Installing an HVAC system is a complex operation. Your HVAC technician has to evaluate the physical space available, decide on the type of duct configuration that works best, assess the thermal characteristics of your home and take into consideration the performance ability of the system being installed. Properly sizing the ducts for your new equipment is sometimes overlooked, but it is a critical element of a quality HVAC-system installation.

The ductwork in your heating and cooling system must be properly sized to distribute the conditioned air generated by your air conditioner, heat pump or furnace. Conditioned air must be able to reach all vents and registers in your home, particularly those at points farthest from the HVAC unit.

If the ductwork is too small, it will not be able to carry enough heated or cooled air to keep your home at the temperature you prefer. Small ductwork also restricts airflow the system needs to function properly. You can see your HVAC system as a large air circulation mechanism that constantly moves air in and out of your home; if that circulation is disrupted or blocked, the system won’t work as it should.

Ductwork that’s too large, on the other hand, slows air velocity, wastes energy and causes your utility bills to rise.

To ensure that you have a system that’s correctly sized for your home, your contractor should do a Manual J calculation to determine heat gain and loss in each room. Your contractor should also do a Manual D calculation if your home is new or if you need a significant ductwork redesign. Both manuals are published by the Air Conditioning Contractors of America and are considered the industry standard.

Rheem Pro Partner is the Denver area’s reliable source of home comfort and equipment sales, maintenance and repair. Contact us for more information on duct sizing and design.