I have a 2 story 2300 sq ft home that is on a single system (no zones). The temperature gradient between the two levels is insane unless I run the fan quite a bit. My question is , is there any device on the market to help me automate the fan so that it cycles at set times for set periods of time? I would like to run the fan for 15 minutes every hour except for the times that the house is vacant. I hope to find something like a programmable thermostat that will allow me to program my fan cycle too.