G2 Gas Fitter Practice Exam

What type of sensors do most underfired storage water heater temperature controls utilize?

1. Rod and tube sensors

2. Thermocouple sensors

3. Infrared sensors

4. Fluidic sensors

The correct answer is: Rod and tube sensors

Most underfired storage water heater temperature controls utilize rod and tube sensors because of their design and functionality for measuring temperature effectively in water heating applications. These sensors typically consist of a metal rod that contains a bimetallic strip or a thermistor, which can respond quickly to changes in temperature. Rod and tube sensors are widely utilized in this context because they provide accurate and reliable readings necessary for maintaining optimal water temperatures. They are also durable and can withstand the conditions prevalent in a water heating environment, including exposure to moisture and high temperatures. This makes them suitable for the continuous regulation required in underfired storage water heaters, helping to ensure efficiency and safety during operation. Thermocouple sensors, while another common type in various applications, may not provide the same level of responsiveness or durability in water heater settings compared to rod and tube sensors. Infrared sensors, typically used for non-contact temperature measurements, are not suitable for direct temperature regulation in water heating systems. Fluidic sensors, on the other hand, are more associated with measuring fluid movement or pressure rather than temperature.