A BBQ pressure regulator refers to the gas pressure regulator that attaches to your LP or propane tank. This device sends gas under pressure to your burners, which can then be controlled using the cooking knobs on the front of your grill. In many cases, gas pressure regulators are pre-set at the factory and no adjustment can be done by the consumer. However, on high end or commercial BBQ grills, the regulator does have an adjustable knob that can be adjusted to achieve perfect flame height and heating temperature for any cooking occasion.
Locate your BBQ gas pressure regulator. It will be a small metal saucer-shaped object found on the gas line directly next to the gas tank connecting nut. If there is not a turning knob on the regulator, it is pre-set and sealed from the factory, and cannot be adjusted.
Turn the LP gas tank handle all the way on and allow the gas to flow normally. Turn the pressure regulator all the way on. Turn a burner control knob to the "start" position, then light that burner in the accepted way, either electronically or with a lighter.
Turn the burner all the way up to maximum, then begin to adjust the knob on the regulator by turning it down. Watch the flame on the burner. As soon as it begins to lose pressure and the flame begins to subside, stop turning the pressure regulator down. At this point, the pressure will be correctly set.