How to Wire a Three-Prong Outlet to a Four-Prong Outlet

Sarah Haynes

Did you just buy a new house and now your dryer cord will not match up with the new 4-prong outlet? In 2000, the code was changed that all homes now have the 4-prong outlet, which is safer than the older 3-prong outlets. Many people still have dryers with a 3-prong cord.

Wire a Three-Prong Outlet to a Four-Prong Outlet

Even now, if you buy a new dryer, most stores will give you either cord depending on the outlet in your home. While it's fine to upgrade to the new 4-prong outlet, a 4-prong outlet should never be downgraded to 3-prong. Here's how to wire from 3 to 4 prongs.

  1. Remove the old 3-prong dryer cord. Unplug the power to the dryer. Locate the access panel on the back of the dryer.

  2. Unscrew the access panel, which will normally be two or four screws holding it on and located near where the cord comes out of the dryer.

  3. Examine your terminal block, which should now be exposed from taking off the back panel. You should see three wires, red, white, and black.

  4. Loosen the bolts or nuts holding the wires down and take the wires off the terminal block. Be careful not to loosen these nuts or bolts.

  5. Disconnect the bonding strap, which will be either a metallic strip or green wire connected to the middle white wire terminal, which is neutral, to the green screw above the white wire.

  6. Loosen the connector piece's screws that hold the dryer cord in place

  7. Remove the old 3-prong dryer cord and set aside. Insert the new 4-prong dryer cord through the same hole and connector piece and retighten the connector's screws.

  8. Match up each wire to the terminal block. The white will be in the middle, the black and red will be on the outsides. The new cord also has a green wire ground that will be connected to the green ground screw that is on the dryer's frame.

  9. Place the access panel back in place over the terminal block and screw the screws back into place.

  10. Turn off the breaker to the dryer. Plug the new dryer cord into the 4-prong outlet. Turn the breaker back on.

  11. Tip

    If you have trouble locating your access panel, refer to your manufacturer's manual. An adapter cord can be bought at almost any home improvement store for about $15.


    Be sure to remove the bonding strip. If it is not removed, you will get shocked touching anything metallic on the dryer.