The yellow valve is used to adjust the gas pressure, and the clockwise pressure is high, but the counterclockwise pressure is low. Figure 2 shows the gas switch at the burner. The steps to light it are: 1 First turn on the gray gas cylinder switch behind the yellow switch, and 2 light a piece of paper at the burner (or a special igniter, like the current plastic lighter, can extend a long tube for more than ten yuan, light the igniter and put it on the burner. ) Turn on the switch in Figure 2 again, and gradually increase the opening point.