Replacement A/C's

Tiffin has used RVP(Coleman) for the past 5 years or so. As to your concern about The NEC code. Remember one thing- The Length of the run of 14 gauge wire is as important as the size. I will bet most residential runs of wiring for a appliance is 2 to 3 times the length of the run in a RV. The max length of most RV Romex runs will be 20 feet for the AC units on your size model. IF Tiffin agrees that back then the use 14 instead of 12, there are THOUSANDS of Tiffins out there with Roof AC's running on 14 gauge wire and 20 amp breakers. I am and have been a Tiffin dealer Tech for 34 years and I can state with certainty, that I have NEVER seen a Tiffin roof AC on a 15 amp breaker that was not a mistake from the Factory and all I had to do was connect the AC to the correct 20 amp that was miswired in the breaker panel. Doug