Received my G73 heater in 2 days. I'm liking the Prime Membership, well worth $79.00 a year. I have a 220v A/C unit in my garage, rated at 20 amp. I didn't want to run any more wire to use this heater, I did purchase it and realized all the post about running 10/2 with a ground and a 30 amp breaker. Well we took the electrical cover off the back, the heater is wired with 12/2 with a ground so we tried it for a couple of days now and it hasn't tripped my 20 amp breaker. I have 12/2 with a ground run, it's about 50' to the breaker box. I bought a Utilitech 12 gauge A/C plug from Lowe's, Model # 0051659 which is the same male plug as my A/C unit, the other end is female, I cut that off to run to the G73. Thermostat is all the way and not tripping the breaker and the wire is not even warm. It's 37 degrees outside and it's 78 degrees in my garage right now, fixing to turn it down a bit. My garage is 24' x 24' insulated. garage door is insulated also. Hope this helps anyone with questions about wiring. Also the Utilitech plug I bought, on the package is 12/3 SPT-3, 20A-250V-5000W.It's December 18th, still running the G73, only after work and on the weekends. I was debating putting a switch, but I don't think my garage gets that cold. From what I understand the lowest setting on the thermostat is 45 degrees, my garage might get to 50 degrees if it's really cold. Running about 4-5 hours a night, still hasn't tripped my 20 amp double breaker, wire still doesn't get warm. My 12/2 wire run to the garage is about 60' from the breaker box also. I'm not saying this is the way to do this, already had someone tell me I was stupid, but it's never unattended and I don't use it often.Update 12-10-14Second year using the G73 heater, had a problem with it and contacted NewAir,a connector broke off inside the heater. A new heater was sent to me in less than a week. All is good, great customer service.