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Geocritter's avatar
Geocritter
Explorer
Jul 11, 2014

Running single rig AC unit on a 20amp circuit.

My RV is a 1994 33' Holiday Rambler. I have a question about running my rigs AC (single unit only). It’s been hot here in the Crater Lake area and I’d like to run my AC, my concern is that my 30amp service is hooked up to 20amp service via a 20/30amp adapter. Right now the only things I have that need power are my small electric refrigerator (it’s not an elec/propane unit) and my electric hot water heater. The other things are my laptop, additional flat screen monitor, and an inkjet scanner/printer.

Could I damage my single AC unit running it through a 20amp service with the load I’m running? The 30amp service I’ve had in the past has always handled it just fine. This is important and more than a simple comfort issue. I’m semi-retired and just received a large research/writing project with a very short deadline. It’s just too hard to work and think in this afternoon heat.

Thanks in advance for any insight y’all can give me regarding this issue.

Steve
Seeking Advice

23 Replies

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  • Water-Bug's avatar
    Water-Bug
    Explorer II
    Jul 11, 2014
    First thing to do is check the current draw of your AC. There should be a manufacturers tag giving the model number and electrical requirements. Second, the electric water heater is probably drawing nearly all the current availale, when it is heating water. Cycling between water heater and AC may be necessary to prevent overloading the circuit. Third, although most home wall sockets are wired to 20 amp breakers, the wall sockets themselves are only rated at 15 amps. True 20 amp sockets will usually have a pin that is verticle to and connected to the + . ( two parallel pins for + and neutral, with a round ground pin below and a pin verticle to the + pin.)
  • ScottG's avatar
    ScottG
    Nomad
    Jul 11, 2014
    Your probably close with all that other stuff running. You need to monitor the voltage to make sure it doesn't drop too low.
  • john_bet's avatar
    john_bet
    Explorer II
    Jul 11, 2014
    One word answer is no. A/c only, no heater,no frog. Then keep an eye on the adapter as it may get warm. A 20 amp circuit should only be loaded to about 16amps for continouse use.

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