Adjusting liquid propane pressure requires an end-line pressure gauge as well as the owner's manual for the particular tank or furnace being used. Turn the propane tank off while adjusting the pressure.
- Locate and turn off the pressure regulator
Find the control knob on the pressure regulator connected to the propane tank. Make sure the knob is turned to the Off position.
- Turn off the furnace, and test the pressure
Go to the furnace, and turn the knob on the control panel to the Off position. Next, use an open-end wrench to remove the fitting where the gas line connects to the control box. To test the pressure, screw the fitting into an end-line pressure gauge. You should find the manufacturer's recommended pressure in the owner's manual; it also often appears on a label near the control box.
- Regulate the pressure
Turn the control knob on the regulator to the recommended pressure. Next, reference the pressure reading on the gauge. If it is too high or too low, adjust accordingly. Once the pressure is regulated, make a corresponding reference mark on the knob, and then turn it off.
- Reattach and reset your propane
Detach the gas line from the gauge, and reattach it to the control box. Turn the regulator knob to the correct setting. Finally, turn the control knob to the Pilot position, and wait five minutes before lighting the pilot light.