folks running propane, need some real world numbers here.

I've been on a propane stove for a long time, it's use of propane is negligible, maybe 50 gallons a year with alot of heavy baking. I'm heating the house primarily with forced air outdoor wood furnace that I built myself, works like a champ. My current hot water heater is a 40 gallon electric. I'm wanting to remove the electric furnace from the house as it is a real energy pig AND won't heat during a power outage. I have already purchased the propane heater that I want, a 30,000 btu blue flame ventless to use as emergency heat (like when I'm sick or injured and don't want to go chop wood). I will keep the electric hot water heater hooked up, but that is our biggest expense in energy now, so I have already acquired a propane on demand hot water heater, my thoughts are to use the electric one as a pre-warmer set super low so it won't use much power, then run through our on demand unit before going to the house. That way, I've still got electric if I need it, but the propane will be taking up most of the heavy use.

I can't find a local propane company that is worth a hoot, so I'm just going with 100lb cylinders filled at tractor supply, amazingly it's cheaper there than buying in bulk from any of the local jerks. I'm not really doing this for cost saving measures, as I don't think I'll see much of a cost reduction, mainly for being able to run the house off of a small generator if need be and having endless hot water I like my big bathtub alot...

I'm just curious if anyone else is running a stove, hot water heater, AND small 30k BTU heater off of 100LB cylinders. What is your climate like and how long do you expect 1 tank to last? I understand the math behind it, btu's and usage divided by hours and blah blah blah, but I prefer getting some real world stories as I find the math rarely translates into real world usage very well... I also understand there are lots of variables, I'm not interested in determining all those, just if you run a house off of 100lb propane bottles and how often do you switch them or at least someone who runs a similar setup and can tell me how many gallons they go through in a typical winter or year... oh, and YES I do know I'll have to run several at the same time to get the surface area of propane I need to be able to boil off.

Thanks in advance,

Ajila Ama Farm

Welcome to permies.com.

I have never heated, long term, with propane, so I can't help you there.
But, I do love those 'on demand' gas water heaters. I think that the real secret to their success is to install them where the water line from the heater to your sink/tub will be as short as possible. I don't really see an advantage to preheating the water before it gets to the heater, although this would give you a backup if you ever run out of propane. Electric is not a cheap way to heat things - it consumes a lot of energy trying to overcome the resistance that generates the heat - a minor 'short circuit' is how I describe it.

OK, since you just want the heat for emergencies, I would plumb the furnace up with its own 100 lb tank and leave it full. If you have to use it, then rotate that tank to the cookstove so you can put a FULL tank back on the furnace ASAP.

While you are at it, I would probably hook up the on-demand water heater on its own bottle, too, because they usually use about all the regulator and hose can put out when they are going. I looked at getting one but would have needed a second tank because I couldn't push enough BTU's through the existing regulator for the water heater, stove, and furnace at the same time. Some even need a higher pressure regulator than "normal" appliances.

Buenos dias. El propano no se utiliza en los Estados..... excuse me

Propane is not used as much as a whole house energy solution in the United States as it is in Mexico. Oh sure, if you drive through rural areas in the U.S. you can see 100 gal propane tanks next to the house, but this is more of an indication that they don't have piped natural gas in the area than anything else. But in Mexico, even in large cities, houses are on propane. When I lived in Ensenada, the propane truck would drive slowly through the neighborhood a couple days a week and toot his horn. If you needed a fill-up, you waved him down and he would fill your tank with a long hose from his truck. In my house, the stove, water heater, and dryer were on propane, and I didn't have any space heating. In the winter months (when I ran the stove more), I could go two months on a 100 liter fill-up.

It's space heating though, that runs through the propane. Neighbors who had space heaters would go through a 100 liters in a week (hence the frequency of the delivery truck). Fortunately, the heating season in Baja tends to be measured in weeks, not months, so that high demand for propane was only for real Arctic blasts coming down from the U.S.

thank you folks, good information about the on demand unit... My propane is a little more than "emergency" heat, but it is not our main heat source. During a normal winter I use the wood a solid 85% -95% of the time. During fall and spring, it isn't really worth it to start a fire that will only be used for a few hours during the night so I use the electric during these "in between" times where it only gets cold for a few hours. I just got the blue flame heater hooked up and running it off of a grill tank just as an experiment, it has a nice thermostat on it so I'm curious to see how long the 4 gallons in the grill tank lasts, that will give me a little bit of an idea... When I heated my shop with a 30k BTU radiant propane heater (the kind with the bricks w/ tiny holes) it had to run full blast to overcome the concrete slab and poorly insulated garage doors. Running full blast, it cost me about $1.50 per hour (I can't remember the cost of propane during this time).

I have no idea what will happen with the thermostat to actually regulate usage, but at least I'll have some sort of baseline to judge from. We're expecting a cold week here in western north carolina (chilly at night anyhow) so maybe that'll give me some clue...

Regarding the advice on having each unit on it's own circuit... I may go with that. The one 100lb tank for the kitchen stove lasts approximately six months and we do a fair amount of baking. I imagine due to surface area alone (for the propane to turn to a usable gas) I'll need at least two plumbed together for the heater AND for the water heater.

The reason for pre-heating the water going in to the gas water heater (from what I understand at this point but I am new to these) is that I don't have to run the water heater full blast to heat the water to a usable temperature, I can turn the main valve down a bit. Luckily (in a sense) we have not started building the house yet, so we are in a 14x56 mobile home, the longest run the water heater would have to make is 20 ft. away... This is a BIG unit, 90 degree temperature rise at 4.5 gallons per minute, got it for 10 bucks at a thrift store haha, ridiculously good deal...

M Foti wrote:thank you folks, good information about the on demand unit... My propane is a little more than "emergency" heat, but it is not our main heat source. During a normal winter I use the wood a solid 85% -95% of the time. During fall and spring, it isn't really worth it to start a fire that will only be used for a few hours during the night so I use the electric during these "in between" times where it only gets cold for a few hours. I just got the blue flame heater hooked up and running it off of a grill tank just as an experiment, it has a nice thermostat on it so I'm curious to see how long the 4 gallons in the grill tank lasts, that will give me a little bit of an idea... When I heated my shop with a 30k BTU radiant propane heater (the kind with the bricks w/ tiny holes) it had to run full blast to overcome the concrete slab and poorly insulated garage doors. Running full blast, it cost me about $1.50 per hour (I can't remember the cost of propane during this time).

I have no idea what will happen with the thermostat to actually regulate usage, but at least I'll have some sort of baseline to judge from. We're expecting a cold week here in western north carolina (chilly at night anyhow) so maybe that'll give me some clue...

Regarding the advice on having each unit on it's own circuit... I may go with that. The one 100lb tank for the kitchen stove lasts approximately six months and we do a fair amount of baking. I imagine due to surface area alone (for the propane to turn to a usable gas) I'll need at least two plumbed together for the heater AND for the water heater.

The reason for pre-heating the water going in to the gas water heater (from what I understand at this point but I am new to these) is that I don't have to run the water heater full blast to heat the water to a usable temperature, I can turn the main valve down a bit. Luckily (in a sense) we have not started building the house yet, so we are in a 14x56 mobile home, the longest run the water heater would have to make is 20 ft. away... This is a BIG unit, 90 degree temperature rise at 4.5 gallons per minute, got it for 10 bucks at a thrift store haha, ridiculously good deal...

to fotie... I just bought the sames 30,000 btu blue flame heater you have and was going to hook mine up the same way you did off of the grill tank. my question is.. did it work and how long did it take for the tank to go empty? thanks