I would like to add a garage heater (Cadet "The Hot One" - 5000/3333watts - two settings)
I currently do not have any 240v access in my garage.
My main panel is in my basement and my garage is attached so if I measure from my main panel to the interior wall of my garage where the electric would feed from the main panel the run is about 22 feet - The electric heater would be mounted about 20" from the garage ceiling so the receptacle could be above or below so that would put that full run at about 25 feet.
I have a 200 amp service and currently have 9 slots available in my panel.
My understanding is the cadet heater needs a 30amp breaker, NEMA 6-30R outlet and I think I can run it with 10/2 cable.
I would run the line up through the garage wall plate and have the cable behind the drywall and run it into a metal box for the NEMA 6-30R outlet.
I am unclear if the 10/2 is sufficient, I believe it is, and then about grounding the box receptacle box.