Where should I set the day thermostat temp for max efficiency?

I’m trying to figure out how to find the most efficient method of heating our house and I’m stuck. On the one hand, I can set the thermostat at around 64 while we’re out most of the day and have it turn on to, say 72 degrees at around 4:00, so it will be comfortable when we come home. But when it’s very cold out, the heater runs for a long time in order to get our temperature back up. (We’re very poorly insulated, so the apartment gets very cold, including walls, furniture, etc., and no, we can’t insulate the place any better). On the other hand, I could set the temp at about 70 for the day, let the heat kick in periodically, and then when we come home, it wouldn’t be so hard to get the temp up to a comfortable level. How do I find the right balance? What information do I need to gather? Any help? Thanks, dopers.

How long does it take the heat the house up to your comfortable temp at the coldest weather you expect to have? It the worst it can be is 2 hours (just say) then turn the heat down as low as possible during the day and kick in two hours before you get home.

If at the coldest temp, it takes 6 hours to heat up the house from 55 degrees (a safe low temp) then you’ll have to turn the heat up 6 hours before you get home. This will cost you a lot of money since on warmer days you are spending lots of extra money to heat an empty house.

You’ll have to decide how much extra money you are willing to spend to have the house comfy when you get home, there’s not a huge amount of other info to gather.

You should also look into covering your windows with plastic, adding insulation around the doors and windows, and other insulation efforts, otherwise you are throwing money away.

The most efficient method is to drop your heat down the lowest safe (no pipes freezing, plants won’t die) temperature during the day and turn it on in time to be acceptable when you get home. If you set it so that 80% of the time it’s up to 72 when you get home you’ll probably be OK. You can wear a sweater until your furnace catches up.

Duplicate thread.