The house I'm renting has a very old (fire-prone) Zinsco panel. There are only 7 breakers for the entire house, and shared neutral multi-wire branch circuits all over the place.
At the moment, breaker/circuit 3 is only controlling the garbage disposal.
Breaker/circuit 4 is a GFCI that controls two receptacles (air fryer / water dispenser / electric toaster ), the dishwasher... oh, and the fridge!
NEC says shared neutrals should be on double pole circuit breakers. These are not. They're also relying on the metal box / screws as the neutral, which I don't love, but alas...
I'd love to separate some of those out, but here's my setup:
My hope was to not fish new wire or break into drywall by:
Getting rid of the button (since it controls both plugs below the sink).
Running the dishwasher into the receptacle under the sink
Installing an air switch for the disposal.
I was possibly also thinking of wiring this GFCI into circuit three (to have disposal, dishwasher, and air fryer on one circuit — keeping some stuff away from the fridge circuit).
But this setup is with the shared neutral is confounding...
I'm guessing it's something similar to this video here, but the half-voltages issue is weird. Especially since there were three neutrals connected to the GFCI plug.
I'm somehow getting measuring 60V on the wires of the switch, but it turns into 120V down below when switched.
Must be another junction box somewhere else, right? What am I missing here?