I have bought 2 of the 14000btu heater units, and found out that during a freeze, the room has be above 45deg F for the heater to work. It says this in the manual, which i had to read when i thought the unit was broke, lol. We've not had any issues with the heater when used in the right environment, and the air-conditioner has worked well too, for over a year.
Rating: [5 of 5 Stars!]