Gas Fitter Practice Test

What does a barometric damper control?

1. Excess Air

2. Pilot Air

3. Draft Air

4. Ventilation Air

The correct answer is: Draft Air

A barometric damper plays a crucial role in regulating draft in a chimney or flue system, which is essential for maintaining optimal combustion conditions in gas appliances. Its primary function is to control the movement of gases, ensuring that exhaust gases are vented properly, thus allowing the appliance to operate efficiently and safely. In a heating system or similar application, the barometric damper automatically adjusts itself based on changes in pressure. When the draft is too strong, the damper opens to alleviate excess negative pressure, effectively reducing the amount of draft air entering the system. Conversely, if the draft is weak, the damper can close slightly to maintain sufficient draft for proper combustion. This control is vital because improper draft can lead to backdraft, poor combustion, and increased emissions, potentially resulting in system inefficiency and safety hazards. While the other options refer to types of air related to the operation of gas appliances, they do not pertain specifically to the function of a barometric damper. For instance, excess air refers to additional air supplied for combustion beyond what is chemically necessary, pilot air relates to the air needed for pilot lights or igniters, and ventilation air involves the overall airflow to and from a space for safety and comfort. Thus, the choice