I have what you would call a “mini kitchen” set up in my house for a guest bedroom. Ran all new electrical for it and hooked it up in the outside fuse box. It’s a 20 amp fuse running 4 15 amp duplex receptacles. I have a large mini fridge (always running) a large window unit (rarely ever on while cooking) a toaster oven, hot plate, and 1100 watt microwave. Not all the outlets are even being used but if I use more than one cooking device (with the fridge constantly plugged in) it blows the breaker. Since I’m running all these appliances (not at the same time but sometimes I do) can I switch the 20 amp breaker to a 30 amp breaker? I’m tired of blowing a breaker everytime something is cooked in there. Also the wire is 14/2 if that changes anything. Someone please help. The “mini kitchen” is used almost daily.

  • 15
    The 20A breaker on the #14 wire is already about to start a fire. By the way, cooking in the rooms is how a lot of (for the homeless) residence hotels burn down. May 27 at 2:53
  • 21
    I have what you would call a "mini kitchen" - I don't think you should be putting words in people's mouths at this moment. You have what I would call a "fire hazard" and you are attempting to promote it to "guaranteed fire".
    – MonkeyZeus
    May 27 at 12:17
  • 5
    Why is the guest bedroom being used daily for cooking? Are you doing an Airbnb or something? Are you trying to kill your guests via fire and lose your home?
    – MonkeyZeus
    May 27 at 13:54
  • 6
    Switch everything off, until you've had a professional electrician deal with the issue. You've been quite fortunate not to have set your house on fire already. And the nature of your question suggests that you don't know enough to be able to fix this safely yourself. Don't mess around when it comes to electrical stuff. You need a professional. May 27 at 22:45

Since the wire is 14/2, the breaker feeding it must be 15A.

Someone apparently changed that to a 20A breaker (presumably because they were sick of constant breaker trips every time they attempted to use two heat appliances at once). Since that was done, you have the sense of "hey, do it even more".

That "end justifies the means" POV ignores the reason we use circuit breakers in the first place, which is to prevent house fires. The National Electrical Code specifies this based on hard data, and if you're not interested in following that, then this is the end of the answer for you. We can't help you on this site.

Your loads and why they are tripping

A 15A circuit (which you do have, even if it's horribly misbreakered) can accommodate 1800 watts.
A 20A circuit on #12 wire can accommodate 2400 watts.

  • Your refrigerator needs about 100 watts (trivial, don't need to give it too much thought).
  • Your air conditioner needs 500-1500 watts (whatever its nameplate says; it may be stated as VA).
  • Your toaster oven needs 1500 watts.
  • Your hot plate needs 1500 watts (some are less).
  • Your microwave needs ~1200 watts.

As you can see, you can run precisely one of these at a time on a 1800 watt capacity circuit (and you get to ignore the refrigerator). A 15A circuit can't handle two.

And you know a second thing: a 20A (2400 watts) circuit can't handle two, either. So bumping the breaker to 20A didn't actually buy you anything useful, it only brought 600 more watts, and that's not enough. Since the 20A breaker is illegal, dangerous and useless, change it back to 15A.

And I bet you didn't know any of this, and were just confused and frustrated by all the breaker trips.

Now, you can make a decision whether you can live with one at a time (refrigerator not mattering) or whether it's worth the blood sweat & tears to bring more power to this room.

More power, please

For a modest power increase, I would bring up 12/3 cable, and wire it as a multi-wire branch circuit. This will yield two 20A circuits (2400 watt each). As we already established, you still can't run 2 things on the same circuit, except,

  • the refrigerator is no problem and
  • if the A/C is small, say, under 900W, then it can share a 20A circuit with a 1500W appliance.

So now, we can run the A/C, refrigerator and any two cooking appliances.

Bigger please? OK, run two multi-wire branch circuits, for four 20A sub-circuits. Everything at the same time, win!

Bigger still? OK. We'll need a subpanel. The next size up of wire is 10/3 which will give us 7200 -- oh heck, for the same price you could buy 4-wire #2 aluminum for 21,600 watts! Or for less money, #4 aluminum for 15,600 watts, or even cheaper #6 Al for 12,000 watts.

Now your subpanel will have power to spare, and you can give every appliance a dedicated circuit and use them all at once if you want to.

Both options are complicated and require a lot of knowledge, attention to detail and respect for the electrical codes, so best to hire a professional for the job.

  • 1
    Well, the 20A might have the perceived "useful" effect of actually letting you run the toaster and the microwave together for a short while, because its thermal trip won't kick in before you're done reheating your dish. Still a great way to start a fire in the walls one day.
    – TooTea
    May 27 at 13:53
  • Don't forget that if you go the sub-panel route you need to make sure you put it somewhere with suitable access space. May 27 at 14:27
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    If this has been used extensively, there's going to be damage all over the place. Melted outlets, melted insulation, burned wires, oxidization due to excessive heat, warping metal, arcing due to melted/warped outlets, etc. It's a giant hazard even if the breaker is switched back to a 15A.
    – Nelson
    May 27 at 18:08
  • 1
    @Joshua but the fridge is only 100W (throw a Kill-a-watt on yours and see for yourself) so it would fit with one 1500W appliance on a 15A circuit. May 27 at 19:34
  • 1
    +1 The other thing that may have allowed OP to "overload" the circuit somewhat is that the toaster oven and hotplates will not run at 100% demand all the time (unless on MAX or broil setting) - they will duty cycle on and off, generally (though some may use zero-cross or phase control). In any case, the time-average power draw from a 1000W hot plate will not always be 1000W. Even the microwave will duty cycle at less than max power. Depending on the power settings and the phasing of the random cycling, the same activity may or may not trip the breaker depending on luck and circumstance.
    – J...
    May 28 at 17:34

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