I just bought a 15,000 BTU window AC unit. The plug is supposed to be 3 prong, but it was broken when I took it out of the packaging. The 3rd prong was missing and looks to have been snapped off.

Can I plug it into a 12 gauge extension cord that has a 3 prong plug and plug that into a 3 prong outlet without it starting a fire?

Will it ground the unit?

  • Does it have a GFCI on the end of the cord? May 25, 2022 at 7:08
  • 7
    You just bought a brand new item and found it to be defective. Contact the manufacturer or place of purchase to politely request a return of the defective item and a replacement for it. You shouldn't have to jump through any hoops at all to overcome a manufacturing/packaging/shipping defect.
    – FreeMan
    May 25, 2022 at 11:43
  • 2
    Also, NO, plugging a 3prong plug with the ground missing into a 3-prong receptacle will not magically ground the device any more than plugging a 2-prong plug into a 3-prong receptacle would ground the device. Without the pin making contact, it will remain ungrounded.
    – FreeMan
    May 25, 2022 at 11:47
  • You can buy a replacement 3-prong outlet at any hardware store. However, if you don't know this you should probably get someone else to fix it.
    – Hot Licks
    May 25, 2022 at 13:01
  • Quite possible that the unit was damaged (perhaps intentionally) and returned, resealed, and sold to you. I'd take it back, particularly on the chance that removing the ground pin was a willful act by the original purchaser in order to plug into an ungrounded outlet...
    – Jon Custer
    May 25, 2022 at 14:34

2 Answers 2


Safest option is to fit a new 3 pin plug.

Trying to rely on a broken prong is not wise or safe.

If you cannot fit a new plug, then get someone who can.

  • 5
    I should call the company and have the unit replaced, that's an option.
    – Kerry
    May 25, 2022 at 6:04
  • 2
    @Kerry I assumed that by posting here, you had considered, and rejected, returning the unit for various possible reasons.
    – Solar Mike
    May 25, 2022 at 6:42
  • 3
    @Kerry If bought new, That is the best option, since the unit is in an unsafe condition to use. Replacement plugs easy to buy and place on the cord, but would only use if the unit was second hand or had it for a some time.
    – crip659
    May 25, 2022 at 9:26
  • 1
    On many (most?) new portable air conditioners, the plug is "not just a plug" - it has a built-in GFCI, so replacing with a normal plug is not suitable (and foolish as the device appears to be defective as purchased, new.)
    – Ecnerwal
    May 25, 2022 at 13:23
  • @Ecnerwal going by the post from the OP - they don’t mention a bulky GFCI plug… And perhaps you need to make your comment more general as it may apply to the other posted answer.
    – Solar Mike
    May 25, 2022 at 15:02

Plan A - contact the suppliers, explain the problem. They should supply a safe replacement.

Plan B - assuming it's a standard 3 pin plug, cut off the broken one, and replace like for like, also assuming you are experienced enough to do that. It may well annul your guarantee, though - check with the manufacturers.

Plugging in without the earth pin connected will not start a fire, but will end badly if there's a problem - someone could be electrocuted. If that earth pin was plastic - highly unlikely - then you could do as you suggest, as the unit may be double insulated, and not require an earth, but I doubt that: it's just that plastic pins break off more easily.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.