Oil in a propane line?

[ishgood]

I have a propane extension hose that connects to a 20lb tank on one end and whatever a 1 lb bottle would fit on the other end, lantern, buddy heater, etc.

Today I disconnected the tank end and a an ounce or so of oil shot out of the end along with the propane that was still in the line. The line had an ounce or so of oil in it.

Anyone ever had this happen?

Im wondering where the oil would come from. Its some kind of light clear oil. Nothing was connected to the accessory end at the time but the last thing connected was probably a buddy heater.

Thanks.

[CAMAN]

All propane comes with a small bit of oil mixed in with it from the refining process. A lot of oil in propane is usually caused by repeated overfilling of the tank. This is the reason it is recommended to put a filter on the line if you don't have a regulator installed while using a buddy heater, the oil will damage the unit.

There really is no fix for it except replacing the hose and installing a filter on the line. You will never get all the oil out of the hose to guaranty that it won't damage your unit.

[slipperybob]

That oil also seems to really like to collect in the hose.

[Ice Chicken]

Shutting the tank off and burning the gas left in the hose should solve the problem.By leaving high pressure in the hose with the change in temperatures since you last used it may have caused the vapor in the line to change back into liquid form causing the oil.

[merkman]

high pressure in the hose

+1

From my understanding (I think airjer is the subject matter expert though) the high pressure forces the "oil" out of the hose.

Use a regulator before the hose to reduce the pressure and eliminate the "oil" from showing up or a filter after the hose to filter the "oil" once it is there.

[ishgood]

I think you nailed it. The tank valve has been open since last ice fishing season, so its seen a lot of temperature cycles.

Thanks for the info guys.

[Jeremy airjer W]

From my understanding the high pressure forces the "oil" out of the hose.

Use a regulator before the hose to reduce the pressure and eliminate the "oil" from showing up or a filter after the hose to filter the "oil" once it is there.

Actually Icechicken would be the expert!

If you use a regulator you may be setting yourself up for problems with devices that are regulated internally by the device itself. It is absolutely fine using the high pressure hose on those devices. It's not that hard to turn off the tank and let the gas burn off in the hose before shutting of the device/appliance. I have done it this way since I bought my first 20 lb tank and hose for my first buddy heater. I still use the hose and tank today on a variety of devices with no filter and no problems.

There will be a small amount of oil in a new tank from manufacturing. There shouldn't be any extra oil added from the filling process. Overfilling would not make a difference.

[slipperybob]

Propane boils at -45 F so temperature changes need to be below that in order for it to change back to liquid form.

[timjones]

Propane has no odor. I was told by a propane guy this summer that the odor that is added to the propane to make it stink is an oil product. I switched propane companies this summer. I had 40% left in the tank so the new provider set their tank about ten feet from the old tank to do the propane transfer. They set a transfer pump between the two tanks and transferred the gas. Then they moved the old tank out and placed theirs. They then checked everything out for leaks etc. and left. The next day when I got near the tank I could smell propane so I called them up and they sent a guy out to check it. Couldn't find anything wrong but we could smell propane. Found when we got to this one area about five feet from the tank and close to the ground it smelled real heavy of propane. I told him that is about where the pump was sitting and that's when he explained the addition of the odor being an oil base product and said they must have spilled some on the ground disconnecting the pump. Said between the rains and my mowing the grass it would eventually go away. Took about six weeks but it's gone now.

[Surface Tension]

Leaving the tank valve on with hose connected can leech oil from the hose. Most hoses intend for propane are designed not to do this or at least reduce the amount of oil leeched from the hose.

I've had a thick yellowish oily substance that leak from the hose fitting. Even though the connection was tight and no propane leak this crud would ooze from that fitting. Really scratched my head over that one.

In this case it there was the crud in the tank. After the tank was empty I turned the tank upside down and opened the valve. This was an old style tank. This oily crud ozzed out.

Where it came from?

I filled my own tanks off a bulk tank that had a dip tube. My guess is I was picking up the oil that from over many years accumulated the bottom of that tank. Could it be that your supplier has the same problem?

Since then I changed to a new hose and don't fill off that bulk tank.