What is determined by performing an air temperature rise check?

The correct choice relates to the specific measurement taken during an air temperature rise check, which primarily focuses on assessing the performance of the heating system, specifically in how effectively it heats the air being moved through it. The air temperature rise check is conducted by measuring the temperature of the incoming air to the heating system and comparing it to the temperature of the outgoing air.

This measurement indicates whether the system is providing adequate heat transfer. A significant rise in temperature implies that the heat exchanger is functioning effectively, which translates into proper combustion and heat transfer from the burner to the air. If the temperature rise is too high or too low, it could indicate issues with airflow or combustion efficiency, requiring further investigation to optimize the system’s operation.

Other factors, such as flue gas emissions or stack temperature variations, are more closely related to overall system efficiency and safety but are not directly assessed through an air temperature rise check. This specific check is more about ensuring that the airflow across the heat exchanger is correct and that the combustion process is translating effectively into heat.