Hi, My house has a large living room about 400 sq feet with 20 ft high cathedral ceiling. In winter, heat rises and gets trapped near the ceiling and house always feels cold. I'm thinking of installing a ceiling fan to help recirculate the warm air. I'm in california so humidity is generally not a issue in summer and my house generally stays cool. So, I'll most likely use the fan more during winter than summer.

At what height should I install the fan?

Also, would a 52" fan be sufficient or do I need a bigger fan.