Oil in propane line

[Deputych]

I was trouble shooting a problem that I was having with the burner on my water heater when I discovered oil in the propane line on the low pressure side of the regulator. I 'm at a loss as to how it made its way into the line. I drained approx one half cup out of the line by lowering the front of the trailer as low as possible. The oil itself did not seem to affect any of the gas appliances in the trailer ( as it turned out my problem was a spider web that had been built in the burner tube). Has anyone else ever experienced this problem? Does anyone have an explanation as to how the oil made it's way into the system?

[TomW]

Pressure vessels (such as your LPG cylinders) are commonly recertified by filling the vessel with oil, and pressurizing the oil to a value well above what the vessel should see in ordinary use. Oil is used instead of air because the results are less dramatic if the vessel should burst.

My guess is that your LPG cylinders still had residual oil in them when they were last filled.

Tom