I just installed a Mr. Heater Big MAXX 45000btu in a 400 sq ft work shop. I vented it out of the back. Worked great! Only needs 1" clearance from the ceiling.
Ordered my Mr. Heater on Friday. Should arrive by 9/10, 45,000 BTU. I'm using it to heat a 384 sq. ft. detached workshop. Did any installation hardware come with the unit?