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kris
11-24-2008, 12:14 PM
Okay, here is a relatively simple question, maybe.

Say it's 40 degrees outside, which it is. Do you really think there is a difference in setting your thermostat from 69 degrees, or 72?

I know the initial jump from 69 to 72 will cause a increase in gas consumption, but from there on out, shouldn't it be the same? I mean, the heater will still kick on to maintain the 72, just like it would kick on to maintain the 69, right?

In reality, there should be no cost difference, right? Make sense?

KapitanSparrow
11-24-2008, 12:22 PM
Don't know. But I realized last night that my heater would go off every 5 minutes when the temperatute was set to 72. When I lowered it to 69 it only went off every half hour or so.

denaliguide
11-24-2008, 12:48 PM
[quote="kris"]Okay, here is a relatively simple question, maybe.

Do you really think there is a difference in setting your thermostat from 69 degrees, or 72?

[quote]

the difference is 3 degrees. you are right it is really simple :haha:

i think it would take more energyto maintain a higher heat setting than a lower one.

rockgremlin
11-24-2008, 01:06 PM
I see your argument. Wouldn't it cost more INITIALLY to bump the temp up from 69 to 72? From there it's just maintaining the temp at 72, just like it would at 69. But the difference lies in the overall change in temp between the outside and inside of your house.

In other words, your furnace would kick on a lot more at 72 degrees because it requires more energy to maintain the ambient temp inside of your house at 72 than at 69. That's the theory anyways. Much of this discussion relies on how well your house is insulated, and how many square feet you are trying to heat.

James_B_Wads2000
11-24-2008, 02:23 PM
In other words, your furnace would kick on a lot more at 72 degrees because it requires more energy to maintain the ambient temp inside of your house at 72 than at 69. That's the theory anyways. Much of this discussion relies on how well your house is insulated, and how many square feet you are trying to heat.

I think rock is right on this. The greater the temp difference between the inside and out the more energy is required. I think that makes sense to everyone. But if I have my heat transfer theory correct, the amount more it takes to heat more is not directly proportional to the increases of the temperature difference between the inside and outside. In other words if you double the temperature difference between the outside and inside you will have to more than double the amount of heat needed to maintain that higher inside temp, therefore the increased cost would be more than double.

I hope that makes sense. :ne_nau:




James

Mtnman1830
11-24-2008, 03:20 PM
What I do probably isn't any more cost effective, but I turn my thermostat up to 70 sunday morning when I get my son.

Wendsday night, I turn it down to 65.

Then again, I work graveyards and all I do when I am home is sleep.

BruteForce
11-24-2008, 04:10 PM
I have a programmable thermostat (digital). When we're sleeping and during business hours, it sits at an average of 64F (keeps the dogs/cat/fish comfortable). When we're home (after hours), it kicks in to 70F.

At night (10pm), it drops down to around 68F.

Our fuel bill in the winter is pretty consistent.

Sombeech
11-24-2008, 04:28 PM
It's all specific to your house.

Say you set it at 50 degrees in the winter. The heater first has to fire up, then the blower comes on. 50 degrees is reached, and then the flame goes out. The blower still stays on for the same amount of time after the flame is gone, just to get the hot air out of the furnace.

It also depends where your thermostat is in relation to the vents. The mercury is inside of the actual control box, so if it's right over a vent, it's going to tell the heater to shut right off, while the rest of the house isn't at the desired temp.

So if your thermostat is pretty far away from the vent, the heater will stay on longer until the wave of warm air reaches the thermostat.

But now regarding the difference between 72 and 69...

It is more efficient to go lower, because once 69 is reached, the flame goes out, but the blower still remains just to get the air out of the furnace, so you'll rise a little above 69 just from the leftover air.

Scott P
11-24-2008, 04:58 PM
Do you really think there is a difference in setting your thermostat from 69 degrees, or 72?

It varies with temperature, house and furnace, but the difference is huge. Above 68 degrees, plan on a 5-10% increase in gas usage for ever degree the temperature is turned up.

Now that we have kids, we keep our house 67F in the day and 60F at night.

kris
11-24-2008, 10:44 PM
Lot's of interesting points. Gives me a few things to experiment with. Thanks! :rockon: