Propane heaters : LUSENET : TimeBomb 2000 (Y2000) : One Thread

Does anyone know of any websites that has information about heating with a propane heater (coleman type?). My neighbor asked me to look up the info for her, but I'm not having any luck. She needs information regarding the amount of propane these heaters require in relation to the time being used, safety, etc. If anyone has any information I would greatly appreciate it.

-- Val (, November 08, 1999


Don't know about 'coleman' types, but a friend had a medium sized ventless propane heater and using it as a primary heat source went through a 20 lb bottle in about 6 days. I looked at propane heat alternatives, but decided to go K1 for backup (Wood heat is already our primary)

-- BH (, November 08, 1999.

Val, I just bought one of the coleman flameless heaters yesterday it runs on the small canisters and it is safe for indoor use. It puts out aprox. 3000 BTUs and cost $45 at sports authority. I ran it last night on high and it ran for 8.75 hours

-- BrianNJ (, November 08, 1999.

Check the Prep forum...lotsa good links/threads

-- Billy Boy (, November 08, 1999.


The large 20 lb. tank (BBQ gas grill tank) contains a little more than 400,000 BTU (energy units) of propane. The heater's rating should be specified on the box or the instructions. The heater's rating will be specified in BTU (British Thermal Units?). If your heater is rated at 10,000 BTU, then this means that it uses 10,000 BTU per hour. You can estimate the length of time the tank will last by dividing the 400,000 BTU it contains by the heater's rating. Thus, a 10K heater would run forty hours (that is, 400,000 divided by 10,000 equals 40 hours). If the heater is rated at 20K BTU, then it would run about 20 hours.

Propane heaters are pretty safe. They will not emit cabon monoxide so long as they get enough fresh air. This means you will need to ensure ventilation of the room the heater is in by leaving a window partially open. I know that leaving a window open kind of defeats the purpose of running the heater, but the heat from the heater should more than offset the cold from the window. The newer and more expensive heater conatin a built-in oxygen sensor and shut off the hater of the O2 supply falls below the proper level.

Hope this helps,

-- Uhhmm... (, November 08, 1999.

I just looked up some propane numbers on a couple of web sites ... It looks like....

1 lb = approx 21,000 btu, so a 20 lb tank 80% full (typical) would be 16 x 21,000 = 336,000 btu

So for my particular Coleman heater at its minimum setting of 12,000 btu/hour a 20 lb tank should last 336,000/12,000 = 28 hours.

This assumes approximately 100% efficiency for an unvented tank- mounted radiant heater ... Vented heaters would be less efficient, perhaps as little as 75% efficient.

Can anyone out there confirm these numbers?

-- John (, November 08, 1999.


Send her to K-mart(walmart, sears ect) and have her look at the box that the propane stoves comes in. It will give you the hours of usage for propane bottles and cylinders.

-- Ned P Zimmer (, November 08, 1999.

Thank you EVERYONE for replying - I have the information I need for my neighbor, now! Again, thank you!!

-- Val (, November 08, 1999.

Oh, and my neighbor says a big thank you, too!! I wasn't sure about the propane heaters, as I've never seen one.

-- Val (, November 08, 1999. Here's an informative link on vent-free gas heaters.

-- Norm Harrold (, November 08, 1999.


Why should the tank typically be 80% full? Is there a technical reason for this, or is this just an average figure based upon every tank being used for something else up until the CDC? I am interested in this, because my calculation for my own usage is based upon the BTU contained in several full tanks. Thanks in advance for your your help.

-- Uhmm.. (, November 08, 1999.

When I was back in Colorado, I bought one of these for my daughter at Home Depot. Far less expensive than a kerosine heater...and less smelly. Also very good for camping!

-- Mad Monk (, November 08, 1999.

I had 2 tanks filled last winter - the guy overfilled them - they were fine until this summer when the temp got over about 85, then they started spewing out of their safety valves (wasn't to safe) - 80% sounds good to me if the outside temp is cold

-- BH (, November 08, 1999.

Uhmm, from the 'General Cylinder Information' section at the following link.... LP-gas, usually propane, is sold and stored in containers that, when properly filled, contain about 80 percent liquid, as shown in Figure A to the left. The remaining 20 percent of space above the liquid contains propane vapor. (It is this vapor that burns in your appliance when mixed with air.) The vapor space in the propane cylinder also provides room for the liquid propane to expand if the cylinder is exposed to warmer temperatures.


-- John (, November 08, 1999.

Propane expands as it warms. The 80% fill allows for expansion within the tank. Overfilling is not a good idea, especially if the tank is indoors. Tanks are usually painted white, beige or silver to reflect heat from sunlight and lessen expansion. Painting a propane tank with dark colors is also not a good idea.

-- Sam Mcgee (, November 08, 1999.


I called the local propane company and the representative that I spoke to said a 20 lb tank is filled with 18 lb of propane, which is 90%. However, that's not where we get our tanks filled, so I guess we pick a number between 80 and 90% of capacity and run with that to work out the number of btu's available.

-- John (, November 09, 1999.

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