Propane tanks and cold weather...

[tpjets62]

I presently have two 100 lb tanks that I use one at a time to run a 120,000 BTU heater. Presently we've had a few nights down to 2 degrees and I've had no problems. but with temperatures possibly getting down to 10 - 15 below zero, I'm looking at which would probably be the better way to go. The first thought is to get a heated blanket that covers the lower half of the tank, like one of the light duty power blankets, or would I be better off to hook the two tanks together through a manifold? The unit comes on a couple times an hour, and generally runs about 6 - 8 mins at a rip. Looking for opinions, thoughts.
Thanks!!

[TitanMike]

The issue with cold weather and temps like you stated is that the Propane will evaporate much slower. When I "wintered" in my TT the "gas man" told me that the best tanks for cold weather were horizontal tanks. More surface area for the liquid to evaporate and give you a good reserve of vapor to run the furnace.

With your 100# tanks which need to be vertical you could help things if you could manifold them together using a Y connector to the tanks and then attach the regulator to the Y. This way you've doubled the evaporation surface and as the tanks start to empty, more vapor in reserve.

As for a tank heater? Can only help more.

[5picker]

I've used tank heater blankets like you mentioned with good success.

Hooking the two tanks together 'may' get you enough liquid surface area where they will boil enough gas at the temperatures mentioned but maybe not.

That's why most larger tanks are horizontal. They provide way more liquid surface area that way.

If you have a way to use the heating blankets, that would be my choice.

[MR.M]

Originally Posted by tpjets62

I presently have two 100 lb tanks that I use one at a time to run a 120,000 BTU heater. Presently we've had a few nights down to 2 degrees and I've had no problems. but with temperatures possibly getting down to 10 - 15 below zero, I'm looking at which would probably be the better way to go. The first thought is to get a heated blanket that covers the lower half of the tank, like one of the light duty power blankets, or would I be better off to hook the two tanks together through a manifold? The unit comes on a couple times an hour, and generally runs about 6 - 8 mins at a rip. Looking for opinions, thoughts.
Thanks!!

All you should have to do is keep your regulator warm .

[TitanMike]

Originally Posted by 5picker

I've used tank heater blankets like you mentioned with good success.

Hooking the two tanks together 'may' get you enough liquid surface area where they will boil enough gas at the temperatures mentioned but maybe not.

That's why most larger tanks are horizontal. They provide way more liquid surface area that way.

If you have a way to use the heating blankets, that would be my choice.

True but at least the surface area will be twice as much as when just using a single tank

IF the temps don't go below -15 I wouldn't think that it would be too cold for the tanks to provide enough gas for the average RV furnace (unless the tanks are filled with a butane mix).

Propane doesn't stop boiling until -44 degrees and the general concensus is that real issues don't begin until -20 degrees and lower.

One way to decide is to contact the local gas Distributor. They will be in tune with the low temps that use of a 100# "bottle" will become an issue and if heat blankets are required.

BTW, my winter only got down to -15 and the furnace ran almost continuously.

[A32Deuce]

Your heater may be drawing more propane the the typical RV. Tied together will help as will heating. Heating helps with high vapor draw.

[Oldboy]

Hey, tpjets42.., thanks for this post, I'm heading out in February from southern Ontario.... I will need heat. The response from your post is good information.��

[5picker]

Originally Posted by A32Deuce

Your heater may be drawing more propane the the typical RV. Tied together will help as will heating. Heating helps with high vapor draw.

X2

A 120,000 BTU furnace is typical of a large whole home furnace and not a 35,000-40,000 BTU R/V furnace.

What works for a R/V may not work for this application.

While a 100# tank is taller and holds more propane, in its upright position, it doesn't have much more liquid surface area than a 30# tank.

Yes two together will help but I'd bet at 120,000 BTU, you'll need more help.

[tpjets62]

I'm hoping for next year to get a horizontal tank but for now just want to get thru this winter with out any major issues. I guess the bottom line is which solution at the present will work better at -15? One tank with a heated blanket on the lower half or 2 unheated tanks hooked together to draw off of?

