It was a lot bigger than expected but the room it's in is quite big, it's just trying to find somewhere to put it! I assume it's doing a good job, certainly feels cooler, so might be better in the summer rather than winter as would be counter productive with the heating on. I've timed it to go on for a few hours over night when the heating is off. If you're in the room with it then night mode or no. 1 is best. No. 2 is noisy.