How To Change 3 Prong To 4 Prong Dryer Cord

Are you looking to upgrade your dryer’s electrical safety and compliance? Changing from a 3-prong to a 4-prong dryer cord is a wise decision. This article will guide you through the process, ensuring a safe and efficient upgrade.

The 1999 edition of the National Electrical Code® (NEC®) first introduced the requirement for a separate ground wire for ranges and dryers. This is also in the 2002 edition as well as the current 2022 edition.

Difference Between 3 Prong To 4 Prong Cord

The difference between 3 prong and 4 prong dryer cords is in the wiring configuration. The 3 prong cord has only two hot wires and one neutral wire, while the 4 prong cord has a separate ground wire.

3-Prong Dryer Cords4-Prong Dryer Cords
Design and UsageHistorically standard in homes built before the mid-1990s. Consist of two hot wires and one neutral wire.Introduced to improve safety, now standard in new home constructions and updated electrical systems. Consist of two hot wires, one neutral wire, and one ground wire.
Grounding MethodThe neutral wire also functions as the ground connection, combining grounding and neutral functions in one wire.Features a separate ground wire, providing a distinct and direct path for grounding separate from the neutral wire.
Safety ConcernsDesign poses a significant safety risk due to the combination of neutral and ground wires, leading to potential electrical hazards, especially in case of a neutral wire break or loose connection.Greatly reduces the risk of electric shock and other electrical hazards. The separation of ground and neutral wires ensures safer operation.
Regulatory ComplianceNo longer compliant with modern electrical codes in new constructions or major renovations.Complies with modern electrical standards, such as those set by the National Electrical Code (NEC), requiring 4-prong dryer outlets in new constructions and updates.
This table summarizes the key differences between 3-prong and 4-prong dryer cords.

The old configuration has no separate ground wire. The new 4 prong drier cord has the dryer’s neutral and ground are not connected together. If you want to change the 3 prong to the 4 prong dryer cord configuration, you must make sure that the dryer’s neutral terminal is not connected to the case ground. 

All dryer and range receptacles installed after 2000 are required to be the 4-wire type. This would require a 4-wire cord. All dryer and range receptacles installed before 2000 are the 3-wire types. If a 3-wire receptacle goes bad, you are permitted to install a new 3-wire receptacle.

However, if the cable for the 3-wire receptacle goes bad or if you change the location of your 3-wire receptacle, you are required to upgrade to the new and safer 4-wire type.

Dryers and ranges are not sold with a particular cord attached because of this requirement. When you purchase a new dryer, the appliance store will ask if you want a 3-wire or a 4-wire cord. Both cords are rated 250 volts and 30 amps, as are all household electric dryers.

How To Change Dryer Cord – Steps-by-Steps Guide

Changing the cord on your dryer, particularly from a 3-wire to a 4-wire setup, is a task that you can accomplish with the right tools and guidance. This guide provides a step-by-step approach to safely and effectively change your dryer cord. Before starting, it’s important to gather all the necessary tools for a smooth installation process.

To successfully change your dryer’s cord, you’ll need the following tools:

  • Phillips Screwdriver
  • Standard Screwdriver
  • 3/8″ Nut Driver
  • 5/16″ Nut Driver
  • 1/4″ Nut Driver

Step 1: Disconnecting the Old Dryer Cord

Begin by ensuring your dryer is unplugged. Locate the access panel on the back of the dryer, which varies in size and shape based on the dryer’s make. Remove the cover, typically secured by 1-4 screws.

Step 2: Accessing the Terminal Block

Upon opening the access panel, you’ll find a terminal block with three wires: black on one end, white in the middle, and red on the other end.

Step 3: Removing the Existing Dryer Cord

Use the appropriate nut driver or screwdriver to detach each wire from the terminal block. Be cautious not to drop any nuts or bolts inside the dryer.

Step 4: Disconnecting the Bonding Jumper

Locate and remove the bonding jumper, which may be a metallic strap or green wire connected between the neutral terminal and the dryer’s frame. This step is crucial for preventing electrical shocks.

the bonding jumper on your dryer

Removing this bonding jumper is an extremely important step when changing from a 3-wire to a 4-wire cord to prevent electrical shocks when touching anything metallic on your dryer.

Step 5: Preparing for the New Cord

Loosen the screws at the connector and remove the old cord. Thread the new 4-wire cord through the connector, ensuring it is snug but not overtightened.

Step 6: Attaching the New 4-Wire Dryer Cord

Attach each wire of the new cord to the corresponding terminal on the dryer’s block – white to white, black to black, red to red. Connect the green wire to the green ground screw on the dryer’s frame.

Step 7: Reassembling the Access Panel

Once all connections are secure, replace the access panel cover.

Safety Tips and Final Checks:

  • Power Safety: Before plugging in the new dryer cord, turn off the breaker to the dryer receptacle. This provides an added layer of safety in case of any wiring errors.
  • Testing the Connection: After securing the new cord, plug in your dryer and then turn the breaker back on. This method is safer and helps to verify the success of your installation.

If your dryer is different from the one described above and you would like a second opinion on your connections, contact us with a picture of the terminal block. I will post the right answer on how to change 3 prong to 4 prong dryer cord to help others with the same dryer.

Conclusion

In conclusion, changing from a 3-prong to a 4-prong dryer cord is more than a simple hardware update; it’s a significant step toward ensuring the safety and compliance of your home’s electrical system. This transition addresses the inherent safety risks of the outdated 3-prong design, which combines the neutral and ground wires, leading to potential electrical hazards. By adopting the 4-prong cord, homeowners can significantly reduce the risk of electric shock and other electrical dangers, thanks to the separate and dedicated ground wire that provides a direct path for grounding.

Moreover, this upgrade aligns your home with modern electrical codes and standards set by entities like the National Electrical Code (NEC). Such compliance is crucial for safety and the resale value of your home, insurance purposes, and peace of mind. While upgrading can be straightforward for those with basic electrical knowledge, it underscores the importance of electrical safety and the need to keep up with evolving standards in residential electrical systems.

Ultimately, switching from a 3-prong to a 4-prong dryer cord represents a responsible, forward-thinking decision for any homeowner. It reflects a commitment to safety, adherence to current electrical practices, and a proactive approach to maintaining a secure and up-to-date home environment.

Mas Broto

Written by: Mas Broto

Mas Broto is a small business owner with 30 years experience in the real estate industry. He is the founder and editor of theDailyThrive.net, the most comprehensive free home improvement website on the planet!