Please forgive me while I troll for a moment.....
Is it energy saving to turn the thermostat down, when leaving the house? I mean, the furnace has to run to catch up when I get home. I have a way of looking at the matter. I'll explain my point of view after the argument is underway.
Yes, you save energy turning it down. In balance less heat is lost.
To elaborate, heat loss slows as the house cools (delta T is lower) so it takes less energy to maintain the house at a lower temperature and then heat it back up again. Especially so if the house is not well insulated.
That said, I have not noticed any drop at all in my gas bills since installing a programmable thermostat :(
nate
Well, according to the message I have gotten several times from Oklahoma Natural Gas, turning down the thermostat 10 degrees for
8 hours per day will lower your bill by 10%. I'm not sure the bill itself will go down that much since part of the bill is a fixed rate operating cost, but the usage part should drop. And if you can't believe the gas company who can you believe.Bill
No, it takes too long to re-heat the boiler and all the water in the pipes, radiators, and floor tubing. It is always best to set it once and leave it there all winter. Too much energy is lost when all that water is asked to re-heat all the surfaces again. For example when I feel the return manifold from the coils under my concrete slab after the slab was allowed to cool, the return water is ice cold, all that energy to reheat the slab. No, bad asvice, best to keep it warm and leave it there, saves tons of energy.
Hi, Of course. You set it back for sure.
I think it would depend on how long you are going to be out of the house. I wouldn't turn it down if I am only out for an hour but if your are going to be out for 8 hours it might be a good idea.
David
In terms of saving energy, the energy savings start as soon as the house cools to the point that the heat would have come on had it not been turned down. From that point on, you are saving energy. Whether it makes enough difference to make it worthwhile depends on how long it's turned down for.
If you turn it down to 62 overnight instead of 72 and it's 25 outside, no question you are saving energy and that gas company estimate of about 10% sounds in the ball park.
As someone already pointed out, the governing factor here is that the rate of heat loss is directly proportional to the temp difference between inside and out, at least excluding the heat loss due to actual air leakage.
The only other issue that comes into play would be if there are differing energy costs or different fuels involved. For example, if you had a heat pump and electricity costs less at night than in the morning, then that could easily negate the effect. Or if when you set it back, in the morning a different fuel source kicks in during recovery, etc.
We use warm water here to shower. I'd say that a higher % of people use heat pumps or gas to heat rather than water. In your case, MAYBE it is cheaper to leave it on, but I think you are only quoting yourself, and no analytic studies by any testing agency. Can you find any said studies? I don't doubt that you believe what you say is true, I just think that it is not.
Steve
My experiments say yes. We have 3 zones, and 2 are on setback thermostats, these 2 parts of the house are the least used, so I use extreme setback down to 50 on heat and up to 90 on AC. Still when we use them the unit has kicked on so no inconvenience except on the occasional trip through during the setback. My savings are well over the 10% mentioned, and my propane man is getting upset, hardly worth the stop anymore. (125 gal Feb thru October, mostly used to cook, heat water, dry clothes. My electric bill is also down over 1/3. I started this when energy prices spiked last year, and it has worked so well I will continue. It takes a lot of BTUs to get a room to room temperature after an extreme setback, but apparently not as many as keeping it there.
I hope that you were just kidding because obviously you are wrong! Just think for a minute.....if you were going to be gone for three months don't you think you would save energy if you turned your thermostat down? Well, the same would be true for a few hours, just not to the same extent.
OK, let's have that point of view now.
Poll question:
How many guys here have wives who mistakenly think that when warming up a cooled down house the rate of temperature increase of a typical home heating system will be faster if they shove the thermostat setting all the way up to 90F than if they just move it to the appropriate setpoint.
Then of course they forget to reset it when the place reaches a comfortable temperature and wait for the man of the house to snarl, "Why the hell is it so damn hot in here?"
And visa versa for A/C of course.
It can't just only happen to me.
Jeff
PS, I realize there may be some HVAC systems which don't conform to the above scenario, but they sure aren't in the majority around here.
Yes, if I turned it down and left it there for a week or longer maybe.
But downturning for any period under a couple days and all the mass you've spent heating once, now you have to re-heat over again. (my system has several thousand feet of water tubing under both house floor and garage slab zoned).
It might be different if you have forced air heat, but for water heat (via radiators or radiant tube) every installer tells you "set it once and forget it, the idea is to store heat".
Boiler installers never put daily "set back" thermostats on boilers, only forced air systems get those, and they tell you to set the thermostat once and leave it there.
The rules are completely different for radiant heated buidings vs air heated buildings.
In an air heated building you heat the air, in a radiant heated building you heat the building materials and that in turn heats the people. When you lose all that stored energy it costs a fortune to recover it back in boiler usage. There is nothing quite like the warmth of a radiant-heated house.
Is this for forced air furnace or boiler?
Heh.
Do you have any tips for properly instructing a user of a vehicle with an automatic climate control system?
I *hate* getting in my old Porsche and driving along merrily and then suddenly realizing that I'm sweating my cojones off. Takes me a while to realize that the "thermostat" has been cranked up to some ungodly temp. because when I was driving the car daily I think I maybe touched the control twice a year...
nate
The whole question and some of the answers, demonstrates the generally poor knowledge of basic physics. Maybe that's our education system?
No wonder the Russians got a satellite into space first? . Obviuosly if the temperature of the inside of a house is lower there will be less heat lost to outside. Because that's where it goes folks! From inside the house to outside. Higher winds also help to conduct it away.
If one left the house for a solid month with the heat turned to minimum (or off, provided nothing froze up!) less heat would be used. Whereas if the house is fully occupied heat turned to normal and with doors opening and closing more heat will be lost to outside; all a function of the temperature difference between outside and inside, depending on your insulation and air exchanger, vents etc.
Where it gets confusing for some is that with the thermostat set lower the whole interior of the house, walls, flooring, furniture, appliances, books etc. etc. cool down to that lower interior house temperature and it takes time and extra heat to bring them back up whatever the occupants wants, after they get home.
But the' extra' heat is required only for so long as it takes for the house temperature to 'catch up'. It depends on the thermal mass of the house interior and it's contents. If one has a house constructed of masonry or brick and/or with concrete floors/slab it will take longer to bring temperature back up. A well insulated wood frame maybe less?
Conversely the next time the occupant leaves and turns the temperature down less (or no) heating will be required as the house structure/ contents cool down. It will be nice and comfortable; with 'no one' there, for quite a while.
Later the occupants return and will find the house chilly and that it will take several hours for the house and it contents to warm up again!
By the way. Lot of people confuse 'heat' (or absence of heat) with 'temperature', right?
Trying to explain to my neighbour that if we had three identical blocks of material outside in the cold, (or even on a regular cool day) one of concrete, one of metal and one of wood. They would all be at the same temperature.
But if/when he picked them up the metal would 'feel' colder than the wood. BECAUSE it would conduct HEAT away from his hand more quickly than the others. Even though all are at the same TEMPERATURE.
Have fun.
"Stormin Mormon" wrote
Hehe forgive while I feed the troll moment
Depends on how long you will be away and type of heating device used. 'Furnace' can be wood, coal, gas etc. I gather from the few with water boiler systems underfloor and such that it's not a good idea.
My heat is mostly gas. It costs the same no matter what hour it's used at, so reducing the temp for 8 hours at night when under blankets, can save a bit. Not much (might have been 2-3%) and we don't do it now because of the pets, but we used to when pet free.
The heat lost is the same as the heat you paid for. Lower temp loses less heat (or loses more slowly). So turning down reduces heat used, and fuel bill.
I think the lower temp is a savings, however long.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.