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rob_engineer's avatar
rob_engineer
Explorer
Jun 23, 2015

Can I run 15,000 BTU air cond with RV plugged into my house?

I have 39ft Gulfstream Friendship 102 diesel class A. My 15K roof air works when under generator power, but overheats and trips breaker when the RV is plugged into my house. I have a normal 20 amp outlet on my house. I use a 50ft, 10 gage cord from the house to the 50 amp cord on the motorhome. If I shorten the 10 gage cord, is there a chance that my household power will be enough to power the air conditioner? In my current setup, the voltage to the air conditioner drops from 119 (no load) to 101 (full load). While on generator power, it only drops to 113 volts full load. I like to hang out in the RV in my driveway. What do I need to successfully run the 15K roof air, other than use my generator? I am also considering putting a portable air conditioner in the RV for driveway use instead of using the roof air. Your thoughts?

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  • 2chiefsRus's avatar
    2chiefsRus
    Explorer
    Jun 23, 2015
    If you turn off the converter/charger, you will remove the load of charging the batteries while you are trying to run the AC. We had friends who had a similiar problem - it turned out the freezer in the basement was on the same circuit the RV was plugged into. If the freezer wasn't running, the AC was fine but if the freezer kicked on, not enough juice left to run the AC.
  • rob_engineer's avatar
    rob_engineer
    Explorer
    Jun 23, 2015
    2oldman wrote:
    rob_engineer wrote:
    I use a 50ft, 10 gage cord from the house to the 50 amp cord on the motorhome. If I shorten the 10 gage cord, is there a chance that my household power will be enough to power the air conditioner?
    This is more than likely the problem. There's too much voltage drop using that cord. Shortening it may help. Be sure your converter is off.

    Were I you I'd be using a genuine 50a extension cord.


    I should have been more clear. The breaker that trips is the 20 amp breaker in the RV, not the breaker in my house.
    Can you elaborate on why the converter needs to be turned off? I'm not really sure what you mean or why it's important.
  • fla-gypsy's avatar
    fla-gypsy
    Explorer
    Jun 23, 2015
    A dedicated 20A circuit will run the AC but you will be heating up the cord pretty hard depending on the distance and may cause a meltdown.
  • TxCowboy's avatar
    TxCowboy
    Explorer
    Jun 23, 2015
    I had a 75 foot 12 gauge extension cord running to my RV and did the 120VAC to 30 AMP to 50 AMP connections. Had the RV plugged into this configuration during the entire off-season and ran the AC, TV, DirecTV wireless modem system, DVD player, and the RV's 12 volt system with no problems what so ever.

    Just make sure that the 120VAC connection from the house doesn't have anything else drawing off that circuit. Since it is tripping, it may be that you're running something else off that circuit that is exceeding the breaker. Also, make sure it's a 20 amp circuit, not a 15 Amp. If it is 15 amp, you're AC's peak draw (normally on start-up), might be exceeding 15 amps.
  • Grumpy374's avatar
    Grumpy374
    Explorer
    Jun 23, 2015
    The only way to do it is to do it right. Have an electrician run a dedicated 50 amp service from your box, to an outside outdoor rated box. That way you'll be able to run everything and not worry about tripping breakers. Now your running off 20 amps, and if you turn on anything else thats on the same circuit it will trip the breaker. That plus the length of your cord, on 20 amp service will give you nothing but problems.
    50 amp service with a 50' cord should be no problem at all.
    Grumpy
  • imgoin4it's avatar
    imgoin4it
    Explorer
    Jun 23, 2015
    If it is tripping the 20 amp house breaker obviously you cannot run the coach acnd without tripping. You can take a look at what else you may have on that circuit that could be disconnected and maybe reduce the load or more than likely you will have to get a qualified electrician to see what is required to install at least a 30 amp circuit.
  • raindove's avatar
    raindove
    Explorer
    Jun 23, 2015
    ~We have a 30 amp receptacle at home where we park/store our Class A.
    Runs the a/c fine.
  • 2oldman's avatar
    2oldman
    Explorer II
    Jun 23, 2015
    rob_engineer wrote:
    I use a 50ft, 10 gage cord from the house to the 50 amp cord on the motorhome. If I shorten the 10 gage cord, is there a chance that my household power will be enough to power the air conditioner?
    This is more than likely the problem. There's too much voltage drop using that cord. Shortening it may help. Be sure your converter is off.

    Were I you I'd be using a genuine 50a extension cord.
  • Halmfamily's avatar
    Halmfamily
    Explorer
    Jun 23, 2015
    I ended having my brother install a 50amp circuit at the end of my house to plug in my fifth wheel. The 20amp just wasn't cutting it. I could run my 13500 but not my 15000 A/C. Now I can run both A/Cs watch TV and do anything I need.

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