Ask The RV Doctor – Power Choice
Q: We recently purchased a 24′ Aerolite RV. We see that many sites offer 30 or 50-amp service and we are uncertain as to which one our RV would require for running a heater, air conditioner, stove, refrigerator and small electric appliances. Can you advise us as to which service to request? —Kathy Cunningham, Cicero, NY
A: Kathy, many campsites equipped with a 50-amp service will also have a 30-amp connection located on the same pedestal. The service your unit requires is always dictated by the size and rating of the power supply cord (shoreline cord) on the RV. If your cord has three prongs, it’s most likely a 30-amp cord. I’m guessing this is what your 24′ will have. If it contains four prongs, it’s 50-amp. A word of caution; always verify the voltage and the polarity of that voltage before plugging in at any site pedestal. Be sure the voltage falls between 103-volts and 125-volts. It’s wise to carry a small volt-ohmmeter (VOM) and an inexpensive polarity tester while traveling. Your air conditioner is indeed a 120-volt AC appliance, but your furnace is probably powered by 12-volt DC (battery power) so it does not directly factor into the shoreline amp requirement. Keep in mind you have two different and separate electrical systems in your rig. However, if you’re talking about a small, portable, aftermarket plug-in ceramic heater, that would also be 120-volts AC, so it would draw current from the park pedestal and factor into your overall requirement. Your maximum limit, however, is the rating of the shoreline power cord and the main breaker.