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My cabin. 16×17 added onto the camper. About to run the wall around the camper, and put a roof over it. All tied together, and opened up inside, it’s still not all that big.
I have a fantastic woodstove, but am looking at the times when the stove burns out and the place gets cold. (Nighttime, times when I am away, if I get too sick to deal with the woodpile, etc.) I have a gas forced air furnace. 80k btu. I know that you are supposed to replace the orifice to run it on propane. Propane orifice being bigger than natural gas. Since I probably don’t need all 80k btu for such a small space, I am wondering if I can just run the thing the way it is.
Will it actualy use more propane with the smaller orifice, will I save money, or will it be a draw ?
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When i bought my propane water heater, i wanted one i could convert eventually to NG. I was told so many people had blown things up not getting it right that water heaters are no longer made (except for trailers, presumably because the fewer of them the better) with interchangeable orifices. The theory seems to be that any fool DIY'r will tackle a water heater, but leave a space heater to a competent tradesperson who might know what she's doing.
Contact the manufacturer or a heating supplier and get the right orifice, so that it comes with the right threads, etc. No need to filter Mt. St. Luka out of the drinking water for the next coupla weeks...
*I have a friend with an old cookin' stove that needs to be converted, but it works just well enough that he never gets around to it. However, due to the poor mix of gas/air the things builds carbon like crazy. You could spend more time cleaning the cabin than you would replacing ten orifices (orifi?).
*Thats what I was gonna say- it might burn real dirty. My experience has been that even when converted by the propane guys they never seem to burn right.
*So, it will probably not burn clean. I will probably have to remove and clean the combustion chambers once a year or so. (All the soot will be inside there, by the way, not out in the air I am breathing, and all over my furniture.)This is good to know. But what I really want to know is whether it is really neccessary to replace the orifice when I am using a furnace designed for a much larger place to heat such a small space ? The gas orifice is smaller than the propane orifice. If I were to try to burn NG in a furnace with a propane orifice, there would be way too much gas getting through, and therefore a fire hazard would definately exist. I can see that. But I am going the opposite direction. It takes more propane to obtain the same BTU's as NG. Using the existing NG orifice and burning propane instead, will net less btu's and virtualy no fire risk. But what I need to know is... will it be so inefficient as to be a waste of time and a waste of propane ? Will it put out enough heat to make it worth the effort, or will it never heat the chamber enough to produce much heat ? Etc. I am not concerned with whether the furnace will produce tons of heat, just that it produce enough heat to keep the small place I have, warm. It doesn't have to produce the kind of heat it was manufactured for. It is not in a large house, nor will it be connected to a central ducting system. Just sitting in the corner, throwing heat out the top whenever it is required to...
*Hi Luka,About 6 years ago I converted my furnace from LP to natural gas. I remember I needed to replace the control valve and the orifices. Approximately 2-300 bucks. So are you sure just the orifices need replacing? If so, they must be really cheap (less than $10), can't you get them?regards, jim
*HmmmmmHadn't considered the possibilty of having to replace the control valve as well. I guess it's time to take the thing apart and get all the info off it that I can find. Then I'll do a web search. I was hoping there would be a quick answer to this. Oh well, gotta finish the roof over the camper today before it starts raining. I'll get to the furnace later. Probably tomorrow.Thanks all.
*Luka the quick answer is hook the sucker up and see what happens. Thats what I do. (a lttle too often).
*Luka,Do not just hook it up. Sorry Lonecat. The orifice is bigger in Nat. gas than propane. You may have a jet engine depending on pressure. If you want to try to convert the correct orifice is #39 drill size @ 11" wc sealevel. Also hook up a needle valve close at hand to regulate with. Start off with the regulator turn low. Gonna need to change and/or adjust the pilot burner orifice. Adjust the primary air down by half. Probably some more things to do that I don't know.How bout I just send you a gas log starter that you can slap in that wood stove?KK
*I was under the impression that propane orifices are larger than natural gas for the same btu. But you say it's smaller. Is it because the propane is higher pressure ? Is the propane at a higher pressure ?Looks like it's time to put it on the back burner while I do a buncha research.Thanks.b : )
*Careful, buddy...Propane has about 250% more BTUs per given volume than natural gas...that's why propane has a smaller orifice that natural gas.The biggest danger is in overtemping the appliance and creating a fire hazard...on the bright side, you wouldn't need an oven to cook yout T-day turkey.
*LOL Thanks. I won't do anything at all with it until I am sure. I wonder why the cooks are always griping about how propane stoves don't get as hot as natural gas stoves ???
*All propane units put out less btus then whene set up with natural gas.Go to the store and get the conversion package for your unit. If one is not available, then don't do it.near the stream,aj
*Jack, if my boiler is rated at 130K and i install a different insert, are you saying the capacity of the boiler changes? Then i'm wondering how they can rate them w/o referncing the type of fuel...?
