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
US
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
FAQ
Heating and cooling require different airflow strategies because warm and cool supply air behave differently in a room. A system optimized for one mode may therefore provide less effective distribution in the other unless airflow direction and throw are adapted to the operating condition.
Related terms: heating and cooling, overhead air distribution, seasonal HVAC, air throw, flow models, temperature control
VarioDuct uses an internal membrane to separate two airflow patterns within the same duct. A damper moves the membrane between positions, allowing the system to use the appropriate flow model for heating or cooling without installing two separate duct systems.
Related terms: VarioDuct, dual airflow, internal membrane, heating and cooling, airflow direction, seasonal HVAC
The VarioDuct damper can be operated manually or automatically with a motorized actuator. It can also be integrated with a room sensor or building management system, allowing the airflow mode to change as operating conditions change.
Related terms: VarioDuct control, BMS integration, motorized actuator, room sensor, heating mode, cooling mode
VarioDuct can be useful in buildings that require both heating and cooling from overhead air distribution, particularly spaces with changing seasonal conditions, high ceilings, or varying internal heat loads.
Related terms: year-round temperature control, high-ceiling buildings, commercial HVAC, production facilities, dual-mode air distribution
Learn more about FabricAir VarioDuct.
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