[VAL] Dometic Question

[c-l@xxxxxxxxxxx]

Just purchased a 1962 Tradewind. It has waht looks to be the original refer.  It 
is a Dometic.  The only numbers I can find are  M-50, and Unit Type 75A.  I m not 
sure of the propane operation, but when I plugged in the trailer to the 110 power 
source, the coils inside the unit smell very hot.  I did not see any control for 
temp setting on 110, there is a knob for temp setting when on propane.  On the 
wall, below the thermostat for the Air, is another control, says Dou-Therm. Does 
anyone have one of these units, that could tell me about it? The P/O said they 
didn't use it because people said it was unsafe.  I could not find the electrical 
connection for the unit, where is it?  Also, near the top of the unit, there is a 
hole in the wall, and then seems to travel up the wall inside the wall to a vent 
on the roof. Is this a correct set-up.  Thanks in advance,
Chuck & Lynn