[NMWildcat]

You don't say, but I'm assuming your RV is on a permanent site, or at least permanent for the winter?
Might call the local propane distributor and ask about costs of renting a larger horizontal tank. That's what we do on certain farms. Then when we don't need them anymore, they pick them up and refund us for any unused propane. Works out cheaper than owning our own tanks, and less hassle for us, all the way around.

[TitanMike]

Originally Posted by NMWildcat

You don't say, but I'm assuming your RV is on a permanent site, or at least permanent for the winter?
Might call the local propane distributor and ask about costs of renting a larger horizontal tank. That's what we do on certain farms. Then when we don't need them anymore, they pick them up and refund us for any unused propane. Works out cheaper than owning our own tanks, and less hassle for us, all the way around.

That's what I did when I wintered in Denver. The local Distributor dropped off a horizontal tank and put me on a "keep full" schedule. I'd come home from work every three to four weeks and find a bill stuck int he door handle of my TT. They also tacked on a really small rental charge which I can't remember exactly but it was really small and well worth it. Only real cost to getting the tank set up was the cost of a hose that ran from the tank to my regulator but their charge was very reasonable.

It sure beat having to haul 100# tanks around.

[aircommuter]

Sounds like you haven't had an issue yet. If you manifold the tanks together you will probably be covered for evaporation. Regulator capacity may be a problem. While a horizontal tank generally has more surface area it varies. Some high draw things like engines use liquid withdraw.
However my home generator is a 50KW powered by a 460 engine and it runs on vapor. I have 1000 underground tank so it never gets too cold and a 1-1/4" 10 psi line to the regulator and it is a 1 million regulator. try the manifold first.

[tpjets62]

I like the idea of a rental, I may look into that. As for my regulator, I'm using a Fisher unit, 2 stage adjustable that'll handle 550K btu.

[DouglasReid]

Originally Posted by NMWildcat

You don't say, but I'm assuming your RV is on a permanent site, or at least permanent for the winter?
Might call the local propane distributor and ask about costs of renting a larger horizontal tank. That's what we do on certain farms. Then when we don't need them anymore, they pick them up and refund us for any unused propane. Works out cheaper than owning our own tanks, and less hassle for us, all the way around.

Great bit of advice and knowledge. I don't need it now but it is stored in my on board computer..............Right between my ears.

GOD help me if ever that Hard Drive crashes!

[TitanMike]

Originally Posted by DouglasReid

Great bit of advice and knowledge. I don't need it now but it is stored in my on board computer..............Right between my ears.

GOD help me if ever that Hard Drive crashes!

Do you "defrag" it regularly

[rsdata]

I have a 100# tank that I use for home cooking stove, it got so cold one winter day some years ago that it would not get enough gas to the the stove and two burners to fix Sunday dinner... I went to the big box hardware store and bought a 25 foot heat tape...I started wrapping it around the regulator then up and down the side of the tank, taping it in place with duct tape... solved my problem...

that was some time ago and I have not had the problem again, so I no longer have the heat tape but it was similar if not the same as this I found on amazon...

[GHodge]

Propane is an ideal gas, the Vapor pressure is dependent upon the temperature. For example at -40 degrees the vapor pressure is 0 psi, it it can not exist in vapor form at this temperature. Therefore whether your have one tank or 3 tanks connected to a manifold the same amount of gas will be supplied to your heater. At -20 degree propane vapor is less than 20 PSIA or approximately 6PSI, with only 6 psi on the upstream of the regulator can the regulator deliver the volume required for your heater. Therefore the heat blanket is the only option for successful heater operation.

[djkarau]

I live in Canada where it regularly gets down to -40c. If the tanks are anywhere's close to full you will be fine. -15 is t-shirt weather up here!

[txarsoncop]

I use regular 20# tanks for pear burning (burning the thorns off of cactus so livestock can eat them).

On a 50 degree day after burning a while the tank gets so cold it's got ice on it and the pear burner barely puts out any heat. Turning the torch on the tank briefly melts the ice, warms the gas and gets the torch running again.

I'd say your heated blanket is your best bet with your heater application.

And no, I don't advocate heating your tanks with flame. Too much heat above the liquid can cause a BLEVE (boiling liquid expanding vapor explosion).

[TonyB]

Man, what an interesting thread. More to just about everything in life than I imagined. Thanks.