I can’t seem to have the temperature in my house at a comfortable level. My thermostat doesn’t make a difference in the amount of heat produced. I think that my furnace decides how hard it feels like working that day, and that’s the level of heat I get. Some days and nights, my house is so hot, that I spend my full day sweating profusely. I am always tempted to open a windows, but I don’t want to waste my costly air. My temperamental furnace costs a lot of money to operate. After a day of too much heat pumping out the numerous vents, the following day might bring an outright tepid whisper of air. On those days, I can crank the thermostat to around ninety degrees, and my furnace won’t cooperate by any means. It would be nice if my furnace would be aware of the outside temperatures. I would be very happy if it would create scorching hot air on sub zero winter days. It is not as enjoyable when the furnace isn’t in a mood to work, even though it’s the coldest night of the calendar year. I’ve had the old HVAC system professionally serviced, and I’ve changed the very filter that it uses. Nothing improves the overall performance of my ancient heater. I would be glad if the system fails. It’s so old that it qualifies as an antique, and should be displayed in a museum somewhere. I’ve considered installing a fresh, smart thermostat, to try to acquire control over my indoor temperature. I don’t think the old furnace would cooperate with me using a modern thermostat. My new thermostat would be as powerless to run the furnace as we are.