I just thought I'd note that older fridges didn't have that Yoder loop.
Older fridges had an electric mullion heater under the metal mullion to heat the mullion and keep condensation from forming on it. And, the manufacturer would put a switch in to turn that mullion heater off if it wasn't necessary cuz low humidity in the house would prevent condensation anyway.
Problem is, they called that mullion switch the "Energy Saver Switch" and people would invariably turn that switch to the ON position thinking that it needed to be in that position to save energy. In fact, the opposite was true. Turning that switch on turned the mullion heaters on, and in a lot of cases wasted energy.
Also, another very likely cause of a hot yoder loop is that the OP might have just put a lot of stuff in his fridge; like a case of 24 warm beer. The more warm stuff you put in the fridge, the more heat has to come out of the condensor, and the hotter that condensor coil (and hence yoder loop) will get. Once the beer gets cold, the temperature of that mullion should return to normal.
You can still buy those electric mullion heaters, but nowadays most people use them to warm their home made wine or beer to accelerate the fermentation process.