HVLS fans are quieter, are less disruptive and consume less energy than traditional, high-speed ceiling or floor fans
Airplane hangars are tall, long and usually made from metal. While that’s great for the aircraft being stored in them, these unique designs lead to several facility management challenges. These challenges include energy costs, temperature control, air quality and safety/comfort issues. In an effort to mitigate these challenges, more and more hangar owners are installing high-volume, low-speed (HVLS) fans. HVLS fans can significantly improve the comfort and health of pilots, guests and mechanics. On top of that, they can save building operators substantial amounts of money by making existing heating and ventilation systems more efficient, while providing additional benefits in buildings with no air conditioning.
HVLS versus other types of fans
High-speed ceiling or floor fans can help increase air movement, but they have several disadvantages when compared to HVLS ceiling fans. HVLS fans can move larger volumes of air; a single fan can cover an area up to 22,000 square feet; and can replace as many as 10 to 20 floor (or smaller) ceiling fans.
HVLS fans are quieter, less disruptive and consume less energy than traditional, high-speed ceiling or floor fans. Reducing the amount of floor fans can reduce clutter on the ground and minimize the chance of an accident.
HVLS complements HVAC
The key to HVLS fans is that their long blades (up to 24-foot total fan diameter) spin much more slowly than a traditional ceiling or floor fan. Their unique blades are specially designed to capture the maximum amount of air possible and push it softly to the floor.
In the summer, the gentle breezes created by an HVLS fan keep employees and visitors cool by quickening the evaporation of sweat. In winter, in a process called destratification, the fans take the warm air created by an HVAC system and pull it down from the ceiling to the floor level, allowing people inside to be more comfortable with a lower thermostat setting. Energy savings add up
A 24-foot diameter model uses 1,500 watts per hour for cooling and as little as 100 watts for destratification, making HVLS fans extremely energy efficient. This translates to operating costs of as little as a few cents per hour. During the winter months, HVLS fans can reduce energy consumption by up to 30 percent. When used to supplement air conditioning, the fans help lower the perceived temperature- which means thermostat set-points can be raised. Because energy costs are reduced roughly 4 percent for every degree the set-point is raised, a 3 to 4 degree increase in the set-point can reduce energy consumption by 12 to 16 percent. With year-round use, HVLS fans can pay for themselves in as little as six months.
Advantages of HVLS in hangars
Many advantages of HVLS fans are even more pronounced in airplane hangars due to the way they are constructed and the material they are made from. Most hangars are made from metal, several stories tall and one big, wide-open space. A higher ceiling coupled with a large, open area usually leads to temperature inconsistencies throughout a building. HVLS fans are capable of covering a large area and those benefits are only more pronounced in taller buildings, as the cone of air it pushes toward the ground only widens. The fact that metal conducts heat extremely well only adds to the need for the benefits that HVLS fans provide: destratification and a light, cooling breeze. One not-so-obvious advantage of HVLS fans is that they deter birds from flying into and nesting in hangars, even when they are open to the outdoor elements.
Controlling SSS and SBS
Sweating slab syndrome (SSS) occurs when moisture intermittently develops on the surface of an interior concrete slab. SSS can increase the slipperiness of the concrete surface and pose a serious risk to people who walk on it. When warm, humid air enters the structure through open doorways, windows and vents, it will condense on any surface that is at or below dew-point temperature- often the floor surface. This often occurs in spring when cool evenings are followed by warm mornings. HVLS ceiling fans can help reduce or eliminate slab sweating by minimizing ceiling-tofloor temperature differentials and increasing the surface evaporation rate.
Sick building syndrome (SBS) is when building occupants experience acute health and comfort effects that appear to be linked to time spent in a building, even though specific causes can’t be identified. Most affected people have clinically identifiable symptoms (headache, dizziness, nausea) and typically feel better soon after leaving the building. Increasing ventilation rates and air distribution through means like HVLS fans often can be a cost-effective means of providing additional air flow, while also reducing indoor pollutant levels that can build up in ventilation systems.
Andy Olson is the marketing manager for Rite-Hite HVLS Fans, Milwaukee. To learn more, visit www.ritehitefans.com.