HVAC manufacturer finds a cool solution with HVLS fans

Industrial-grade large diameter ceiling fans spun into existence a decade ago, offering an energy-efficient, cost-saving method for circulating massive amounts of air within large facilities.

September 1, 2009

McQuay International’s Applied Air Systems division in Faribault, MN had a debilitating problem with regards to air movement within their plant: stale, stagnant air was leading to worker discomfort, severely affecting productivity. What this HVAC giant needed was fans, large 24-ft. diameter high volume low speed ceiling fans to improve air circulation and increase worker productivity once again.
McQuay, the world’s second largest heating, ventilation and air conditioning company, has taken advantage of the ability to slowly move great volumes of air over large areas, reaching every worker on the production room floor.
The installation of these large ceiling fans has been a positive experience. "Prior to the purchase of our fans, there was a major [air] circulation problem," said Jim Douda, facility engineer at McQuay’s Fairbault plant. "We had several 52-in. box fans around the plant, but that did not help because there was no set pattern," he said.
When you get right down to it, McQuay personnel felt they had enough air, yet it was insufficiently distributed and created a crowded, noisy and messy work environment. "One of the biggest concerns when choosing to install these fans was safety," he added, referring to the numerous box fans littering the plant floor. Douda purchased a dozen 24-ft. diameter fans for McQuay’s 120,000 sq. ft. facility, allowing this air conditioning giant to get back to the business of cooling.
Unique engineering
Industrial-grade large diameter ceiling fans spun into existence a decade ago, offering an energy-efficient, cost-saving method for circulating massive amounts of air within large facilities such as McQuay. "Thousands of working environments in facilities worldwide have been improved while reducing annual energy consumption, when compared to large numbers of small, noisy fans," said Paul Lauritzen, director of sales for The Big Ass Fan Company, Lexington, KY.
In-depth engineering coupled with industrial design and expertise in aerodynamics have allowed for technological advances of the fan components to ensure longevity and durability. "We have found that the best tool for materials and design analysis to be the use of computer simulation verified by physical laboratory testing. This combination has enabled us to specify the best alloy, heat treatment and design configuration for each component to ensure the best possible performance and durability of the end product," said Richard Oleson, engineering manager for Big Ass Fans.
Unlike small, high velocity fans that create small turbulent air streams which dissipate quickly, a 24-ft. diameter high volume, low speed fan uses a 1 hp to 2 hp motor with specially designed blades to move a vast amount of air very slowly. The air current from the fan approaches floor level in a cylindrical column of a size equivalent to the fan’s diameter, turning into a horizontal jet radiating out in all directions.
It’s these small motors that contribute to the fan’s success in reducing energy cost and consumption by allowing thermostat settings to either be raised or lowered without affecting worker comfort.
This energy reduction is achieved during the cooler months by moving warm air gathered at the ceiling level back down and circulating it throughout. Thus, facilities are able to warm a building’s interior in a fraction of the time, significantly reducing the thermostat setting needed to maintain comfort and uniform temperatures. During summer months, the fan’s gentle breezes dehumidify the air and maintain a comfortable, cool feeling by evaporating moisture off the skin’s surface.

A rise in productivity
While originally interested in a solution to plant safety and air movement concerns, Douda was delighted that McQuay’s fans greatly increased employee morale. Appreciating the delicate balance between facility temperature and worker production, Douda recognized the value in promoting a comfortable working environment. "Now, no one complains about items such as circulation, dead areas, and noise. I have to say that productivity has gone up," he added. In fact, studies have shown that occupant comfort leads to increased productivity. These studies indicate that worker productivity decreases by one degree for every 0.9 degree Fahrenheit increase in temperature above 77 degrees Fahrenheit.
According to the National Bureau of Standards, energy savings of at least 3% can be achieved for each degree the thermostat is lowered during the heating season or raised during the cooling season. If a facility owner using a large low speed ceiling fan is able to adjust the thermostat five to eight degrees, energy savings would be 24% or more year-round. Moreover, the operating cost is negligible compared to the costs of heating and cooling using conventional HVAC systems.
"Using large circulator fans as the first stage of cooling or only method of cooling occupants provides an opportunity for significant energy savings," said Christian Taber, applications engineer and LEED accredited professional for Big Ass Fans.
McQuay International now enjoys a consistent temperature year-round, employees are comfortable and energy bills are reduced by eliminating the wasteful box fans. "They have absolutely been put to good use here at our facility." Douda said. "We saw that the employees were concerned before; now, they receive a high level of satisfaction and a more comfortable working environment from these fans."