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TireKicker · 12-11-2016, 01:10 PM

Hi everyone. Our's is a 1999 National Tropical 6350. 30 amp shore power. I've read discussions of adding a separate 120Volt 20amp cord to the rear A/C. Further, I'm interested in doing this. Could someone please tell me where on/in the coach to find the wiring that supplies the 120volts to the Rear A/C? My intentions are to create a "Pig tail" that could be plugged into a 20 amp receptacle at a campsite. Then to add an outlet box in the compartment to plug into for use when running the generator. To further, complicate this the coach has a power management system to prioritize power usage. I know just about enough on this subject to get me into serious trouble. Thanks for the help.

Beau388 · 12-11-2016, 01:40 PM

Hopefully all 120V coach's wiring goes to and from the circuit breaker panel. If the coach came with two A/C, then you should have two different circuit breaker's. The input to the rear A/C can be removed and spliced to hd extension cord (12 ga -20 amps). You cannot operate that isolated A/C for the generator (no transfer switch) and there will be no surge, over/under voltage protection.

TireKicker · 12-12-2016, 06:30 AM

Do you think that I could take the 20 amps out from the generator to an outlet box with a 20 amp breaker and use that to plug the 2nd A/C "Shore Power Cord" into when running on generator alone? In other words I could plug into the campground outlet OR plug into the generator's 20 amp outlet that's on a breaker? On 2nd thought the generator outlet has it's own 20 amp breaker so wouldn't adding the breaker in the 2nd outlet be redundant?

Beau388 · 12-13-2016, 06:07 AM

Not knowing the wiring of your coach, I would not hazard a guess. If you generator is a 4000 watt then I would not try. Most 15,000 BTU A/C require 1,900 watts on 95 degree days. A 4,000 watt generator should not be loaded to more than 75% for long periods and altitude also effects output. So unless you have a 5,500 watt generator I would not try it.

wa8yxm · 12-13-2016, 09:32 AM

As was stated, it depends on the coach.. But I might have a "Clue" alas only a clue.

Does your RV have a Generator? IF so does that generator have two circuit breakers, one 20 amp, one 30? Well if that is the case the somewhat fancy Automatic Transfer Switch may route power to that Rear AC via that 20 amp breaker.

SO the Generator Junction Box is the answer, this is often in the compartment to the left of the Generator.

Suspect 2 is the Auto Transfer Switch by the way
Or if you have it an energery manager (load shedding type) but I have no direct knowledge of those, these are suspects only.

HOWEVER I stress.. THIS IS ONLY A CLUE. you are going to need to do some heavy duty testing to confirm.

First step. Without shore power (leave off at least 3 mintues) fire up Generator than manually turn on Rear A/C (blower mode is ok) and turn OFF that 20 amp breaker.. Did the Rear A/C die? (yes = Good) did anything else (yes = bad) If so the odds are improving.