Doors play an important role in your customers’ lives. Closed doors offer benefits like security, privacy and protection against different environments such as temperature, insect, odor, noise and dust, to name a few. And as you know, manufacturers go to great lengths to design doors for virtually every application: they can roll up, slide, fold, or even lift straight up; they can open slowly or fast; they can offer any type of insulating or noise-reducing qualities you need; they can even stop fire and bullets.
But what about when a door is open? It allows egress – obviously necessary in any commercial application -- but what about all those environmental issues (e.g., bugs, temperature, water) they’re trying to protect against by having the door in the first place? The question your customers are probably now asking you is “What can be done to improve the efficiency of an open door?” And if you incorporate air curtains into their product lineup, you have the answer.
According to the 2004 ASHRAE handbook, an air curtain can be up to 80 percent effective in preventing infiltration through an open door – now that’s a powerful selling point.
Plus, many building managers and owners are already familiar with air curtains because they’ve walked under them at their local supermarket, or they’ve noticed them at the back doors of fast-food restaurants, where they are used to keep insects out. But how can manufacturing, warehousing, distribution, food processing and cold-storage facilities benefit from the use of an air curtain? Consider the different types of doors found at these facilities. By installing an air curtain at ground level, on a loading dock, at a cooler, freezer or at man doors — or any other frequently used door within the building that requires environmental control — they can improve the efficiency by up to 80 percent.
Energy Savings
In fact, one air curtain manufacturer did a case study on a door opening for a typical heating season in Western Pennsylvania. The outside temperature was 36.5 degrees Fahrenheit and the inside temperature was 67.6 degrees. A ground-level, 12-feet-wide by 14-feet-high door was opened for two minutes without the air curtain operating, and the temperature dropped to 42.2 degrees – and that temperature was measured as far back as about 30 feet inside the building! In that same application with a non-heated air curtain operating, the temperature dropped less than 1degree. Imagine what an impact that makes on employee comfort as well as energy savings!
A similar case study was done during the cooling season. An overhead door was left open for three hours when the outside temperature was 94.9 degrees. Without the air curtain running, the indoor temperature was measured at 86.6. Under the same conditions with the air curtain operating, the inside temperature was measured at 74.4 — a much more comfortable working environment, which in turn improves productivity. In addition to reducing the hot air from entering the building, the air curtains will provide protection against insects, dust and debris, creating a cleaner, healthier work area.
Loading Docks
Loading Docks are yet another great application for air curtains. These doors allow significant heat loss in the winter, cause cooling issues in the summer, are susceptible to insect-control problems and even safety issues caused by water on the dock leveler.
All of these issues can be improved with the use of an air curtain. Most dock doors today have either dock seals or dock shelters to reduce the outside elements from entering the building during the loading operation. But anyone who has been around a loading dock in the winter knows that these measures reduce but don’t eliminate the infiltration. There are areas around the dock bumper and dock leveler lip as well as around the truck hinges that allow air infiltration into the building while the loading is in progress. Not to mention, that doors left open while a trailer is in the process of backing into the door opening, or delivery trucks that are too small for the dock seals to be effective negate the efforts of seals or shelters. And don’t forget that door openings that receive flat bed trailers can experience even bigger energy losses while the door is open. Air curtains are an ideal product to improve the safety and performance of a loading dock door in all of these situations.
Coolers and Freezers
Coolers are an excellent application for air curtains because they typically only have to overcome airflow due to temperature differential, not wind pressure. Air curtains are ideally suited for loading dock doors in cold storage applications. By reducing the warm air infiltration into the building during the loading/unloading process, the refrigeration equipment doesn’t have to work as hard to maintain temperature on the dock, thereby saving energy costs and increasing the life of the equipment.
Freezers can be a more challenging application. But when properly applied, an air curtain can reduce the warm air infiltration into the freezer when the door is open and minimize the frost build-up inside the freezer as well as on some types of cold-storage door panels when the door is closed. In addition, reducing the warm air infiltration can decrease the load on the refrigeration equipment — which in turn reduces the frequency of defrost cycles. All saving the customer money.
Less Maintenance
In almost any commercial application, by incorporating an air curtain into the door system the user can leave the door open during peak loading periods which will reduce door maintenance costs and repair costs due to accidental impact on the door. Also, air curtains may increase the life of your customer’s primary HVAC system by reducing the workload on the equipment.
Crunching the Numbers
So, what kind of ROI can you offer your customers? Many manufacturers offer an energy savings calculator on their Web sites. Let’s use the previous example from earlier in this article for using an air curtain during the heating season. The energy savings based on the door being open only one hour per day, five days a week was $2,423 over the course of the entire heating season. In this application the payback would be under two years, which is typical for an air curtain. So visit your customers and offer them a free energy audit. Educate them on all the benefits an air curtain can offer.
Michael J. Boyle is with M.J. Boyle LLC, a manufacturer's sales and marketing company that works with Powered Aire Inc., a leading manufacturer of industrial and commercial air curtains. More information is available by contacting Powered Aire at 888.321.2473 or visiting www.poweredaire.com.