Furnace Question

[paceman]

To save a few bucks on the heat bill I have been thinking about getting a programable thermostat and then set it to lower temps when we are not at home and at night while we are tucked into our warm beds. The questions I have is does this actually save much as the furnace would run longer to bring the temps up when we want warmer temps and is this hard on the furnace components with constant adjusting up/down? I was thinking about having the house at 68 at night and when were asleep and then 71 when were up and home.

[BobT]

Quote:

The questions I have is does this actually save much as the furnace would run longer to bring the temps up when we want warmer temps and is this hard on the furnace components with constant adjusting up/down?

This comes up a lot with this topic but research has shown that using a programmable thermostat does in fact reduce the overall fuel consumption. With only a 3 degree change as you are thinking, it might take a while longer before you'll recoup the cost of the thermostat. Why only 3 degrees? Consider taking it down more like 7-10 degrees.

[Tom7227]

From US Dept of Energy:

Thermostats and Control Systems

You can save around 10% a year on your heating and cooling bills by simply turning your thermostat back 10°–15° for eight hours. You can do this automatically without sacrificing comfort by installing an automatic setback or programmable thermostat.

http://www.energysavers.gov/your_home/space_heating_cooling/index.cfm/mytopic=12720

Without getting overly complicated the greater the temp difference between two bodies the faster they try to reach the same temp. That means the hotter your house is the faster it looses the heat. That's why you save energy. You probably can drop it to 62 0r 63 a night and won't even know the difference. In fact you can probably have the thermostat go to the lower setting an hour before you go to bed and you won't know the difference. Have it come on maybe a half hour before you get up. You'll be happy you did it.

[spearchucker]

Ours goes to 63 at 10PM and kicks back up to 70 starting at 5:50AM. Everything is warmed up by the time we are up. It then goes back down during the day while we are at work and kicks back up to 70 at 3:00 when the kids get home from school. Between the programmable thermostat and the new furnace our gas consumption is much lower.

Your results will vary depending on your insulation, etc.

[pikechaser]

Personally I woulndt go more than 4-5 deg's at the most. How much are you saving when you have to warm the house up 10 deg's and the furnace runs a long time to heat the house up that much...thats alot to recover

[BobT]

Tests have proven that the energy required to reheat those 10 degrees are more than offset by the savings gained over an 8-hour period.

[Tom7227]

Personally I woulndt go more than 4-5 deg's at the most. How much are you saving when you have to warm the house up 10 deg's and the furnace runs a long time to heat the house up that much...thats alot to recover

Pike - if you set it back at night and turn it up for a couple of hours in the morning and then back down while you're at work you could have it down to the lower setting for 12-15 hours a day. That makes a great deal of difference. You can do the Google on programmable thermostats and find all sorts of info on the savings.

[spearchucker]

Personally I woulndt go more than 4-5 deg's at the most. How much are you saving when you have to warm the house up 10 deg's and the furnace runs a long time to heat the house up that much...thats alot to recover

I am saving a lot according to my gas bill. Also I am not dropping 10 degrees, only 7, and the house never cools down to 63 by morning anyway.