How Does a Gas Water Heater Tank Operate?
There are several types of gas water heaters. You can choose from heaters with or without a tank. Heaters with a tank come with the options of natural or proprane gas. Standard tanks are 50 gallons in size, but range from 40-80 gallons. Most homes have heaters with a tank.
There is a pilot light at the bottom of the water heater tank. The flame is kept lit by a small amount of gas flowing to a thermal coupling. When you change the thermostat temperature to a higher degree, or if the sensors read a lower temperature than what is desired, the gas exchange valve opens to allow gas to flow into the burner assembly. The increased gas flow is usually at 10 psi (pounds per square inch). The burner assembly uses the gas to create thermal energy at the rate of approximately 40,000 BTUs. This energy is what heats the water. Once the sensors have a reading of the temperature that is desired, the gas exchange valve will close to prevent the gas from reaching the burner assembly.
There are two points of importance that you should know about the operation of the water heater.
- The heater emits harmful gases that should be piped to exit the house with a triple-wall galvanized pipe.
- Raising the desired temperature above a safe setting, which is indicated on the tank, will cause the temperature and pressure valves to release. The tank can combust if it is not properly installed with a thermal expansion tank.