In a head-to-head comparison, our customer selected the Eldridge Direct Drive Filtered Air Fan over options from a large, national competitor. We were able to recommend a solution that provided the customer with the required air flow performance at an overall better financial value. It was a great win for our customer and Eldridge Fan!
Application Design
Our customer, who operates a water bottling facility, was using exhaust fans with filtered louvers for air supply in their main filling room. The customer came to us wanting to provide a cleaner environment for the bottling operations by adding enough filtered supply fans to create a positive pressure in the room. The benefit of positive pressure in the main filling would be to prevent any infiltration of unfiltered air.
We worked with the customer to determine the airflow from their current exhaust fans. To provide sufficient positive pressure, we determined that the required amount of supply air would need to exceed the exhaust air by 10%. We wanted to produce enough positive pressure to prevent infiltration, but not so much that it would create safety problems when opening and closing man doors.
When using filtered air fans for filtered air supply, there are two constraints coupled with air velocity to consider in the selection process. First, air velocity at the opening of the weather hood. If the air velocity exceeds 1,000 feet per minute, rain would be drawn into the facility through the fan. The second constraint
is the air velocity at the filter face. The square footage of filter area would need to be large enough to keep the filter face velocity below 500 feet per minute. Anything above this would create additional static pressure.
Value Solution
Following our evaluation of the customer facility and airflow calculations, we determined that 14 Eldridge Direct Drive Filtered Air Fans would be needed. To provide the total required filtered supply air flow, the fans would need to be combined with weather hoods, mounting boxes, filter housings and gravity dampers. Eldridge Fans use an efficient cast aluminum airfoil propeller with adjustable pitch blades that can be set to provide the exact amount of airflow required. In this application, each of the 14 Eldridge Fans would only require a 2 hp motor.
Our competition proposed using fans with pressed aluminum fabricated propellers to provide competitive initial prices of the equipment. However, due to the inefficiency the propeller, their fans required 5 hp motors to provide the same amount of air flow per fan. Although their initial price had a small advantage over Eldridge Fan, this did not outweigh the financial disadvantage of years of excessive operating costs due to the additional horsepower needed by each of their fans.
Success
Once our customer reviewed the airflow solution provided and the long-term financial benefits of purchasing Eldridge Fans, the value added benefit was clear. It was proof positive that the customer recognized the financial value that Eldridge Fans would provide over the long-term when we received a purchase order. At Eldridge, we strive to provide optimal solutions for our customers. The Eldridge Fan line of products allows us to provide optimal long-term financial value solutions.