Need help with the thermostat to use the heater?

Ur shits backwards and ur wife is right. Ur wife will always be right.. Best get used to that now.

the thermostat turns the heater either on or off. does this based on the temp you are asking for. a lower setting on the thermostat will make the home cooler, warmer=warmer. HOWEVER, you are playing with it too much. you have a thermostat with a "heat anticipator" and a furnace designed to work with a thermostat not equipped with one. go to your favorite hardware store, get a Honeywell digital thermostat. FOLLOW the instructions, (starting with un-plugging the furnace) this is a DIY or you can call a heating contractor. install your new thermostat. start with a heat setting say, 68, and leave it there for 24 hours. see if the house is comfortable , if not, go up or down 2 degrees, wait 24 hours, (unless extreme un-comfort then 4) once found, then keep it at that setting for the winter. the thermostat is based on what we call a 2 degree "dead band". this means it will run the furnace until the temp you are asking for (set at) matches the temp in the home. then it tells the furnace to shut off. when the thermostat sees the temp in your home is 2 degrees lower than you are asking for, it will tell the furnace to come on. that is its job in life. replace the batteries with energizer around the 4th of July and again around Christmas. Replace or clean your air filter every month when you get your electric bill, this will ensure proper air flow to heat the home more even and efficient. shop your local contractor for coupons/specials for a tune up every few years. your wife is correct in a properly working system.

senior service tech, 27 years HVAC tech.

Heater thermostat has hold temp bottom ,which after adjusting temperature on 75 degree you need to push the (hold temp bottom) to temperature set on that point .That mean when home temperature is reach the 75 degree heat will shot down automatically. If you not push that bottom ,thermostat will act in to latest set temperature ,how ever you enter the new setting .

Well, your wife would be right if lowering the thermostat makes it less hot.

If it gets more hot, then I don't have an answer.

You should turn it to a lower number