Conserving Propane

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Wow...what a winter! I've had to plow my driveway every day so far this week from either a big snow storm, a small snow storm, or wind driven snow. The wife crashed her Highlander yesterday into a telephone pole on slippery roads, and I got over 100 miles on my snowmobile...and its not even Christmas yet!!

After adding onto my house I had no idea what my heating costs would be this year, and so far I am not liking the math. Granted my house is double what it was, but it seems like I am using quite a bit of propane.

Currently I use have two propane heating systems. One is a Rennia heater in the old part of my house. It is a 30,000 btu unit that is direct vent and blows heat throughout my home. The new part of my house uses an 80,000 btu Munchkin boiler via radiant slab heat. The entire house is on concrete slab with 2 inches of strofoam insulation. The walls have R-19 and the ceilings, R-38, In short this should be a pretty tight house insulation wise.

For settings we have our new bedrooms set at 60º, and to be honest with you I don't think we can go much lower than that. The way radiant floor heat works, you really can't lower and raise the thermostats like you can with other systems; the delay is just too long (I think). But here is my question...

We set the Rennia on Low Heat at night. This allows the heater to put out a little heat, but not to any temp setting. In 8 hours or so, it will go from our preferred temp of 62º to 52º or so. That is kind of chilly, so when we get up in the morning, we turn it back up to 60º for a few hours, then if we head to work, or go somewhere on the weekends, we drop it back down to low again. (54º-52º). My question is, are we conserving propane or using more? When we do eventually turn the heat up, the heater kicks into overdrive and warms the house up. But does this use more propane to do that (more of a degree rise) then leaving it at say 60º all the time. In that capacity it would run more often, but in shorter bursts.

I'm not sure where the answer is, but I firmly believe that this house is pretty tight insulation wise. Still do you think another layer of insulation would really help? (The wife thinks so...I am undecided). Either way the propane costs are starting to worry me. Propane right now is pretty cheap still ($2.30 a gallon as compared to heating oil which is $3.40 a gallon), but we just went through 35% of a 500 gallon tank in a month. Granted its been down to -6F and -7F below for the last few days, but man I know there are a lot more of those nights ahead of us. Its only December and we typically don't shut down the furnaces off until May.

PS...Anyone know where I can buy some wool sweaters on the cheap :)
 
hey travis dont have the answer for ther propane use i would quess that its the constant temp is better than hittin the gas and then shutun it down..as for the wool dont u have llbean out near you ?? they got good stuff and reasonble.. or you could just go by a sheep or scavange the skins from your deer hunters sucess and tan your own:rofl:
 
While I'm no expert on you situation I have been told by people that claim to be experts that when using radient heat such as in your slab, that turning down the temp while away is not cost effective. With forced air heat you feel the warmth and the change is rapid so, turning down the heat is an effective way to reduce costs when you aren't home. Radient heat warms the objects in your home and in turn, the air. Cycling it down and up means that you are constantly warming and cooling these objects that will eventually warm the air and it's not very efficient. Maybe you could turn up your radient floor heat a bit and keep it constant and cycle the forced air for the extra heat as needed or add a supplemental heater in the bedroom.
 
Move south. Uh-Oh, no, no, no. :eek: Don't do that! We are trying to talk you out of doing that. ;)
Hope wife is OK, crashes are always bad news.
I don't have any suggestions. Wool socks, long underwear maybe?
 
Well Travis, the first thing I would do is to sharpen up my meat axe and go looking for the "expert" that talked you into a radiant floor heating system. There you are in an area where the ground freezes 3 feet deep. Putting 2" of Styrofoam under the concrete is like peeing in the ocean, you feel better but no one notices. But this is ancient history, what to do now....:dunno:

In your neck of the woods, I would be looking for a soapstone heater/furnace. As I recall, Maine has more than a couple trees so fuel would not be a problem. The good thing about the soapstone heater is that the stone will hold the heat for quite a time after the fire is out, and translates into warming the house. Another option is coal stoker. I don't know the cost of coal in your area, so this option may cost more than the savings of not using propane. You could also install a slip-in wood-burning stove in your fireplace. Put it in in the fall, take it out and store it in the summer, perhaps. I have a friend that heats his house with such a fireplace insert, but we seldom get below 14 F.

