This is a Traulsen design. At the time they were trying to compete with Sub-Zero for the residential market.
The first design used a static condenser mounted on the back with a 1” X 6” squirrel cage fan on a rheostat blowing from the top down. (Without the fan the compressors were over heating.) This same model had the freezer evaporator in the walls of the freezer. It was a lot of fun telling a customer that just paid 4g’s (mid 80’s $) that the freezer was a manual defrost. Along with the compressor noise issue this model was soon put to rest.
The new design used Tecumseh AE4440 & 4430 pumps (I believe) with a 2 circuit condenser coil-1 fan. These are not Tecumseh condensing unit’s just there compressors. Everything wrapped with insulating sheets to keep the noise down. (even they learned by there mistakes and did away with the in wall evaporator)Unfortunately they couldn’t compete with Sub-Zero and the others and the entire line was dropped.
Old man Traulsen, yes that was his name, started as a tech (mechanic as us old farts used to be called) and built the company. He took pride in seeing his name all over the world.
As a young mechanic I was sent to his apartment on 5th Ave in Manhattan. Getting off the service elevator there was no question which door was his. All Stainless Steel with the same Traulsen label.
There is no better manufactured piece of refrigeration equipment out there. Compressors, Fans, Controls etc will always fail but the Traulsen cabinets were built like a tank. I still see and service units 30 and 40 years young.