have no clue how they do it, but I have no trust in their twist wire and tape technology
even I plan to build it into an underground or root cellar to cure hams, sausages and bacons.

By them it is looking fine and they explained me with their broken English its all about cheating the temperature feeler by moving it from the aircon into the room.

But I will follow this post until some graduated electrician will post here what's that all about and how to connect it safe.
Energy efficiency is also an issue.

Till now I set my loving eye on reliable wine cooler units for wine cellars as they are for 4000 USD tailor made incl. humidity controller.
Just what a professional cellar needs to produce some high class hams & Co..