Here’s why you need a Dedicated Circuit for the Dishwasher

fuse box dishwasher

Connecting two or more devices to one circuit may pose the risk of drawing more power than the system can handle. Therefore, the National Electrical Code requires appliances, including the dishwasher, to have a dedicated circuit with its breaker in the electrical box.

That means one circuit is used for the dishwasher only and no other device can be plugged into it. This ensures that the dishwasher can access the energy it needs without overloading the system, blowing a fuse, or tripping the breaker.

fuse box dishwasher

How much power does a dishwasher with a dedicated circuit consume at the peak?

Typically, dishwashers operate on 115-volt or 120-volt power. On average, studies have shown that a dishwasher unit uses approximately 1.5 kilowatt-hours (kWh) to run one load of washing dishes.

That is excluding the costs of the incoming water. At peak, a 1996 dishwasher can consume about 1.4 kWh while the old energy star and its new counterpart consume about 0.8 kWh and 0.5 kWh per load, respectively.

How much electricity does a dishwasher with a dedicated circuit consume?

The amount of electricity a dishwasher consumes varies depending on its design and the cycles you choose to run. Different settings for the types of dishware you load and its soil level will affect variables, including water pressure and amount, and consequently your power consumption.

dishwasher back circuit

Typically, most dishwashers use between 1200 and 2400 watts, with the average appliance consuming 1800 watts.

How thick should the dishwasher electrical wire be?

Choosing the right thickness of the electrical wire can lower the chances of the system to overheat or burn.

Since the wire thickness increase as the gauge decreases, large appliances like the dishwasher will utilize low gauge wires for better capacity. The 14/2 NM with a ground is the standard cable for your dishwasher.

You can also feed your appliance with a 12/2 NM with a ground for a 20-amp circuit. Furthermore, it is crucial to allow adequate slack on the NM wire so that your dishwasher can be pulled out and service without necessarily disconnecting it.

How to install a dishwasher dedicated circuit

Disclaimer! does not guarantee expressly or implicitly, nor take on any legal responsibility and any responsibility about the correctness, the exhaustiveness, or the usefulness of any information found in this article., as well as its usage. NEVER WORK WITH LIVE VOLTAGE. Always disconnect the power source before working with electrical circuits. When performing electrical work, ALWAYS READ AND FOLLOW THE MANUFACTURERS INSTRUCTIONS AND SAFETY GUIDELINES. Always follow your local electrical code and requirements which are specific to local areas. (source)

Things You’ll Need

  • Wire strippers
  • Screwdriver
  • Wire cutters
  • 12-gauge wire
  • Wire nuts


Turn off the electricity

ensure that you turn off the main switch before you start working. Also, turn on your lighting system to fully confirm that the main power is off.

Remove the front cover of the panel– using the screwdriver, remove the screws securing the cover door to the service panel. Set the door and the screws aside for later reassembly.

Connect the circuit to the panel

Remove a knock-out and place a cable clamp to keep tension off the wire. Strip and connect the white, ground wires to the grounding bus and the black wire to the breaker.

Typically, the breaker will fit in place making contact with the hot strip in the panel. Ensure the breaker is turned off before you connect it.

Attach the wires correctly

strip at least an inch of insulation from the ends of the 12-gauge wire that is to be connected to the breaker. Attach the bare wire to the ground strip located at the bottom of the service panel. Install the white wire to the neutral strip running down the center while the black wire to the single screw. Hold the wires in place by tightening the screws using the screwdriver.

Connect the Dishwasher

the terminals for the dishwasher connections are behind it, near the floor. The hot wire is either brass or black while the neutral is white or silver. The ground connection is usually a green screw.

You can either connect using a cable with a plug on the other end (pigtail) or using the terminals to the circuit wires in the wall (hard-wiring). Installing a pigtail requires you to plug it into a three-prong receptacle.

It entails drilling a 1-inch through the cabinet through which you will pass the plug. With the hard-wiring, you will find the circuit wires in the breaker into which the washer fits.

Connect them and place wire clamps to prevent the cable from loosening if you need to move the appliance.

Replace the door

line the panel door and punch out a knock-out slot to ensure the breaker’s switch will extend through once the door is reassembled. Replace the cover door and use the screwdriver to secure and tighten the screws.

Video instructions

Other requirements when installing a dedicated circuit for your dishwasher

If you use the wrong size of a dedicated circuit, you may trip the breaker every time you try to run the appliance. So, when planning what dedicated circuit to use for your portable or a built-in dishwasher, consider other requirements like:

Dishwasher amperage

Dishwashers have an operating load average of 13.5 amps. Hence, the amperage of the circuit should be higher than that required by the unit, preferably between 15 and 20 amps.

GFCI and AFCI requirements

Ground-fault circuit interrupters (GFCI) and Arc-fault circuit interrupters (AFCI) requirements vary from jurisdiction to jurisdiction. Typically, the dishwasher circuit needs GFCI protection. However, with the AFCI protection, you should check with your local authorities to get their interpretation of the code.

Portable versus built-in unit

A portable dishwasher requires a GFCI wall outlet while the built-in appliance that is directly wired will use the GFCI circuit breaker. According to the Occupational Safety and Health Administration, the GFCI will cut power to the device in 1/40 second if a ground fault, short circuit, or overload occurs.

Correct plug type

A dishwasher uses the 15-amps three-prong cord. The center prong is the designated ground plug that prevents electric shock from a device with loose wires or short-circuited. Moreover, some dishwashers might require special plugs like the 90-degree plug to ensure it fits into place properly.

On a final note

A dishwasher is a significant device that uses more energy than other home components. Without the right dedicated circuit, the dishwasher can overheat or trip the electrical system and possibly cause a fire.

Hence, it is crucial for the dishwasher (wired-in or portable) to have its own circuit that can handle its electrical demands and allow it to run correctly, safely, and without disruption.