If you decide on some other additional or replacement heating system, DO NOT use a hot water boiler with the associated piping. For some unknown reason, people east of the Hudson river think that hot water heating is so neat. I guess they like to spend their money heating water and wasting that heat on the way to the radiator. But heck, what do we know out here in Indian territory.

Travis, the only thing you did wrong was to listen to the guy that recommended radiant heating.

Shapton make good stones for sharpening meat axes.:thumb:

That is my story, and I'm sticking by it.;)
 
So far no wood burning stoves for this guy. As of right now, the insurance company I am with bans woodstoves, at least in outbuildings. That means propane heat for my shop to. You can have a wood burning stove in the house, but in doing the math, so far the cost of the wood stove, added with the extra cost of insurance, its cheaper to just buy more propane. Seems kind of silly with a 300 acre woodlot just outside, but the math doesn't lie.

As for the radiant heat, its the best heating system I have seen thus far. We have it at work and whatnot and it works exceedingly well. I am not sure what the frost depth has to do with anything though. Here its four feet deep, not 3, but with just a sheet of Styrofoam insulation on the ground, the ground won't freeze under it. This is not the cheap 2 inch Styrofoam you can get, but the 25 buck a sheet Styrofoam. As it is, my slab runs about 86-90 degree water through it, and the ground is 47º so that is only a 40 degree rise. Not bad. Around here radiant floor heat is the way to go and I don't know of anyone who dislikes it. Just expensive to install, but considering your concrete slab is your homes foundation, a major portion of your heating system and your floor to, well that 9800 bucks I paid is pretty cheap.

As for one of those outside woodstoves...ain't no way I am getting one of those wood burners. My dad had one and went from burning 8 cords to burning 20 cords. Then it burned his house down. In the last month there has been three other homes in this county alone (Waldo County Maine) whose outdoor woodstoves have burned to the ground. I know of two more on the way to work that are more than likely to burn the house down.

One thing Patty and I discussed was getting a service guy to come out and just do a double check of all all the propane fittings. In the last month or two we have had our entire heating system changed over. From adding a new boiler to redoing our tank. They checked everything then, but maybe there is a leak somewhere that they missed. 175 gallons seems like a lot of btus to be going through. Granted it has been cold with temps a bit below zero for a steady week.
 
Radient is a great heat and very comfortable, BUT i is not effecient when it is in a concrete slab, Mother Earth is a mere 54 degrees and she wants heat as well so she gets most of it. It is better put the temp level at a constant and leave it there. as for the forced air device, use a programable thermostat to kick on in the early AM before you rise and down after you leave for the day and back up just before scheduled to arrive home again, back down in the evening as you deline for bed.

I have the opposite problem. My Elderly aunt (92) fiddles with the thermostat constantly, last year she distroyed her last one by changing from heat to cold and extreem in each direction. I installed a programable one that she cannot find the controls as they are on the inside and I haven't shown them to her. She can raise or lower the temp if she is cold or hot but at a preset time, it will revert to the setting I provided. Right now it is set at 80 degrees but she is happy :p... I pay the bills, she is content... I'm broke:(
 
just curious

:huh:how does a seperate outside wood burner cause a house to burn down:dunno: my brother has one and there are several around me and knock on wood there havnt been afires becasue of them..the wood consupmtion does go up drastically and that was why i didnt get one... for my remodel and addition shop space...
 
