A house that already has central AC shouldn't need any significant of electrical changes. My rental house in Sunnyvale,CA I just converted to a Mitsubishi central heat pump there two small electrical changes for it. The breaker was reduced (I guess some inspectors are sticklers for making it match the plate rating). Electrically this was not needed since the wire was sized for the previous larger drawing unit. The second thing that we had to was add an 120V electrical outlet within 25' of the outdoor unit. Apparently this is a code requirement. I'm guessing to make it easy for future HVAC people to service the unit.
Put another way, if you have central AC and you are looking to replace it (for whatever reason), you should seriously consider a heat pump. In some cases you can keep your existing gas furnace as the air handler and for backup heat.
Put another way, if you have central AC and you are looking to replace it (for whatever reason), you should seriously consider a heat pump. In some cases you can keep your existing gas furnace as the air handler and for backup heat.