LP Fill Fail

msmith1199 wrote:

Vapor is supposed to come out. You can't fill a pressurized tank with a liquid gas without giving the air someplace to go and it goes out that valve. That bleeder valve gets opened and as you fill the tank you can hear the hiss from the vapor (air with a propane smell to it) coming out of that valve. When the first sign of liquid appears then the tank is full. That's why you don't smoke while filling the tank with propane. Everything sounds perfectly normal to me.

Once a new tank has been initially purged, there should not be any air in it unless it has been emptied and the service valve has been left open. The gas that comes out of the open liquid level gauge (commonly misnamed the "vent" or "bleeder") is just that, propane gas until the liquid level reaches the valve at the 80% full point. And an LP tank can be filled without opening the liquid level gauge, but then you're depending on the overfill prevention device (OPD) to shut off the flow at the proper level, instead of it acting as a safety backup as intended.

I suspect the OP's problem may be related to either a missing gasket on the fill port, with the leaking gas escaping close enough to the liquid level gauge to mask its origin, or the operator failed to close the pressure relief vent on the fill nozzle.