Room Temp Setback Poll

I'm all in favor of relying on cheap coal BTU's to keep the house at a comfortable temperature. The point of a setback is to reduce the amount of work the heating system has to do at times when the heat isn't contributing meaningfully to comfort. As a matter of thermodynamics, I don't think it's arguable that setbacks reduce BTU loss and fuel requirements along the lines that lsayre computed. Anybody who has ruled out use of setbacks on the basis of a belief that it doesn't reduce BTU loss and fuel requirements probably should reconsider.

For those who have ruled it out on the basis of control issues, I would suggest that you look further at what is going on with those. If you can't decide to push the heat down by a few degrees and then hours later push it up by a few degrees without creating problems, it seems like your system is kind of unstable. Even a hand-fired appliance can be banked to run easier overnight.

In the end, people obviously can decide to do whatever they like. I elect to reduce the nighttime temp by a few degrees, and at my coal usage rate the savings are measured in tons and in hundreds of $ per heating season. The absolute savings in more conventional settings no doubt are smaller, but on a percentage basis I think that 3% savings per degree of setback is a pretty good number.

Mike

For those who have the super insulated buildings, a set back might add up to some savings with little to no comfort loss. For those of us who have the less than perfect buildings (2x3 walls.concrete blocks,uninsulated concrete slabs) there is too much of a dis-comfort level to be worth setting the t-stat back.Our shop is a perfect example,set it back at nite,set it up in the a/m @ 6-7 a/m & it still FEELS cold yet at 10-11 a/m even with setting t-stat up 5* higher than normal. We have found it just is not worth the dis-comfort level.If we burn an extra 3% per yr then we have spent around $100-$120 more for the yr for comfort. Most of you folks spend more to watch TV than that per yr.We spend $34/mon less not having cable,my wife is a very good cook,we do not eat out,our vacations consist of us working in the garden rather than the shop. So we spend a minute amount more (maybe) on coal to be WARM.

It is different for everyone. I think that leaky buildings with high powered heating systems probably benefit the most from temperature setbacks. Multiple zones make a difference too. In my case the downstairs is one zone, and is the lion's share of the total load. The upstairs and bathrooms are separate zones. I can set the downstairs at 65 degrees at night, and never notice from the upstairs since that zone is controlled separately. When I get up in the morning I bump the heat back up, and by the time I get out of the shower (bathroom is always set at 75 ) the downstairs is back to 70 or 72, whatever I set the thermostat to.

windyhill4.2 wrote:For those who have the super insulated buildings, a set back might add up to some savings with little to no comfort loss. For those of us who have the less than perfect buildings (2x3 walls.concrete blocks,uninsulated concrete slabs) there is too much of a dis-comfort level to be worth setting the t-stat back.Our shop is a perfect example,set it back at nite,set it up in the a/m @ 6-7 a/m & it still FEELS cold yet at 10-11 a/m even with setting t-stat up 5* higher than normal. We have found it just is not worth the dis-comfort level.If we burn an extra 3% per yr then we have spent around $100-$120 more for the yr for comfort. Most of you folks spend more to watch TV than that per yr.We spend $34/mon less not having cable,my wife is a very good cook,we do not eat out,our vacations consist of us working in the garden rather than the shop. So we spend a minute amount more (maybe) on coal to be WARM.

My building is not well insulated. It has loads of uninsulated masonry, and probably shares some of the thermal mass characteristics of your shop. We have dealt with the "time delay" issue by starting the setback before we actually are going to bed, and returning to the daytime temp early enough for the system to have time to respond. The same thermal mass that takes time to heat up in the am provides plenty of heat in the evening, so the system gets the same amount of "rest" (in our case, 9 pm-4:30 am). In your case, maybe the shop could go on setback an hour or two before you finish work for the day, and start reheating it a couple of hours before you need it? I'm not saying you should do that; I'm just sharing our experience in dealing with the time delay. If you're using 13-14 tons per year for heat (and the rest for DHW), setting back all of the heating loads on your system by 1-3 degrees should reduce your coal use by about 0.4-1.3 tons/year. It's your call whether the comfort effects outweigh the savings.

Mike

Apparently we setbackers are saving coal and money, but we're getting clobbered in the poll. To me it's weird to see it that lopsided, given the way coal use so often is motivated by the opportunity it provides to achieve heating cost savings.

Mike

Our business hours are from 8-8 M,T,T,& 8-6 W,F,& 8-4 Sat., so set back at 7 p/m,set-up at 4-5 a/m .. I will think about that possibility,i will also have to see what 120 volt programmable t-stat is available & how much x 2 for the shops 2 zones. Gives me something else to think about .

Heating with coal gives me the opportunity to keep my house as warm as I like without cringing and gnawing my fingers worrying about how much it is costing me.

blrman07 wrote:Heating with coal gives me the opportunity to keep my house as warm as I like without cringing and gnawing my fingers worrying about how much it is costing me.

Nobody is cringing or gnawing fingers. Are you still using the hand-fired equipment in your profile? Do you really push it harder in the middle of the night to maintain a single fixed temp, or do you bank it to last overnight and run it harder during the day?

Mike

Mike, Larry has mentioned several times that if his house cools slightly, momma is NOT happy. You do what you gotta do.

