[thenewkid64]

Ted,

You will need to do some investigation but I think if you pull up the alumimum sheet that is screwed to the floor for will find the remnants of the air intake for the refer. Prior to 75 ( I think) intake air was drawn from under the trailer, later models had an external vent. You may have to pull another sheet of aluminum that will be obvious when you look underneath from the outside.