To adjust you MUST have a LP pressure MONOMETER, connected to the LP system and you CANNOT connect it to a stove range burner. The LP pressure(NO LOAD) is set at 11.5 inches water column. You then turn on the furnace and water heater and see what the pressure drops to. It should NOT drop below 11 inches with a large 50% load. The rating of a LP regulator is about 200,000 BTU's. The furnace will pull anywhere from 20K to 45k depending on the model. The refer is minimal. The Stove range will be 5600 to 9000 for the burners and I believe the Oven is about 7000 btu. The precision temp is about 55,000 btu's. A standard water heater is about 9000 btu's. Doug