We all are familiar with gas cooking tops by now, but have you ever wondered how they work exactly. I myself for one wanted to find out more about this great substitute for the ever temperamental electricity situation. Let us dive into the workings of gas cooking.
An electric gas stove burner consists of a burner assembly attached to a small gas valve that is connected to the main gas line. When you turn the knob, the intake valve opens and gas flows through a venturi tube, a wide pipe that narrows in the middle. Gas enters through one of the wide ends, and as it passes into the narrowed section, its pressure increases. There is a small air hole in the section where the pipe widens again, and as the gas moves into this section, the pressure releases, sucking oxygen into the air hole. The oxygen mixes with the gas, making it combustible. The oxygen-gas mixture then flows into the burner.
The burner is simply a hollow metal disk with holes punctured through its perimeter. A gas pilot light or electric pilot sits to one side of the burner and sends a small flame or spark to ignite the oxygen-gas mixture as it flows through the holes in the burner. By turning the knob to a higher heat setting, you increase the flow of gas and air, and the flame gets larger.
Gas burners can work with either natural gas or propane. Both are hydrocarbon fuels, and their hydrogen content makes the gas flame appear blue. A yellow or orange flame indicates an excess of oxygen and a slightly cooler temperature. The orange colour comes from unburned carbon. It’s natural for the tips of the flames on a gas burner to appear yellow-orange where the flame is cooler, but if the entire flame appears yellow, the ratio of gas to oxygen is too low, and the gas burner or intake valve may be clogged and need cleaning. A red flame is cooler still and typically causes soot (unburned carbon) to appear on the bottoms of pans.
This was very informative and helps my understanding of gas cooking!