Gas Fitter Practice Test

Which component can function as a pilotstat?

1. A pressure gauge

2. A gas valve

3. A safety limit switch

4. A control module

The correct answer is: A gas valve

The correct answer is that a gas valve can function as a pilotstat. A gas valve plays a critical role in regulating the flow of gas to the burner and ensuring that it stays ignited. Specifically, certain types of gas valves include an integrated pilotstat function, allowing them to sense the presence of flames or pilot lights. When the flame is detected, the pilotstat keeps the gas valve open; if the flame goes out, it will close the valve to prevent gas from leaking, thereby enhancing safety. This function is essential in gas appliances, helping to maintain safe operations while providing the necessary control for the gas flow. Other components listed, such as a pressure gauge, safety limit switch, and control module, do have critical roles in gas systems but do not directly function as pilotstats. A pressure gauge measures the pressure of the gas but does not have sensing capabilities for flame detection. A safety limit switch is designed to interrupt the circuit if unsafe conditions arise but does not manage the gas flow directly. A control module acts as an overarching interface for appliance operation but, like the other components, lacks the specific function of acting as a flame-sensing device like a pilotstat.