Why can't reefer connect to the tractors power source?

There was experiments decades ago, probably before I became a trucker where they thought maybe they can heat and cool the tractor interior along with the electrical needs. That did not go over too well for a variety of reasons. In those days the old grizzled owner or dispatcher will yell, TOO FANCY. for them old iron back then.

I had a old Carrier mechanical on a 45 foot trailer. And sometimes you jumped it. I also wondered about the food product as well. The temperature dials had no meaning, having been worn off long before I was born. If you are cold inside that thing it's time to put the icecream in it. About all it's good for One set point. Anything else in between too #### cold and way too hot was a gamble.

 

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