I'm installing a new instant water heater. The unit requires a 6 gauge wire when there was only a 14/2 (undersized?) wire going to the previous boiler-style hot-water heater. The electric panel is in the garage roughly 40ft away straight shot through the attic.
Now I don't fuss around with the breaker panel (I'll hire an electrician for that). I mainly have two concerns. Can 6/2 wire like this be run in the wall, namely the stretch from the attic down to the heater which is in a closet and down to the breaker from the attic.
And also, do I need a subpanel? Or can the 60amp breaker be installed in the master panel and the 6 gauge wires be connected in some kind of enclosure using a 6 gauge terminal block to the conductors of the water heater?