First time Ive ran across this type of configuration.
House had a pretty new air conditioner and heater wired
to it…Should I recommend upgrading to a newer panel ?
the old HVAC most likely was less energy efficient meaning the old system had bigger wires and bigger breakers. just make sure the existing circuit and breaker are a match for the HVAC system and let it ride
I would call it out for replacement do to the age of the thing. When I see old stuff it need service if nothing Else. just pulling the thing apart and looking in on the back side is a good idea. then checking every connection for the correct toque. its just filthy inside.