Yes I am saying, to some people savings from a set back thermostat is irrelevant. I do not burn coal as a hobby or to see how much money I can save heating my home.

Yes I bank it, I goose it with the ash door, I talk to it, I do whatever I have to do to maintain as close to a steady temperature with my hand fired VC 2310. I chose to heat our home with the 2310 because of it's versatility and it is an optimum size for our home. We heat the entire house with it. I cram as much coal in it as I can to ensure it stays burning at an optimum temperature all night even when we are sleeping. Yes I am using the VC 2310 which is the same stove in my avatar. I started burning on September 17 this year because it started getting cool here and I wanted to make sure my wife stayed warm. I also vary my coal between pea/range/nut and all nut depending on what I think the outside temp is going to be. I do whatever I have to do to keep a steady state at around 73-74. My wife of 42 years has anemia and asthma. Anemia causes extreme sensitivity to cold. She can sense a two degree change in the indoor air temperature. An Asthma attack makes it almost impossible for her to breath and has to be broken with medications. Temperature swings can trigger her asthma. When she goes out in the witner she wears up to five layers to stay warm and wears a face mask.

If you don't have any one in the house with health problems that are triggered by cold then put in that set back thermostat, dial it back, and save that 9% of your coal. It's cheaper for me to pay that extra $30-60 a month running at a steady state to keep her warm and comfortable and breathing steady.

Pacowy wrote:Apparently we setbackers are saving coal and money, but we're getting clobbered in the poll. To me it's weird to see it that lopsided, given the way coal use so often is motivated by the opportunity it provides to achieve heating cost savings.

For the same reason I thought it would be a more 50 - 50 split too, but maybe it is due to mostly older dial 'stats being used rather than newer programmable ones?

Pacowy wrote:In the end, people obviously can decide to do whatever they like. I elect to reduce the nighttime temp by a few degrees, and at my coal usage rate the savings are measured in tons and in hundreds of $ per heating season. The absolute savings in more conventional settings no doubt are smaller, but on a percentage basis I think that 3% savings per degree of setback is a pretty good number.

Was your 3% saving based on Isayre's numbers - if so don't you have to adjust that for the amount of time you are in set back mode? I thought his 3% number was for a full HDD so my understanding would be if you are setting back 8 hours a night (to make it easy) your daily savings would be 1/3 of that or 1% ? So my 1% savings on burning 5 ton per year would be 100lbs, am I off base there?

This is assuming creature comfort only. If your setback is for 8 hours the only way to know what your real savings are is to calculate how much you burn a day. 1/3 of that number times .03 will be your savings. Assume you burn 100 lbs a day. One third (8 hours) is 33.3 lbs. 3% of that is a savings of one pound of coal over the 8 hours of setback. Average bagged coal cost is around .12 per pound. Your mileage may vary.

If I did this right, your saving $.12 per day or $3.60 a month. It will take you almost 10 months to break even for the cost of the least expensive setback thermostat. Maybe a little quicker if you factor in the electric savings. After that it's savings.

OOPS forgot to factor in the coal you will burn to warm things back up when the setback time period is over. Something to consider. Most calculations don't include the amount you had to burn to get back up to temperature.

Did you really save anything or did you just shift the cost?

I'm not relying on lsayre's numbers. The 3% per degree figure he came out with is the same number I have seen from past field studies. No, you don't apply the savings only to a fraction of the day, and the fuel associated with getting the building back up to temp is already accounted for. Net BTU loss from the building is greatest at night, when the ambient temps are normally a lot lower than during the day, and solar gain is 0. Setbacks produce real savings by reducing the loss of BTU's during the time when the need for the system to replace BTU's is greatest. If you use 5 tons/year, a 3 degree setback at night probably would save around 900 lb./year. Around here that would be an absolute minimum of $90/yr, and for most people more like $125/yr or more. AFAIK basic programmable thermostats are $20-25 at Lowe's or HD.

On the health front, 3 in our house have asthma, and their conditions improved fairly dramatically upon our conversion to coal-only in 2004. Their remaining issues relate to things like teenagers declining to use their inhalers before attempting to play competitive sports, and have no discernible connection to our setback practices.

Again, I'm not saying everybody should be doing it, but the decision of whether or not to should be based on good info.

Mike

Well,the good info I have used & stand by to this day is how the house or shop FEELS,not just what a thermometer on the wall says. So far the best FEEL is an even temp 24/7. But I have no objections whatsoever if others use a set back in their dwelling or shop,i will not try to convince them otherwise because I don't care what they subject themselves to .

This thread has almost taken the fun out of coal burning & now even has me wondering about my fellow coal burners. Being retired & on a fixed income I have plenty of time on my hands but I do still have a life. All I can end up saying is that we all do what we do for our own reasons, mine was to keep a happy wife which in turn gives me a happy life. It is much easier to simply go with the flow than to spend a month or more creating flow charts & a power point presentation showing average mean temps, hours of daylight, windspeeds, historical weather patterns & probable future predictions based on climate change & the educations & backgrounds of all those involved with their horoscopes & family trees. If it all makes your boat float go right ahead but don't forget to add the cost of all the paper & ink or anything else involved. Now I have to go measure the interior volume of my Waste Management garbage can, I fear they have been overcharging me for the last 28 months. Now my wife won't laugh at me for weighing our garbage & taking pictures of our weekly offering.