I have the Hot Dawg 75,000 LP heater in my shop. I vented it thru the side
of the shop (gabled area) to prevent any problem leak problems associated
with going thru the roof. The shop is a 28' x 36' x w/14' walls. It has
the normal 2" blanket insulation in the walls and roof area. I live in the
pacific northwest 6 miles from the Canadian border. The occasional
Noreaster out of British Columbia drop the temps into the teens for days at
a time. Normal winter night time temps run in the high 20's to low 30's.
Since I'm retired, I get to use the shop a lot. I set the thermostat at
65deg. for 10-12 hrs during the daytime. If I know it will drop into the
20's during the night, I leave the furnace at 45deg. If it's going to drop
only into the lower 30's, I turn off the heat completely.
I use 90-105 gallons of propane yearly. I have no problems with glue or
finishes freezing. I have zero problems with machined surfaces rusting.
I highly recommend this unit.