Is it possible and safe to have a garbage disposal on the same circuit as your dishwasher?
Before answering this question, I need to be clear that you should consult the help of a licensed, professional electrician, as well as the building codes for your particular locality. These codes will vary between states, towns, and counties, so be sure you're clear on what is permissible from a code perspective before moving forward.
A good electrician can help you with this aspect as well.
But for informational purposes, I'm going to answer this question here so you can plan your wiring going forward.
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Can a dishwasher and garbage disposal be on the same circuit?
If you want your dishwasher and garbage disposal to run off the same circuit, you need to make sure you're using a 20-amp circuit, as opposed to a 15-amp circuit. Here's a close up look at a 20-amp circuit breaker:
You'll also need to make sure the total amperage of the two appliances combined does not exceed 80 percent of the circuit amperage rating. Most dishwashers are around 10 amps, with garbage disposals significantly lower, which means you're unlikely to reach that 80 percent mark.
Here's a reference for some dishwasher models and their typical amperage rating.
Though this is a good question to ask your electrician as it can vary depending on which two models you're trying to combine.
The More Ideal Scenario
Despite the fact you can share a 20-amp circuit for your dishwasher and garbage disposal, it's definitely not what I'd consider an ideal scenario.
In most cases, a dishwasher should have a dedicated 15-amp circuit.
This is also recommended by the International Association of Certified Home Inspectors.
My preference: Have the garbage disposal on its own dedicated 15-amp circuit as well, unless you have a 20 amp circuit with room to accommodate. But in most cases, a dishwasher is already going to be wired in with a 15-amp dedicated circuit. Instead of swapping the 15 for a 20, just add another 15-amp circuit, dedicated for your garbage disposal.
Always be Open to Suggestions
This is of course contingent on having your electrician sign off on the work. Even if you're doing the work yourself, it's a good idea to confirm the changes you're making with a professional. Chances are, they'll recommend a 15-amp dedicated circuit for both appliances. Just be open to suggestions, if there are any.
To summarize, I'd recommend a dedicated 15-amp circuit for both your dishwasher and your garbage disposal. If you already have the dishwasher on a 20 amp circuit, check your amperage ratings for both appliances and see if you have enough headroom to add the garbage disposal onto that circuit as well.
If you have questions, feel free to drop those in the comments section below and we'll jump in to help out as best we can.
We'll see you there.