In a competitive auto retailing economy, car dealerships always look for a competitive edge and Mel Grata Chevrolet/Toyota has found climate-controlled indoor air comfort greatly improves customer satisfaction especially during cold Pennsylvania winters.
Instead of fighting inclement weather, Mel Grata customers now drive-through one of two new climate-controlled, service/staging areas featuring doorway air curtains. The air curtains, also referred to as “air doors,” efficiently separate the indoor/outdoor environments and maintain indoor temperatures especially with perpetual door openings during morning rush hours.
The Chevrolet service area was expanded into a 2,000-square-foot, newly-remodeled three-bay space. The separate 1,500-square-foot Toyota service area is a recently-built two-bay, four-door space. Both buildings adjoin the main 75,000-square-foot dealership’s showroom and offices complex. Industrial Direct Drive 12 Series air curtains with three-speed motors manufactured by Berner International, New Castle, Pa., seal each of the seven 12- by 12-foot doorways with a controlled airstream to protect against outdoor air infiltration during hundreds of daily door cycles. “Without the air curtains, it would take several minutes for the heating system to recover our 70 F set point temperature that keeps customers and employees comfortable from outdoor elements,” says president Mel Grata who conceived of the idea after seeing air curtains in action on trucking docks slips, vestibules and retail stores entrances. “With the air curtains, the temperature doesn’t fluctuate much when doors open.”
Besides creating a comfortable environment, the air curtains are projected to pay for themselves within two years in energy costs, according to a Berner energy audit. The savings accentuate the dealership’s green construction efforts that also included high-efficiency HVAC systems and recycled building materials. Enough green strategies, including the air curtains, have been instituted into the two service buildings that the project potentially could have potentially earned a Leadership in Energy and Environmental Design (LEED) certification, which is a current trend in auto retailing today, according to Grata.
Berner International’s sales staff was instrumental in training the HVAC contractor, General Maintenance Contractors, New Castle, Pa., and Grata’s maintenance staff on a coordinated installation effort. For example, the mechanisms and rails of overhead doors common to service bay operations can be problematic by obstructing air curtain discharge. Therefore, Berner wall and extension brackets allow the air curtains to be installed far enough away from the wall and past the door track as to not impede door rollups, but still maintain the proper volume, velocity and uniformity (VVU) that is critical to doorway air sealing performance.
How Air Curtains Work
Air curtains consist of a metal cabinet that’s typically mounted above the length a doorway. Air is drawn through the air intake and accelerated by a fan into a plenum and distributed along the full length of the discharge nozzle. The nozzle and their aerofoil-shaped vanes’ angle are critical for creating a uniform air stream and minimal turbulence. Proper air discharge creates a jet stream that meets the floor near the threshold where approximately 80 percent of the air is returned to the building. Sizing an air curtain is critical to proper performance. Sizing factors include door dimensions, type of use, climate, prevailing winds, exterior temperature and building pressurization.
Accurate manufacturer performance specifications are also critical to efficacy, therefore General Maintenance Contractors chose air curtains certified by the Air Movement and Control Association – International, Arlington Heights, Ill., (AMCA), a trade association dedicated to certifying manufacturers’ air performance statistics on all types of air movement devices, including blowers, fans, motors and air curtains.
AMCA performance certification combined with Berner’s standard in-house powder-coating with colors aesthetically matching Chevrolet and Toyota corporate colors in the interior design helped steer Grata away from another air curtain brand, according to Arthur Arena, president, General Maintenance Contractors.
Mechanical Contractor’s HVAC Design/Build
The systems that provide the heating and air conditioning environment that the air curtains help preserve were design/built by General Maintenance Contractors, which specializes in commercial HVAC and refrigeration.
The Toyota building, which includes service, waiting area, offices and other rooms, features four high-efficiency packaged HVAC rooftop units by the Luxaire division of Johnson Controls, Norman, Okla. They range from 4 to 7.5 tons and include 180,000-BTU gas-fired heating. For additional air comfort near doors Arena also specified and ceiling-mounted three 100,000-BTU HeatStar tube-style radiant heaters by Enerco, Cleveland, Ohio.
The Chevrolet building has a similar arrangement of packaged rooftop units and radiant heaters. A temperature controller by Honeywell, Minneapolis, Minn., controls all the equipment and maintains temperature through energy-efficient staging programmed by General Maintenance Contractors.
The project has created a comfortable and very aesthetic environment to bring cars and authorize service arrangements while also efficiently using energy. “We’ve had no air comfort complaints from customers or employees even on the coldest winter days, and that’s good for business,” says Grata.