Can a propane gas Gage vary between 10-15% of what is really in the tank?
When we fill propane tanks we use a “fixed liquid level” gauge. This is a valve that has a tube that extends down to the 80% level of the tank. We open that valve and pump liquid into the tank until liquid appears at the valve outlet. We only fill to that point to allow room in the tank for the liquid to “grow” if the temperature outside increases. This is a precise filling level, and the only LEGAL method of filling tanks. Don’t confuse this with portable grill cylinders. The gauge you are asking about is a float gauge with an arm extending down into the tank and a float that rotates a magnetic dial as the liquid level rises or drops. It is not a precision gauge. It is only there to give you a rough idea of how much liquid is in the tank. A few things cause these gauges to be inaccurate. Wear of the gauge itself is one thing. Another cause that is pretty common, but not necessarily right, is that if the person who last refit that tank didn’t have the correct gauge on hand, they may ha
