Equally efficient heating and cooling modes in one system

Overhead ductwork has long been favored for HVAC air distribution due to its convenience, aesthetic appeal, and effectiveness. However, it faces challenges in maintaining efficiency for both heating and cooling purposes, as warm air naturally rises and cool air falls. A versatile solution for various seasons and temperature transitions is needed to ensure occupant comfort throughout the year with efficient temperature control.

Billy Farr

Engineering Sales Manager, North America


Designed for Cooling and Heating

Innovative fabric-based HVAC solutions like FabricAir’s VarioDuct can address these challenges. Fabric duct manufacturers have developed new air dispersion solutions that project air upward for cooling and downward for heating.  These specially designed ducts combine multiple flow models, air volume requirements and air pressures within the same duct. The innovation that allows this is an internal damper-like mechanism made of an attached piece of fabric that runs the entire length of the duct. Depending on the cooling or heating requirements, the damper adjusts to align the interior fabric to the top or bottom of the duct.

Custom-Engineered Airflow

When heat is needed, the internal fabric damper is positioned to the top. This configuration allows the supply air to push the internal damper against the top of the duct, effectively blocking any orifices from emitting airflow through the upper half. The upper half of the duct features micro-perforations, which enable high air changes at a lower velocity. As a result, supply air flows through the bottom of the duct’s orifices. Alternatively, the bottom half of the duct can utilize jets, nozzles, or larger orifices to accelerate the heated air downward or laterally, ensuring uniform air dispersion in spaces even with high ceiling systems. This damper/fabric process can also be applied to horizontal elbows, reducers, and concentric transitions, enhancing the overall efficiency of the HVAC system.

Easy to Control

Cooling and heating transitions are activated by an optional thermostat or a third-party actuator that communicates with a building management system (BMS) via a network. This automation ensures smooth and efficient switching between heating and cooling modes. Furthermore, fabric duct systems often include a manual crank as a standard feature, providing redundancy during potential power outages.

Ideal Applications

Combination heating and cooling ducts are particularly well-suited for open office areas, classrooms, production facilities with high temperatures generated by machinery, and large occupied spaces where precise temperature control is important. Areas with high ceilings also benefit from the internal damper, as it ensures more uniform heating throughout the space. These systems prove especially valuable during transitional periods characterized by significant outdoor temperature swings throughout the day. Such spaces typically require heating in cool mornings and evenings, but air conditioning during the warmer parts of the day.

Fabric ducts offer an innovative and efficient solution for HVAC air distribution, overcoming the limitations of traditional overhead ductwork. By precisely directing airflow and optimizing temperature control, these systems enhance comfort and energy efficiency in a variety of settings. Whether it’s an open office, a classroom, or a production facility, custom-engineered fabric ducts provide reliable and versatile heating and cooling capabilities.

Additional Information

Learn more about Varioduct, FabricAir’s heating and cooling solution

Learn more about innovations from FabricAir

FabricAir® VarioDuct™ – two airflows in one duct – YouTube

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