Rick, normally when you want to disconnect a tank (usually to refill), you have to do a couple of things:
- Turn the auto-changeover valve so that it points to the full tank. You may have to look at the hoses to see which one connects to the full tank.
- Go to the empty tank and close the valve on the top of the tank.
- Disconnect the pigtail that connects the empty tank to the LP system.
If there's a little pressure in the line, a small amount of gas will be released (from the pigtail) when you disconnect. It should stop in a second or two. If gas is coming out fast, and doesn't stop, you may have the changeover selector pointed the wrong way. If gas is leaking slowly, and doesn't stop, you may have a problem with the changeover valve.
There should be no leakage from the tank. If the tank leaks when the valve on the top is closed, it needs to be fixed or replaced.