I don't think your usage sounds bad considering how cold it is up there. In the coldest period since we've lived in this house we used about 250 gal in just over 3 weeks. Our house is 15 years old and is relatively energy efficient (could use more attic insulation) and we have a 95% efficient furnace and hot water heater. Our house is a 1950 sq. ft. ranch with a full basement. For the house and shop we use right about 1100 gal per year, each year for the past 4 years.

I don't understand the comment on the outdoor woodstoves burning a house down. The one my aunt and uncle have is a boiler unit that sits about 50' from their house. About the only way I could see it causing a fire is if sparks blew on the house--but spacing it away from the house and putting a spark arrestor on it should should mitigate that. The only connection between it and the house is a super-insulated set of tubing carrying a glycol mix and an electric circuit for the controls that open an close a damper to control the burn rate. That runs through a heat exchanger above an air handler to heat air that blows through duct work. It could also be plumbed through the radiant tubing. Theirs also heats their hot water, and as I understand it, they basically only need to feed it wood twice a day. Granted they are in Missouri, but the winters still get pretty cold there, just not as long.
 
travis, before you drop bucks for more insulation, find a local energy contractor who does energy audits, one who uses both a blower door and infrared photography....most homes are not as "tight" as we think they are...
if you do opt for tightening up your house? be sure to assure yourself of the requsite number of air exchanges per hour, this can be done using your forced air unit and a small bit of additional ducting....
read here;
http://www.energyconservatory.com/
 
:huh:how does a seperate outside wood burner cause a house to burn down:dunno:...

Pretty easy actually. The fire occured at my dad's house because his stove (Taylor) did not have an ash pan. When you opened the boiler to add wood, ashes would sometimes drop out. We believe that is what caused the house fire initially. The insurance investigator claims it was poor wiring on the blower fan. Either way the fire started and got into the firewood he had stored outside the boiler. That 1/2 cord caught on fire and started to really burn. Radiant heat caused the vinal siding to melt and burn and it soon started his house on fire. Traveling up the walls it hit his attic and shot across. At the same time, the garage ceiling in his splout level home caught fire. At 3 AM they literally had fire under and over them and they were lucky to escape with their lives.

The fire in Frankfort started in a similiar fashion. Their firewood pile catching on fire and burning down their house through radiant heat transfer. The guy in Dixmont was a bit more foolish in that his was installed inside an attached shed. The scary part is there is a guy in Searsmont that does the same thing. I can honestly say his house WILL burn down at some point. I lieterally expect to hear it on the news any day. The installation is just that scary.

Here in maine they are pretty much banning them via insurance regulations and state regulations. I know Allstate Insurance will not insure a home here in Maine if you have an outside woodstove. Period! I know of a friend who installed one and his insurance was dropped instantly.

The State of Maine is also banning them due to their smoke. I do not know the exact regulations, but its something like if smoke from your outside woodstove blows across more than 2 abutting homeowners for more than 3 consective days you must shut the boiler down. There are some other undecided regulations too on them. I'll be perfectly honest with you, I don't like them. They burn a lot of wood. My dad was literally a slave to his stove. he was either getting wood for it, putting wood in it, or trying to find wood to put in it down the road. He went from burning 8 cord a year to burning between 18-20 cord.

No thanks, I'll cut 10 cord of firewood and sell it to someone that does burn wood. Right now seasoned firewood is getting around 245 bucks a cord. You can buy an awful lot of propane at that price.
 
thanks travis

it does make some sense now cuz the wood piles are usually close by the stoves.. hadnt thought about the amunt of heat from the whole wood pile burning that does increase the loss factor..and at 245 a chord you could make a pretty good wage..a young buck with a good supply of wood could do right well..
 
Radient is a great heat and very comfortable, BUT i is not effecient when it is in a concrete slab, Mother Earth is a mere 54 degrees and she wants heat as well so she gets most of it. :(

I guess I am not following you guys. Soapstone heaters are mentioned and yet they owe their effeciency to absorbing heat and being a huge heat sink. Heat is unique in that it cannot really be stored. Something like concrete or soapstone are either absorbing heat or giving it off. Certain products like concrete, soapstone and even wood transfer that heat at different rates, so in essence when the room is hot, they are absorbing heat, and yet at night when its cool they are giving it back. There is never a point in time where its being stored. Its either taking or giving.

