Air Balancing HVAC Systems

Methods of Air Balancing

Air balancing a distribution system is needed to properly direct the air flow in order to optimize the system’s design. Flow rates are tested, adjusted, and balanced as cubic feet per minute (CFM) or cubic meters per hour (m3/h). There are two traditional methods for balancing airflow at the terminals. The first is sequential balancing, which involves setting the zone and branch dampers in sequence. However, the most common method of air balancing is called proportional balancing.

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Non-Dispersive Infrared, NDIR, Carbon Dioxide Sensors

Non-Dispersive Infrared, NDIR, CO2 Sensors

Dwyer offers several carbon dioxide measuring products that use non-dispersive infrared sensors as the sensing element. Carbon dioxide sensors are commonly used in building automation systems to monitor air quality.  The level of carbon dioxide is indirectly proportional to the amount of people in a space and can be used to adjust ventilation for the space.


There are two basic types of gas sensing technologies: chemical reaction and infrared spectroscopic. Most chemical reaction sensors are electrochemical sensors, which are not as reliable as they can interact with multiple gases and wear from interaction with the gas. Continue reading “Non-Dispersive Infrared, NDIR, Carbon Dioxide Sensors”

The Dwyer Approach to Monitoring Relative Humidity in Stagnant Air

Have you ever been in an office, classroom, or hospital room where you change the wall mount humidity/temperature sensors that are integrated into a building automation system (BAS) and felt little to no change in the space? Worse yet, have you  ever seen two sensors side by side reading different humidity values? Humidity and temperature sensors are manufactured by numerous companies and many of the occupants adjusting the settings or monitoring the current levels feel that the sensors are unreliable or have a poor accuracy. Continue reading “The Dwyer Approach to Monitoring Relative Humidity in Stagnant Air”