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sdrubrecht
01-01-2011, 08:07 PM
Just got back from camping at Quartzsite. Our thermometer said that it got down to 22 one night. Of course, I ment to change tanks and forgot (never again!). Woke up to no heater and 35 inside our 3010 cyclone. Went out and swapped to a full tank but only got an anemic flow. Furnace wouldnt light! Barely enough gas came out to get a flame on the stove. Started the genny and turned on eletric heater. Tried cycling selector switch a bunch of times, poured warm water over selector/regulator and tank but no luck (still had warm water in the water heater). About an hour after sunup, at a balmy 45, full flow started all by itself. Anybody got a clue what happened? Maybe some condensation in the regulator froze when I ran out of propane? Thought some of our northern neighbors might have an idea.

2psnapod2
01-01-2011, 08:54 PM
If memories serves me right, no propane does not freeze. It does however have an issue with not turning into a gas at really cold temps. I also know that in Wisconsin and other northern states it gets a lot colder than 22 degrees. So I doubt the actual propane was the cause of your no heat. I would think it was more likely that your regulator had some moister in it and that was what froze like you said.

lwmcguir
01-01-2011, 08:55 PM
Sure will at about -310F. Pressure drops off as the temperature lowers and that is why some folks in the North bury their tanks and supply lines. You probably opened the valve to quick and the high flow protection valve closed. Usually you can close the valve and then very slowly open it and correct/reset it. Your down stream pressure would have been very low after running out so you would have got a rush of propane when you cracked the valve open.

JohnDar
01-01-2011, 08:59 PM
Propane liquid gives off vapor down to -44 F, so your 22 F night isn't even close. It freezes somewhere around -300 F.

Buford445
01-01-2011, 09:04 PM
Seams like I have heard of the regulator freezing before from moisture

Willym
01-01-2011, 09:07 PM
Propane's boiling point is less than -40 F, its freezing point is substantially lower. It is successfully used for heating in northern climates.

Someone with LPG expertise may know better, but your theory of moisture freezing in the regulator/auto changeover sounds right. When the temp dropped you probably got some condensation and it froze when the tank emptied fully. When a tank is allowed to fully empty, gas expansion will cool the supply piping and equipment substantially and freeze.

JohnDar
01-01-2011, 10:07 PM
If it's working and he's using the auto-changeover correctly, he shouldn't have that problem. But it sounds like he was only opening one tank at a time and delayed doing the manual switch. If he physically changed the tank after it went completely empty, he may have introduced air into the system, as well. Sounds a little like that, too.

GOTTOYS
01-02-2011, 01:25 AM
As the outside temperature drops the pressure in the tanks will fall off but it will still be usable unless the level of fuel in the tank is very low. I have had the regulators freeze up a couple times at night when the temperatures dropped below zero....Don

lwmcguir
01-02-2011, 07:26 AM
I think the key here is as some posters noted, never letting the tanks run completely dry. The moisture in the tanks and in the air will cause problems with the regulator. We have used propane to heat houses, shops, and barns for many years and never had a regulator freeze. Never ran a tank dry either.

hoefler
01-02-2011, 10:47 AM
High flow restrictor is the culprit. Run out of propane, line pressure is 0, open full bottle to quick, flow restrictor engages, and you have very little flow.

caissiel
01-02-2011, 05:06 PM
We use propane in Canada as far down to -40F without any problem. But most tanks are 100Lbs or more. Its only lately that the OPD valves are available on the 30Lbs tanks but the 100 Lbs tanks are not equiped with the OPD valves. I was told that the 30Lbs tanks and valve system is at its limit if using a 40,000 BTU furnace.

It could happen that if the Furnace is going wide open and the 3 burners on the stove and the refridgerator would come on that the overflow valve would shut. Hope it don't happen to me but I figure that from the comments it could possibly happen.

I wonder what is being used on 100Lbs tanks as we don't have the same code in Canada and the OPD valve is not used on 100 Lbs tanks and it takes a different licence to fill these containers.

Jimmy
01-02-2011, 05:39 PM
Must open new valves very slow, especially when cold...

couch
01-02-2011, 08:15 PM
when you burn propane, you need to have the liquid in the tank to "boil/replace" the gas that you are using. if you are using a small tank with a large furnace, it is possible that you had little to no pressure in the tank to feed the furnace with. when you stop burning with your furnace, the pressure will build up in the tank then you can use it again. since it worked fine in the morning, that is what it sounds like happened to you.

superduty08
01-02-2011, 09:20 PM
I have many propane generators at work and when the temps drop much below freezing the tanks frost up while the unit is running. The generator will usually shut down sometime afterwards. We have found that using tank heaters solved the problem. They are bands about 8" wide that wrap around each 40# tank and provides heat. The heaters that I use are ac powered so they have to be connected before the tanks frost. I have been told that this lets the propane produce vapor when the temps drop. I have also been told that suppliers use additives by region so in the south I guess that we would not get the same protection added to the propane as a northern region. I have no expertice with propane but have found through years of experience how to beat the cold tanks. Hope this might help.

leftyf
02-11-2011, 07:31 PM
I have many propane generators at work and when the temps drop much below freezing the tanks frost up while the unit is running. The generator will usually shut down sometime afterwards. We have found that using tank heaters solved the problem.

A bunch of GI's, in Fairbanks, AK, thought the propane heaters was just the ticket to keep your engine warm when there no places available to plug in the automotive heaters...they worked until the outside temps hit -20 or below...the propane quit flowing..and a BUNCH of guys came out of the movie to find their engines frozen. The theaters in Fairbanks usually have a long intermission during the movie just so people can go outside to run the engine to prevent freeze up. I've got all kind of experience with automotive tank heaters, electrical cable and some primo experience in winterizing cars and trucks

pmmjarrett
02-11-2011, 08:34 PM
LP will freeze and boil. At 22F you were well above the boiling point.

Freezing point is -310*F
Melting point is -306*F
Is a liquid at -50*F
Boiling point is -44*F
Flashpoint is -156*F
Autoignition temp in air is 920 - 1020*F
Max burn temp 3595*F
Cornfuzed yet.

Here's the state of LP..... At -312F and below it is frozen. Between -312F and -306F it is in transition, it's either melting or freezing. Between -306F and -50F it is a liquid. From -50F to -44F it is again in transition, either vaporization or condensation. At -44F it is boiling and turns gas.

Now for fire safety.... At -157F and below it won't burn without help. At -156 and above it will burn on it's own if ignited. It will sponaeously ignite in air at temps of 920F - 1020F and burn as hot as 3595F

2psnapod2
02-11-2011, 09:17 PM
It takes a 15.5% propane to air ratio to burn. So if you had a room full of it, go ahead and light up. If you wish. Natural gas is 17.2. I would rather be in a full room of it, but on the other end you could not breathe so have a tank of air with you. I used to work for a company to sold it. Just have to be careful. That's all.

pmmjarrett
02-12-2011, 01:15 AM
It takes a 15.5% propane to air ratio to burn. So if you had a room full of it, go ahead and light up. If you wish. Natural gas is 17.2. I would rather be in a full room of it, but on the other end you could not breathe so have a tank of air with you. I used to work for a company to sold it. Just have to be careful. That's all.

15.5% is for a perfect 100% burn of propane and oxygen in an internal cumbustion engine called the stiochiometric ratio.

The flammability limits for propane in air like in a room is 2.2 - 9.5%, the explosive limit is 9.5 - 10.1%