Propane regulators are two-stage units that reduce the changing pressure from the storage tank to provide a constant lower pressure using needle valves. They have diaphragms that serve as safety devices to shut off the propane supply if the pressure is too high.
The pressure in the propane tank changes due to the amount of fuel in the tank and the temperature. It is much too high to operate most propane appliances. The first stage drops the pressure to approximately 11 to 15 pounds per square inch. The second stage reduces it to 0.5 pounds per square inch range propane appliances require. While the pressure of a gas exiting a single-stage regulator varies due to the inlet pressure, the two-stage regulator provides a constant exit pressure.
A vent allows access to the atmosphere for the diaphragms. If insects build nests or spiders spin webs inside the vent, it sometimes ceases to function correctly. Owners should check the regulator vent periodically and remove any debris that collect in the opening or on the screen.
Owners should not attempt to repair or adjust malfunctioning propane regulators, professional servicing is required. Additionally, owners should have the regulator inspected on an annual basis to ensure it continues to work correctly.