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Terry J. Sturgis
06-13-2011, 11:59 PM
I installed a new Dometic Duo Therm Penguin 13,500 in the rear bedroom. My motorhome has a 30 amp service soooo.. there is a 20 amp breaker in the main panel that runs the front air. The rear air conditioner runs off the generator only.
There is no room to add a breaker in the main panel to add a additional 20 amp breaker to run both airs on house power and I assume that I cannot run two AC's with 30 amp power annyway. Any suggestions from the POG brain trust. Thanks.

jack14r
06-14-2011, 05:33 AM
Most roof airs draw about 12 amps each,but on start up they will draw much more,if you can change the panel and get another 20 amp breaker you could possibly run both if you controlled the other loads.

Jon Wehrenberg
06-14-2011, 06:14 AM
Most breakers are good for continuous duty at about 80% of their rating. So a 30 amp shore power breaker can theoretically handle 24 amps which is just about the amount two AC units will draw as Jack points out. It is possible a 30 amp breaker can handle more continuously but the power outlets in a lot of campgrounds are old, not replaced until they fail and often have loose connections which will tend to increase the current draw.

Short of completely revising the power supply to the coach by going to 50 amp, ....OR.....setting up a dedicated cord to plug into the 20 amp outlet on the camground power outlet (paralleling the power to the AC unit from the generator) I don't see any other choices.

HarborBus
06-14-2011, 09:22 AM
Check your breaker box you may be able to add another 30 Amp breaker if a couple of existing breakers can be changed out with thin breakers making room for another 30 Amp breaker which should be available at you local home improvement store.

BoaterAl
06-14-2011, 09:59 AM
Terry.
I could run 2 A/C 's in my storage building plugged into 30 amp service. This was on the Country Coach Affinity with all other electric draws off. Turn off the electric hot water service and locked in the a/c to run continuous. It wasn't the most ideal service and rarely did it at any campground with only 30 amp service.

gmcbuffalo
06-14-2011, 10:27 AM
Terry I think Jon nailed it with his suggestion to parrallel circuit for the rear AC. Put a transfer switch between the generator and AC with 20 amp circuit breaker boxleading to the AC unit. The third leg of the transfer switch would be a dedicated cord to the 20 amp outlet on the campground powerstand.