On the first chilly day we turned this small heater on. I was skeptical that it could heat a space up to 1000 square feet... but I now am a believer. Our condo is 726 square feet, and with the  heater in the living room, it heats up quickly, efficiently, and is quite quiet. We live in Georgia so we cannot speak to this heater's performance in super cold climates, but for us, it is perfect!