I tried searching for this as I'm sure it must have been asked before, but I was not able to locate anything after lots of searching (maybe I need to work on my searching skills).
Anyway, we have a single stage furnace for our two-story home and only one zone. The thermostat is located on the first floor. Our second floor (where our bedrooms are located) gets too cold at night during the winter and too hot during the summer. What I'd like to do is add a second thermostat upstairs to control the HVAC in order to keep the upstairs warmer/cooler. I realize that I will be overheating/overcooling the downstairs but I'm willing to pay for the utility bill for the comfort of my family until we can upgrade to a better system that has multiple zones or a second unit.
Can I just wire another thermostat in series with the first one on the first floor and make sure the first one is always on when I want to control the HVAC with the upstairs thermostat? (ie, during winter nights, I would set the downstairs thermostat to 100 degrees or something very high and control the upstairs temp via the upstairs thermostat)
Are there any potential problems with this?
Thanks in advance!