Originally Posted by Smitty
Paul nailed it, the LP doesn't care, but an absorbtion refrigerator would. However the tanks need to be oriented correctly, meaning you can't lay a grille tank on it's side.
Most portable LP tanks are vapor withdrawl tanks, industrial tanks for mobile equipment and/or permanent mounting in a vehicle can be either liquid or vapor withdrawl, if your appliances require vapor and you feed them with liquid gas you are at risk of creating a bomb.
The most common misuse is when someone tries to use a forklift LP bottle (liquid, pickup on the bottom)to supply a portable space heater (vapor,pickup on the top) if you invert the bottle you effectively chancge it to a vapor bottle and the heatern will function properly
Typically LP vehicles use a liquid supply system and then use engine coolant to vaporize the fuel before it is fed to the engine, the lp engines will run in any position and also run with considerably less emissions and only about a 10% power loss.