What is the appropriate instrument for measuring carbon dioxide levels?

The appropriate instrument for measuring carbon dioxide levels is a combustion analyzer. This device is specifically designed to assess the efficiency of combustion processes and analyze exhaust gases, including the concentration of carbon dioxide. It provides valuable information regarding fuel combustion efficiency, air-fuel ratios, and emissions.

Combustion analyzers often use infrared sensors to detect specific gases like CO2, making them particularly effective for this purpose. They also help in diagnosing issues in heating systems, ensuring regulatory compliance, and optimizing performance, which is crucial in residential and industrial applications.

In contrast, the other instruments mentioned serve different purposes: a manometer measures pressure, an anemometer is used for measuring air velocity, and a draft gauge measures the pressure difference across an enclosure to assess airflow. None of these instruments are designed for direct measurement of carbon dioxide levels.