Why is your gas regulator freezing?

It is normal for the regulator to get cold as the liquid propane turns to gas. If the pressure drop is great enough and the volume is high enough (which is to say, you are doing some serious barbecuing, the temperature can drop below freezing. At that temperature, the moisture in the air will form frost.

If this creates some sort of a problem, you can soak a towel in hot water and lay it on the regulator.