When air balancing is correct, your HVAC ductwork distributes the appropriate volume of cooled or heated air to each room according to its size and returns an equal amount back to the A/C or furnace. When air balancing is out of whack, you’ll notice symptoms such as certain rooms getting too much cooling or heat—usually the ones located closest to the system blower—while rooms far away or upstairs don’t receive enough. Over time, a balanced home may become gradually unbalanced due to aging of the structure, renovation or remodel, ductwork issues or an upgrade to the HVAC system.
Not Too Much or Too Little
Both positive pressure (too much supply air for the return flow) and negative pressure (not enough supply air for the return flow) represent pressure imbalances that impact energy efficiency, heating and cooling consistency and indoor air quality. The optimum balanced result is a condition of neutral air pressure in each room.
A professional air balancing procedure requires specialized equipment to measure airflow into and out of rooms at supply and return grilles, the static pressure inside the ductwork and the temperature at strategic points in the system. Small doors inside the branch ducts conveying air to individual rooms are called volume dampers and control the cubic feet of air delivered to the room per minute. Adjusting these dampers alters the air balance in the affected room.
A Sense of Balance
Since balance in the system changes slightly every time the volume of airflow into any individual room is altered, balancing is a precise skill that requires room volume adjustments in a specific sequence, as well as repetitive re-testing of other rooms as adjustments are made. In addition, other factors that influence proper air balance, including air leaks in ductwork, structural modifications and the condition of the blower fan may need to be addressed, as well.
For information on professional air balancing services for your home in Calgary, contact Arpi’s Industries.
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