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The key question is whether you have an overloaded Multi Wire Branch Circuit (MWBC) or a big dangerous mess.

A MWBC uses two hot wires on different legs with a shared neutral. This gives you 20A x 2 safely. If they are on the same leg but different breakers then it is unsafe because you could have 40A (if balanced between the breakers) on the neutral without a breaker trip, so that is not a valid MWBC but can start out as a valid MWBC that gets reconfigured incorrectly.

And there is a third scary possibility. Somebody takes the two hots of the MWBC and combines them on one breaker. That isn't so unsafe (because neutral can't get overloaded without hots getting overloaded and tripping the breaker) but can lead to nuisance trips (which may be what is happening in your situation).

Take a look at the breakers for this circuit:

  • Two breakers on separate legs (240V between them) - proper MWBC and you are having actual overload and need to move some appliances or receptacles to another circuit
  • Two breakers on same leg (0V between them) - bad MWBC and you need to move one hot/breaker to the other leg. Since it is a MWBC must be breakers next to each other, double breaker or handle tied
  • one breaker with two hot wires - split to a proper two breaker MWBC.

If you have a proper MWBC then the problems are likely the combination of:

  • Microwave
  • Toaster
  • Air Fryer

Each of those could easily use 1000W or more, and 2,400W is the limit on a 20A circuit. If they are all 3 on the same hot then that is a guaranteed problem and rearranging things will help. MWBCs can be wired a bunch of different ways. One common way is one hot on the top receptacle and the other hot on the bottom receptacle of several duplex receptacles. If that's the case then it should be easy to rearrange things. However, an MWBC can also come in to a box and split at (or even before) the first receptacle, so it can be hard to figure out what's what without taking off cover plates to check the wiring.

The key question is whether you have an overloaded Multi Wire Branch Circuit (MWBC) or a big dangerous mess.

A MWBC uses two hot wires on different legs with a shared neutral. This gives you 20A x 2 safely. If they are on the same leg but different breakers then it is unsafe because you could have 40A (if balanced between the breakers) on the neutral without a breaker trip, so that is not a valid MWBC but can start out as a valid MWBC that gets reconfigured incorrectly.

And there is a third scary possibility. Somebody takes the two hots of the MWBC and combines them on one breaker. That isn't so unsafe but can lead to nuisance trips.

Take a look at the breakers for this circuit:

  • Two breakers on separate legs (240V between them) - proper MWBC and you are having actual overload and need to move some appliances or receptacles to another circuit
  • Two breakers on same leg (0V between them) - bad MWBC and you need to move one hot/breaker to the other leg. Since it is a MWBC must be breakers next to each other, double breaker or handle tied
  • one breaker with two hot wires - split to a proper two breaker MWBC.

The key question is whether you have an overloaded Multi Wire Branch Circuit (MWBC) or a big dangerous mess.

A MWBC uses two hot wires on different legs with a shared neutral. This gives you 20A x 2 safely. If they are on the same leg but different breakers then it is unsafe because you could have 40A (if balanced between the breakers) on the neutral without a breaker trip, so that is not a valid MWBC but can start out as a valid MWBC that gets reconfigured incorrectly.

And there is a third scary possibility. Somebody takes the two hots of the MWBC and combines them on one breaker. That isn't so unsafe (because neutral can't get overloaded without hots getting overloaded and tripping the breaker) but can lead to nuisance trips (which may be what is happening in your situation).

Take a look at the breakers for this circuit:

  • Two breakers on separate legs (240V between them) - proper MWBC and you are having actual overload and need to move some appliances or receptacles to another circuit
  • Two breakers on same leg (0V between them) - bad MWBC and you need to move one hot/breaker to the other leg. Since it is a MWBC must be breakers next to each other, double breaker or handle tied
  • one breaker with two hot wires - split to a proper two breaker MWBC.

If you have a proper MWBC then the problems are likely the combination of:

  • Microwave
  • Toaster
  • Air Fryer

Each of those could easily use 1000W or more, and 2,400W is the limit on a 20A circuit. If they are all 3 on the same hot then that is a guaranteed problem and rearranging things will help. MWBCs can be wired a bunch of different ways. One common way is one hot on the top receptacle and the other hot on the bottom receptacle of several duplex receptacles. If that's the case then it should be easy to rearrange things. However, an MWBC can also come in to a box and split at (or even before) the first receptacle, so it can be hard to figure out what's what without taking off cover plates to check the wiring.

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The key question is whether you have an overloaded Multi Wire Branch Circuit (MWBC) or a big dangerous mess.

A MWBC uses two hot wires on different legs with a shared neutral. This gives you 20A x 2 safely. If they are on the same leg but different breakers then it is unsafe because you could have 40A (if balanced between the breakers) on the neutral without a breaker trip, so that is not a valid MWBC but can start out as a valid MWBC that gets reconfigured incorrectly.

And there is a third scary possibility. Somebody takes the two hots of the MWBC and combines them on one breaker. That isn't so unsafe but can lead to nuisance trips.

Take a look at the breakers for this circuit:

  • Two breakers on separate legs (240V between them) - proper MWBC and you are having actual overload and need to move some appliances or receptacles to another circuit
  • Two breakers on same leg (0V between them) - bad MWBC and you need to move one hot/breaker to the other leg. Since it is a MWBC must be breakers next to each other, double breaker or handle tied
  • one breaker with two hot wires - split to a proper two breaker MWBC.