My concrete floor does just that. It is a 22 cubic year heat sink. I heat it via warm water and it gives off heat. Since it has 2 inches of strofoam under the pad, and all around it, it is thermally isolated from the ground. The heated pad is never in contact with the ground surface therefore the 47 degree ground (here its that cold, that is why heat pumps just dont work) is never a factor. It also works quite well because heat rises. Since the top of my slab is the only place that is not blanketed with sytrofoam insulation, its the only spot it can release its heat. I know for a fact its not losingthat much heat off to the sides because we have 2 feet of snow on the ground and the snow is not even melted there. Its pushed right up tight against the house.

Maybe the snow is the real propane saver here. Now that we have 2 feet of snow on the ground, my house and my shop are nice and snug and not using the propane like I was. With another foot and a half coming sunday, I guess I should consider it more insulation. :) The only problem with that is that its piling up on the leeward side of the house. Just might have to get up there and shovel it off.

What a winter. Every day for the last two weeks the snow plows have gone by the house. The forecasters call for a dusting and we get 3 inches. yesterday they said 1-3 and we woke up with 5 inches of new snow on the ground. Here it does not melt like it does elsewhere. 20 degrees during the day and 3-7 below at night. Its going to be a LONGGGGGGGG winter!!
 
My question is, are we conserving propane or using more? When we do eventually turn the heat up, the heater kicks into overdrive and warms the house up. But does this use more propane to do that (more of a degree rise) then leaving it at say 60º all the time. In that capacity it would run more often, but in shorter bursts.

I think I'll try to address your actual question, since no one else seems to be. What you need to know is if your heaters are designed to have a lower heat output in BTU/hour when demand is lower. If that is the case, then the rate of heat loss/replacement becomes important to efficiency. If the heaters are just on/off affairs with thermostats attached to tell them when to turn off, then it is more efficient to add heat when you want it than to maintain a constant temperature.
 
Yes both the forced hot air heater, and the boiler modulate, that is adjust the amount of BTU's coming out of the unit according to what the actual demand is.

The boiler has thermostats but they are pretty dumb, it just tells the control valves to open or close. The programmable plc actually controls the temp of the boiler, the hot water tank and the temp outside, and the mix temp of the radiant fllor water circulating through the slab. If the thermostats give the plc a call for heat, it opens up the control valves, adjusts the water temp, etc.

On the rennia forced air heater, its altogether different. The heater is self contained with no thermostats or anything in the room. What it does is sense how COLD the RETURNING air is coming back to the heater. It does not come on because a thermostat in the room somewhere tells it its not hot enough. It adjusts its btu output according to how cold the air is coming back to it.

Years ago we had a 52,000 btu propane heater. When it got down to 20-30 below zero, the pipes in the bathroom would freeze. This new rennia heater is located further away from the bathroom then the old Empire heater was, yet the pipes have never frozen and it has got down to 32 below on occassions. It hasn't because as the heated air is sent out, the cold air is forced back through air convection. Its an odd way to design a heater, but it works well. You just cannot have a drafty house. If you open a window a crack, the heater senses the cold air coming to it, and goes to full throttle. Luckily I have a tight home. (When it gets to -55 degrees F you tend to keep drafts in check :) )
 
Well, that does make it a bit more complicated.... I'd imagine you'd need to figure out how quickly the house looses heat, and the BTU/hour on the lower end of the heaters and compare that to the more complicated program of heating/cooling. Depending on how well insulated your house is, it may in fact be more efficient to maintain a constant level, rather like driving on the highway vs driving in the city. But you knew that, ;) that's why you asked!
 
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