How to Install a 4-Prong Range Cord

Depending on when your home was built, it would have either a 4 -prong or a 3-prong wiring system. However, if you are moving to a new home with 4-prong receptacles and you have a three-prong electrical range, you will need to install a 4-prong range cord to accommodate the required range wiring. 

In this article, RG Electric will explain how to install a four-prong cord. The good news is that the process is very simple and takes only 15 minutes. However, before we dig into that, let’s look at the difference between the two wiring systems, why you need to install a four-prong range cord, and the advantages of a four-wiring system.  

4-Prong Receptacles and 3-Prong Receptacles

You might be wondering about the difference between the two types of receptacles. Here is the point. Homes with three-prong wiring have receptacles with three prongs – two on the side are hot wires, and one below in the center is a neutral/ground wire.    

Houses or apartments with four-prong wiring have receptacles with four prongs – two hot wires and two separate wires for ground and neutral. 

If you look at your three-prong range (in the terminal block), you will see that a wire in the middle, the neutral one, is connected to a ground strap; thus, one neutral wire provides a grounding path through this strap. But a four-prong cord has a separate ground wire, which is green. 

Why You Need it

NEC’s (National Electrical Code) requirement from the 1996 edition affects electric ranges and clothes dryers. In a nutshell, it says that homes must have four-wire circuits for these appliances. Yet, it also allows using three-wire cords because many people still live in older homes. 

If you are moving to an older home and have a four-prong range, you should never attempt to change the range plug to connect it to a three-prong wiring system. In this case, you have to rewire your range to a three-prong cord. 

• The rule of the thumb is that if your house has four-wire receptacles, you must install a 4-wire cord. And if your home has three-prong outlets, you must install a three-wire cord.  

NEC dictates that homeowners use a 4-prong wiring system because it is safer than 3-prong wiring. There’s less possibility of electrocution or electric shock with the four-prong wiring system. So it is considered much safer.        

Step by Step

Most ranges and dryers at stores come without cords because homeowners may have either type of receptacle. After you buy a 4-prong cord, here are the step to install it:

• Turn off the circuit and unplug the appliance;
• Locate the terminal block on the back panel of the range;
• Pop the metal cover off to get to that;

You will see black, red, and white wires if you have an old three-prong range. With four-prong range cords, you got four wires: black, white, red, and green. Black will go where the black is, white where the white is, and red wire where the red is. As for the green one, you will see a bridge that connects the white wire to the frame on the terminal box (for three-prong ranges), thus grounding it. 

• Unbridge this; 
• Remove the bridge (the strip);
• Disconnect the old cord by pulling each end of the wire (if you have an old range);

Important: If you fail to remove the strip, the range won’t be grounded correctly, resulting in a shock.

• Connect the green wire to the green screw or the ground screw on the range body;
• Have the clamp put in place to secure the cord;
• Pull it through and secure;
• Pop the wires off on the terminal box;
• Once they are all out, start connecting the wires; 
• The red cord slides into the red side or to the right, secure and tight it;

The green wire should be connected to the spot where the bridge was unscrewed. 

• So insert it there and pop it on. Use the screw to tighten it down; 
• The next thing is to attach a white wire to the center;
• Finally, connect the black wire to the black cord or the left side and also tight it;

As for the bridge, you can choose to bend it away or remove it if you want. 

• Tight down the clamp, holding the 4-prong power cord.

Need to Install a 4-Prong Range Cord? Contact RG Electric

Our licensed and trained electrician crew in LA Metro Area can assist you with any electrical upgrades. We’re equipped with the right resources to provide safe and high-quality wiring services.