*Luka,Been thinking about your conversion. Look at the regulator and see if the cap on top unscrews. Under that cap is a little rod with a ring in middle. Flip that over. That should set the pressure to propane specs. Your propane supplier should have the correct jets, or they may be in a bag taped inside the unit. Install a needle valve and start off slow.Set the primary air so the flame is blue and not jumping off the ports.I have converted a bunch of these. My outside cooker is a burner out of a floor furnace with no jets. I can get a 3 foot circle of flame 6 feet high!KK
*If you change gas without changing the orifice, then the BTU's change. You change orifices when you change types of gas, to keep the appliance at the same BTU rating.I don't know about your boiler, but my furnace has natural gas very clearly referenced on the main info plate.
*Thank you KK. I will be taking the furnace apart this weekend or the beginning of next week. As in checking the cap you reference, as well as taking the combustion chamber apart to look for the orifice. Also to see if there are two orifices, since it looks like there are two seperate combustion chambers there.I will check with the guy who fills my propane bottles, next time I go there, about the jets and a needle valve. I also intend to check the whole furnace for leaks, and to clean out the combustion chambers, etc.I can do this. I used to install/clean/convert furnaces for a living. It was so many years ago that I have forgotten a lot of the specifics, but I remember enough that it will be like getting back on a bike.
*So, Luka, you figure vented or non-vented is the way to go with this? =)))))
*LOLMy present propane heat, a burner on the cookstove, is non-vented. But I am going to vent the furnace anyway.b : )I don't even know if this furnace is worth all the trouble. Whoever had it before, threw it out for some reason. I have just been hoping that they did so because they wanted/needed a bigger unit, or some such thing. I have to get it apart to find that out. With the combustion chambers removed and freely inspectable I can make a determination whether it is worth dinking with the rest of the thing or not.
*Hmmm, costing out Class B pipe and parts.....what about one of those little ceramic heater dealies or oil-filled radiators instead? Yeh, i know, where's the thrill in that...
*If this costs me as much as it would cost to just outright buy some alternative, it simply won't get done. The alternative won't get bought either.Trying to make do here...
*LukaK Kearney (post # 8 and post # 12) is right)also you need to change the pilot orrifices in addition to the main burner orrifices. Post # 12 is wrong. A nat. gas furnace can be converted to LPG and still put out the same BTUH as with Nat gas. Propane does operate at a higher pressure 11" water col. for propane and about 3.5 in. water col for Nat gas.LPG (propane) is dangerous stuff to play around with if you are not careful you may have to replace some hair and eyebrows, or maybe even your cabin. Suggestion: if your wood stove is properly vented you can make yourself a pipe burner that you can hook up to your LPG tank which can be used to start fires or can be used by itself to heat the stove in emergencys but not while you are away. I do this by adding a 1/2 inch gas valve with a air hose type Quick connect(male) onto a three or four foot long piece of 1/2 in gas pipe then put a cap on the other end and bore about two 1/8 inch holes behind the cap. insert this into the heater and hook to the hose on your tank for heat. This will use some gas but it will heat up fast and is great for starting fires.(Be sure to have some kind of fire in the stove before you turn on the gas)As for your furnace you might check to see if it might have already been converted to Propane a lot of people do this without marking the furnace.
*I may try the gas pipe idea. The woodstove had a crack across the top that was welded when I got it. The crack has opened up again, and the woodstove has never gotten very hot at all. Point is, I may end up having to break down and buy a woodstove, so it may be that I will be willing to put some sort of pipe into this one.
*Luka, My solution is both cheap and easy. I heated with a wood stove in the North Georgia mountains for a couple of years. Even with an air-tight stove, the double arm load of seasoned oak would burn up before morning. Simply drink a big glass of water before you go to bed. When you're up around 2 AM, throw some wood in the fire !!!
*ROFLMFAOI usualy do get up at least once during the night. Lately it's getting to be two and sometimes three times. I'll have no problem following those directions. My problem lies in 1). Having enough semi-dry firewood, and 2). What happens when I am too sick to do anything but drag my butt to the crapper and back to bed. (Already happened twice since I've moved here.) The burner on the propane cook stove has always been enough to heat the tiny camper up above the freezing point, at least. But in the larger cabin, I'll need something larger for those emergency times, hence the furnace.
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My cabin. 16x17 added onto the camper. About to run the wall around the camper, and put a roof over it. All tied together, and opened up inside, it's still not all that big.
I have a fantastic woodstove, but am looking at the times when the stove burns out and the place gets cold. (Nighttime, times when I am away, if I get too sick to deal with the woodpile, etc.) I have a gas forced air furnace. 80k btu. I know that you are supposed to replace the orifice to run it on propane. Propane orifice being bigger than natural gas. Since I probably don't need all 80k btu for such a small space, I am wondering if I can just run the thing the way it is.
Will it actualy use more propane with the smaller orifice, will I save money, or will it be a draw ?