[ZinscoMan]

My residence has 1970 Zinsco main panel outside and branch panels inside. The outside main panel already has 8 double breakers and no main disconnect. So to replace my central A/C I must change out a switch (because my old blower is on 115V inside and the new air handler requires 220V and the inside panels don't have breakers that can be tied together to make 220V switch. The outside main panel breaker for A/C is 30 amp and needs to be 40 amp for the new A/C because it would now control both condenser and air handler with 220V UF wire from new air handler running down side of house to new subpanel replacing old fuse box for condenser. I'm told I must replace the entire outside main panel box (and add main disconnect) and need AFCI and GFCI breakers to meet code.

(1) Can I only replace the outside main box and breakers which then become AFCI or GFCI or dual and leave my inside branch panels as they are since the A/C technicians wouldn't need to touch them anyway? (Inside Zinsco branch panels in good condition, standard thermal breakers.)

(2) One kitchen circuit has two wall receptacles on it, one on a countertop and the other a wall receptacle for the refrigerator. I'm confused since the countertop needs GFCI but the refrigerator wall outlet cannot have GFCI because the manual says so. Do I have to split these two receptacles to separate circuit breakers instead of keeping them on the same 20 amp inside panel breaker? (Or does this only apply if I were replacing inside branch panel since I'm only needing to replace the 70 amp switch the entire branch panel is on in the outside main panel?)


(3) If I keep my inside Zinsco thermal non-AFCI, non-GFCI breakers and only replace the outside power box, can the new outside 70 amp breaker be AFCI only (because of the refrigerator not allowing GFCI)? Is the GFCI requirement only for the circuit breaker closest to the appliance (inside panel which the A/C technicians wouldn't need to mess with) or does the GFCI requirement travel from inside panel to outside panel breaker type?

More information below:
Inside branch panel 1: 16 single pole (115V) switches, either 15 amp or 20 amp each all go to outside 70 amp switch (numbers on switches add up to 290 amp)
Inside branch panel 2: 14 switches (some double and some single), either 20 amp single or two 20 amp tied together all go to outside 70 amp switch (numbers on switches add up to 280 amp)
Outside main panel: 8 double pole switches and no main disconnect (numbers on switches add up to 235 amp)

Morty,
North Carolina

[hfcarson]

Morty,
After a quick read of the NC Rehabilitation Sub-code, you should be able to replace your exterior main service panel without doing any of the other items you have listed.
You will need to install a new panel with a main circuit breaker.

A strongly recommend you contact the local electrical sub-code official or inspector and discuss the new main panel and other electrical conditions you have. I try to make myself available when my clients seek advice and as a public servant so should he.

Ask for his help, take out a permit, have your work inspected, maintain your homeowners insurance in the process, and keep yourself safe.