On a digital thermostat what is the most efficient setting?

Question

Okay I have different cycles....

Sleeping = XX degrees
Wake = XX degrees
At work = XX degrees
Home from work = XX degrees

I have those 4 settings set for various times throughout the day, but what's the most efficient way for me to set the temps?

I had it at 70 degrees when I'm home and 62 degrees when I'm asleep or not home. My gas bill was still through the roof. A buddy of mine told me to not make such a drastic change in temps... Anyone have any really successful settings?

Thanks!

Answer 1

Sorry, but your buddy is wrong. The lower you can set it, the less it costs. Period. It doesn't matter if it has to run for awhile to heat up the house. The only reason to avoid wide swings is to minimize expansion and contraction, which is not a big factor.
I've used set-backs of 50F when I'm gone, or 55F when asleep, and it takes less than an hour to bring the house back to 70F.

If it is your house, insulate insulate insulate!! It doesn't matter how big it is, it's how fast it loses heat. (the insulation is more efficient with a lower inside to outside temp, too.)
The math says that if you insulated your sidewalls to an average of R-40, and your attic to R-60, you would not even need a furnace in Wisconsin (where I live) because the waste heat from cooking, water heating, people, washing, electronics, etc...would produce enough BTU's to heat the house.

Do it once, do it good and forget about it...then forever reap the benefits!

Answer 2

You will absolutely see a reduction in energy requirements. Your friend is out to lunch. The lowest energy consumption would come with the thermostats turned off. Clearly that is not desirable however.

Heat loss through the walls is dependant partly upon the temperature difference from inside to outside. A higher difference will cause greater energy loss. Reducing the temperature inside will lower the difference and reduce energy loss. When the thermostat allows the house to cool, energy is lost through the walls until such time as the house is at the lower temperature. This is when the savings begins and will remain until the thermostat increases the temperature again. At this time, you have to replace the energy lost during the cooling period, and then also keep up with the higher heat loss due to higher temperature. The furnace will not work any harder. It is either fully on or fully off, no in between. It will have to run longer to replace the lost heat and restore the higher temperature, but it does not work harder. This longer run period is to replace energy lost during cool down, during which time the furnace did not have to operate at all.

I have my thermostats set at 17.5C (64F) morning and evening, 14.5C (58F)overnight and daytime. If we leave for several days I reduce the settings even further and place them on hold. Thick blankets in bed, a long sleeve shirt or sweater, sometimes warm socks goes a long way to making the house comfortable. Our energy consumption is less than any of the neighbors, and much lower than the fuel company suggested for monthly budget payments. We consistantly end the year with a significant surplus.

You should perhaps look elsewhere for energy savings. Seal around doors and windows, add insulation in the attic, and put plastic shrink plastic over windows. Seal off and turn off heaters in unused rooms. Just don't go to the extreme of creating potential of frozen pipes in the house...

Answer 3

50F for sleeping and When home set at 68F and when at work set for 60F. This way will not take too much to heat up your house. Also close off some rooms you may not be using, and wear a sweater around the house. Check with you local gas company for suggestions as they will have done numerous studies and may even come to you home to do a free evaluation to save you $$.

Answer 4

Your buddy is right, because when you have it at a lower temperature, and then it goes up to 70, it will use just as much gas, because it will have to run longer to bring it back up. If you keep it around 67, then the furnance does not have to work as hard to bring it back to 70, try and experiment with it, but really you should not have such a variance in the temperature.

Answer 5

set it at 1 temp and leave it alone