What am I doing wrong? Thanks for any help.
Location: South Carolina. Normally 50* in winter, occasionally 30* on cold nights.
House: 3200 sqft, 2 story. Dual system. Registers and thermostats are both upstairs and down, and are near the stairwell.
Upstairs: heat pump, large A/C unit
Downstairs: Gas heat, small A/C unit
In summer, everything works well. Upstairs gets a little hotter despite having the larger A/C unit (larger sqft upstairs with FROG, and heat rises), but generally acceptable.
During winter, I set the downstairs to 67* to run gas heat and set upstairs to 62* so it is basically off. Upstairs thermostat reads 68* because of heat drifting up stairs. Some heat comes through floor, but not enough on cold nights. If I turn on upstairs fan to circulate the gas heat drifting up the stairs, the bedroom (62*) and bathroom (58*) still stay very cold.
What do I need to do? Should I turn down the gas downstairs and run the heat pump upstairs more? Should I even run gas given the relatively mild winters? Should I tailor based on the outside temps or night vs. day? Thanks.