As a previous HVAC design engineer, you may want to do some of the following:
1. Use your Central Gas(?) furnace to keep the whole house at 68-73 deg. during 6am-11pm. Use the setback thermostat to 65 deg. at night. Use the Heat Pumps or other Resistance Heaters to heat the required rooms to 78 deg as required. This will use the gas as the main source (cheapest) to heat the majority of the house. The inefficient Heat Pumps will work better only to heat the additional 5 deg. The inefficient Heat Pumps are trying to heat the rest of the house even if they are in closed rooms. Inside walls are not usually insulated.
2. If you don’t have dual-pane windows, have them installed. My ’80s 2700 sf house had 27 single-pane windows. We replaced them with dual-pane low-e windows. We hardly use our Central HVAC now. We only turn on 1500w plug-in heaters in the rooms where occupied and use fans in the summer. I am thinking to put a whole house fan in this year. We don’t mind our house at 68 deg during winter and 78 deg during summer. We live in North OC where it get rarely above 90 deg.
Also, I heard they may be starting up a new show ‘The Real Housewives of San Diego’. Your wife sounds like a good candidate…
