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15 amp receptacle on 20 amp circuits, can I replace with 5-20?

Discussion in 'Charging Standards and Infrastructure' started by LetsGoFast, May 8, 2015.

  1. LetsGoFast

    LetsGoFast Active Member

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    My house appears to have used 12 gauge wire for every branch circuit, although some are on 20 amp breakers (the garage, kitchen, bathrooms for sure) and others are on 15 amp breakers. However, every receptacle is a standard 5-15 -- nowhere in the house did they install any 5-20 receptacles.

    My research suggests that this is perfectly fine under NEC because the assumption is that you are unlikely to draw the full 20 amps from any one outlet. I further assume that the 15 amp receptacle itself might fail if I pushed 20 amps through it. Is there any reason I couldn't replace one of the 5-15 receptacles in the garage with a 5-20 if I wanted to be able to draw 16 amps continuous instead of 12? As I understand the problem, if the breaker and the wire already are 20 amp, that would be the only issue. Of course, I'd need to ensure that there were no other loads on the circuit at the time.

    This would only be a back-up solution for the rare situation where I cannot park on the proper side of the garage to reach the HPWC.
     
  2. tga

    tga Active Member

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    If there's already a 20A breaker with the 12ga wire, go for it.

    If the is a 15A breaker and 12ga wire, I'd personally be leery of changing the breaker to 20A and replacing the outlet, if only because it's hard to definitively say there is no 14ga anywhere in the circuit. For example, if there's a few daisychained outlets, you need to open up all the outlet boxes and confirm the size of all the wire. Even then, you're still assuming there are no gross NEC violations, like buried splices (yes, I've seen that done:scared:)
     
  3. mspohr

    mspohr Active Member

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    If you have 12ga wire from the panel to the breaker (and no 14ga wire on the same circuit), you can replace the breaker with a 20a breaker and the socket with a 20a socket (NEMA 5-20). You'll be able to safely draw 16amps continuous from this assuming no other loads on that circuit.
    It's common to install 12ga wire with 15 amp breakers and sockets since this has only a small extra cost for the wire and gives you a safer installation with less voltage drop.
     
  4. LetsGoFast

    LetsGoFast Active Member

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    Just to clarify, the breaker is already 20amp -- just the receptacle is 15 amp.
     
  5. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    As tga mentioned, you need to guarantee that 12 AWG was used the entire length of the circuit, and that 14 AWG wire isn't present between any junctions in the circuit. That's easier on new construction where you knew what's in the walls - but in older construction it's quite a hassle.
     
  6. davewill

    davewill Member

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    I would add checking to see how the outlets are wired. If they are daisy-chained through the outlets, I would change that so that each outlet is fed with a short pigtail instead.
     
  7. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    Oh, then you're good. Replace with 20A receptacles at will.
     

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