Another Shop Heating Question

[tmc_31]

Hi all,

I was just reading Tony's thread about kerosene heating in a wood shop. I did not want to hijack his thread so, although a related topic, I will pose this question here.

Last year I bought a propane fired "top hat" heater. This heater is about 18" in dia. at the base and about 24" tall. The heater sits on the floor. It is rated at 90,000 btu. I have it hooked to a 30# drum of propane. My problem is when I run the heater for more than 20 minutes or so the propane tank cools off so that the btu output of the heater goes to nearly nothing. Short of setting the propane drum on top of the heater , I am not sure of how else to resolve this situation. Any (safe) ideas?

Thanks,

Tim

[MrSleepy]

That does happen when you draw the gas off too fast..The propane needs energy to go from a liquid to a gas...and it cools the cylinder in the process..

When we used to heat a large building from propane heater we usd to parallel four large bottle on "tee pieces" to share the load...that way they didnt freeze up..

Rob

[barts]

My problem is when I run the heater for more than 20 minutes or so the propane tank cools off so that the btu output of the heater goes to nearly nothing. ... Any (safe) ideas?

Place the propane cylinder in a large trashcan full of water.... this will let you pull gas off for a lot longer since the heat transfer to the tank is greatly increased.... and a small thermostatically controlled immersible heating element can be used (w/ the tank OUTSIDE, of course) to help matters further.

For really serious propane users, there are propane boilers that boil liquid propane... these are used for large scale flame effects at shows, etc.

- Bart

[tmc_31]

Thanks for the thoughts guys,

MrSleepy,

I had thought about getting a larger tank so as to "share the load" but your idea may have more merit by providing more tank surface area. Unfortunately I am somewhat space limited and using more than one tank will make that problem worse.

barts,

The trashcan full of water may work.

Tim

[dhammer]

90,000 btu is too much for a 30# tank..it will, as you've experienced, freeze down. You need a bigger tank or as others have mentioned more than one tank manifolded together. You mentioned a lack of room..for safety's sake the tank should be outside your shop..not next to your heater. I think the warning label on your tank specifically states that a propane tank should not be brought into a heated building.

I work for a propane company and fill cylinders all day long. Every once in awhile some one brings in a cylinder that was overfilled by some inexperienced convienence store clerk. An overfilled tank brought into a heated building next to a heater is a disaster waiting to happen.

Steve

[Bones]

sometimes hanging a lightbulb next to the tank outlet helps. used to have to do that in Fairbanks to keep the regulator from freezing up.

bones

[38_Cal]

Another few years when all the incandescent light bulbs are outlawed and all we have are CF and LED lights, and you won't be able to do that. But we'll be green!

David

[Boucher]

I was able to run one of those with a 100# bottle fairly well. The 250 gal tank was even better. If I was having problems with the 100# tank I would just set it a little closer to the heater. This was in a 40X 80 shop with 16 ft. sidewalls. Probably was not legal to have the tank in the building but we were outside the city limits.