The needle on my CO2 Regulator hardly moves – is this a fault?

A Carbon Dioxide regulator has two gauges – a low pressure gauge that tells you the amount of pressure being supplied to the keg and a high pressure gauge that reflects the pressure in your gas cylinder.

The high pressure gauge rarely moves and just tells you whether you have gas in the cylinder, or whether it is empty. The reason for this is that the carbon dioxide in the tank is in liquid form, as CO2 liquifies at a relatively low pressure/temperature intersection. So if your high-pressure gauge hardly moves above the red on your CO2 regulator, this is not a fault.

This is different to a mixed-gas or nitrogen regulator, as nitrogen is not liquid under pressure, so the high pressure gauge on a nitrogen regulator is a good indicator of remaining gas within the tank.