My neighbors bought a new residential fridge for their stick and brick, and it was a perfect fit in the receptacle.
However the fridge instructions said 2 inches of space was required over the fridge, and 1 5/8 between back of fridge and wall behind fridge. They had only 1/4" under a cabinet basically enclosed the whole top of the fridge.
I warned them this would cause the fridge duty cycle to increase a lot, but they really liked how it looked, being such a tight fit.
I said lets throw it on a Kill a watt, and My IR gun showed 120 degrees( 72 ambient) above and behind fridge within an hour of plugging it in.
The IR gun readings alone were enough to make my point. I modified their cabinet above fridge with a false back and opened up the cabinet so the fridge could breathe properly. The Kill a watt readings were not recorded before and after cabinet modification, though I do wish I had collected that data. Temps after venting cabinet above fridge were rarely over 92f in ~70F ambients.
My small DC compressor fridge can vent to RV exterior, or interior, or both. Venting condenser heat was a priority in designing the cabinet in which it is installed. One 80mm cabinet exhaust fan runs 24/7.
One can easily wire a 12v fan and it need not even cycle on and off with compressor. The Noctua NF-f12 moves 53CFM for 0.05amps and is very quiet. This minor electrical consumption will be negated by the lower duty cycle of the fridge, and decrease the time required to remove the heat from warm items placed within.
Premature Norcold DC fridge compressor failures of the 90's and early 2000 are attributed to improper installs where condenser heat evacuation was not a consideration of those installing them. The heat removed from box and generated by compressor motor, has to go somewhere. The better this heat can be transferred to atmosphere, the less energy it will use to maintain sub 40f temperatures inside.
