We recently bought a 1978 home in Florida.
The kitchen wiring leaves me scratching my head. I think I have solved 2 of 3 major problems, but need advice on the last.
4 different 20A tandem breakers in play. One of them was split into 2 INSIDE the breaker panel, one was split in a gang box so I am dealing with 6 "hot" wires & only 4 neutral wires.
1) 12/3 Romex. Black/neutral on one breaker [16 L] leads to kitchen GFCI outlet --> regular outlet --> kitchen light switch --> kitchen light. Red "hot" [14 L] leads to light (former fan) in living room with light fixture neutral connected to neutral wire from the kitchen breaker.
To solve the shared neutral problem, we disconnected the living light and connected it inline with the living room outlets using 12/2.
(The kitchen light is downline from a GFCI which isn't ideal but I don't want to mess with what works.)
2) Breaker 16 L splits inside the breaker box with a hot single black wire through conduit to the other side of the kitchen. That wire powered the microwave, dishwasher + 2 outlets and had NO neutral. (Neutral for this breaker is on other side of room in the 12/3.)
In that SAME conduit are a hot/neutral from breaker 14 R. This was used to power the garbage disposal through an under-sink outlet. The neutral from 14 R was then wired up from the disposal outlet & connected to ALL of the other appliances/outlets on 16 L.
To solve this shared neutral, we 1st removed the microwave and put it on it's own 20A circuit.
Next thing was to disconnect everything & wire the 14 R breaker from dishwasher outlet ---> disposal switch ---> GFCI under-sink outlet.
3) That leaves us with 2 outlets adjacent to the sink with power but no neutral.
Would it be better to splice in a neutral wire from one side of the kitchen to the other. There is a junction box directly above, so it should be fairly easy.
Would it be better to remove the splice on 16L inside the breaker box and run a whole new 12/2 to the sink outlets?
My concern splicing a neutral is with using GFCI outlets and having the same neutral run through GFCI outlets on both sides of the room. Would that cause problems?
My concern with running new wire is using up 4 breakers just for the kitchen.
Thanks for any advice!