How to Convert a 4-Prong Dryer Cord to Fit a 3-Slot Outlet
If you have a 4-prong dryer cord but hookup 3-prong outlet in your home, you likely need to update it according to new electrical guidelines. But don't worry, it's an easy issue to fix. Due to changes in the National Electrical Code NECclick at this page recommended wiring for electric clothes dryer outlets changed in Before the change, dryer outlets were 3-slot devices that accepted 3-prong cords. This configuration did not include a dedicated ground connection; the dryer's equipment ground case ground was connected to the neutral conductor in the dryer cord and the household circuit.
Since the code change, new dryer outlets must be wired with separate neutral and ground wires. These outlets have four slots and will accept only 4-prong electrical cords. Homeowners owning older dryers with 3-prong cords are sometimes perplexed when they move into a home that has a newer 4-slot outlet.
In this instance, the solution is to replace the old 3-prong cord with a 4-prong cord to match the new outlet.
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Fortunately, it is a very easy project. However, be aware that it's still legal to use 3-slot outlets—the code has no requirement that they must be replaced with 4-slot outlets. This is why new clothes dryers are generally sold without any power cord at all so that you can install whatever cord style matches your outlet. The key difference in the wiring configuration between 3-prong and 4-prong cords is that, with the older setup, the 3-prong cord has only two hot wires and one neutral wire—there is no separate ground wire.
Such a configuration creates a chance of shock hookup the rare case that the ground wire opens up. The old 3-prong configuration would trip the breaker in the case of a short circuit, but in the broken ground condition, the entire bare ground and metal case would be energized.
This was the reason the code changed to require the 4-wire configuration. A 4-prong cord, by contrast, has a separate ground wire, which means that the dryer's neutral and ground are not connected, thereby minimizing the chances that the appliance's metal case wire become energized during an open neutral condition.
When you convert from the 3-prong to the 4-prong configuration, you must wire sure that the dryer's neutral terminal is not connected to the case wire. Because you are not working on household circuit wires while installing the cord, this is a very safe project. However, it is crucial that the wire connections you make when attaching the cord to the appliance are correct and very secure. Loose connections can lead to short circuits and sparking once the appliance is plugged in for use. Never plug in a dryer cord unless it's fully connected to the dryer.
Plugging in a cord sends volts of electricity to the bare dryer ends of the cord. If the ends touch together or touch you, they'll create a potentially lethal short circuit. Unplug the dryer from the electrical source, then remove the metal plate covering the cord's wiring connections on the back of the dryer.
It should be directly above where the cord comes out. Use a magnetic screwdriver or nut driver or socket wrench to remove the plate's screws. With magnetic tools, you're less likely to drop screws inside the dryer. Remove the screws on the strain-relief fitting that secures dryer cord to the back panel of the dryer. Separate the two halves of the fitting and pull them out of the hole one at a time.
Disconnect the old 3-prong cord by removing the three screws or nuts with studssecuring the wire ends to the dryer's terminal block.
The two outer terminals are the hot terminals, and the center terminal is the neutral. Pull the cord out through the hole to remove it from the dryer. Disconnect the dryer's neutral wire from the ground screw to convert the wiring configuration from a 3-prong to a 4-prong. You may have one of two different configurations:.
Install the single dad dating childless 4-prong cord by inserting the loose wire end through the hole in the dryer's back panel and making the following connections:.
Tighten each terminal screw firmly, and double-check them to make sure they are tight. Slip the tab of the top half of the wire and position the dryer semi-circle of the fitting over the top of the cord. Repeat with the bottom half of the fitting below the cord. Squeeze the two halves together click to see more secure the hookup with the fitting screws. Snug the screws so the cord is held firmly but is not deformed by the pressure. Your old strain-relief fitting probably won't work for your new 4-prong cord.
A 3-prong cord typically is flat, while a 4-prong cord usually is round and requires a fitting with a rounded area in its center. Do not use a strain-relief fitting that doesn't fit the cord. Reinstall the cover plate with its screws.
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To test the dryer for proper operation, article source the dryer's control knob s to confirm that everything is in the off position, then plug the dryer into a 4-prong dryer outlet. Run the dryer for a few dryer to make sure everything works.
Be sure to connect the dryer vent duct if you removed it or if it's a new installation before using the dryer. This is because the adapter might not provide a grounding pathway for the electrical current, leaving you vulnerable to electrical shocks, fires, and more. Yes, the National Electrical Code now requires that dryers have a ground wire.
This allows current to be rerouted safely to avoid fires and other electrical hazards. Whether or not the ground and neutral wires need to be connected to the dryer depends on the type of prong used. For a 3-prong cord, the neutral wire must be attached to the dryer metal ground connection.
For a 4-prong cord, the ground and neutral wires should not be connected. Electrical Safety. In Hookup Article Expand. Differences in Wiring. Safety Considerations. Project Overview. Warning Never plug in a dryer cord unless it's fully hookup to the dryer.
Materials UL-listed, amp, 4-prong dryer cord Strain-relief fitting for 4-prong cord. Remove Cover Plate for Electrical Connections Unplug the dryer from the electrical source, then remove the metal plate covering the cord's wiring connections on the back of the dryer. Tip Use a magnetic screwdriver or nut driver or socket click at this page to remove the plate's screws.
Installing a 3-Prong Power Cord on Your GE or Hotpoint Dryer: A Step-by-Step Guide
Tip Your old strain-relief fitting probably won't work for your new 4-prong cord. What color is neutral on a 4-prong dryer cord? The white wire is neutral on a 4-prong dryer article source. Is it safe to use a prong adapter? Does a dryer need to be grounded? Should the ground and neutral wires be connected to a wire Article Sources.
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