Hospital cures HVAC system

From his office window in North Carolina, Coy Overton can see the Atlantic Ocean. For most office dwellers such a view would be a major perk, but as plant operations director for Dosher Memorial Hospital, Southport, N.C., Overton sees moist, salty air—his worst enemy.

By Consulting Specifying Engineer Staff April 1, 2008

From his office window in North Carolina, Coy Overton can see the Atlantic Ocean. For most office dwellers such a view would be a major perk, but as plant operations director for Dosher Memorial Hospital, Southport, N.C., Overton sees moist, salty air—his worst enemy.

The saline atmosphere that surrounds the 100-bed community hospital wreaks havoc on galvanized metal cooling towers—towers that are essential to the operation of the facility’s HVAC system.

The corrosive nature of salty air decimated the hospital’s metal towers, causing leakage, disrupting service, and putting unusual demands on maintenance staff.

The solution was to replace traditional metal towers with a non-corrosive polyethylene product. When the first two 150-ton towers were installed in the late 1980s, Overton was a hospital employee but not the plant director.

By 1999 Overton had become plant operations director and knew what to do when Dosher began building a skilled nursing center, which would add more beds: He requested the installation of a third 150-ton plastic cooling tower. Were ceramic or stainless steel towers also an option? Sure, but the prohibitive cost made them unacceptable.

And when planning for an expansion of the hospital that began in 2003, everyone involved knew that the HVAC system would need to be expanded. Again, it was Overton who insisted on the use of plastic towers—specifically, towers developed by Delta Cooling Towers, Rockaway, N.J.

For Overton, who supervises a staff of six, patient care during emergency shutdowns of the HVAC system is the primary concern, but it’s not the only one. Dosher Memorial Hospital’s new addition houses an expanded emergency medical department and ancillary services, such as diagnostic imaging. To run properly, technology requires a controlled, comfortable environment every bit as much as people, Overton said.

“The equipment gives it up at certain temperatures. I think the CAT scans and MRIs start panicking at about 80 F. They’ll go down as the temperature rises,” he said.

The financial savings enjoyed by Dosher through the years has been considerable. But what price do you put on peace of mind? Because running a hospital leaves very little room for error, Overton convinced hospital administrators to fund the installation of a redundant cooling tower. Should one tower malfunction, the extra tower is ready to go so that there should be no disruptions of service. Overton said he keeps all towers functioning properly by rotating them each month, always leaving one as a standby.

“You’re dead in the water if you lose your system. We just can’t have that,” Overton said, adding, by avoiding emergency repairs his staff has been spared unnecessary overtime and scheduling nightmares.

Although the proximity of the Atlantic Ocean played into the hospital’s decision to use Delta, the real issue is pH levels. High or low (alkaline or acidic), a pH imbalance can trigger a destructive trend that causes metal-clad cooling towers to fail early or require extensive service.

Delta cooling towers are engineered with plastics such as high-density polyethylene so that they remain impervious to harsh chemicals, bitter environments, and pH deviations. As a result they have replaced the need for metal towers in much the same way that plastics have rewritten the standards in the plumbing industry. Also, the manufacturer claims that plastic towers are easier to install because they weigh 40% less than their metal counterparts, yet they are 5 to 10 times thicker.

Overton says that some maintenance of the Delta cooling towers has been necessary over the years. “We’ve had to do some rebuilding on them, but you would have had to do that anyway,” he said.

Information provided by Delta Cooling Towers, Rockaway, N.J.

AT A GLANCE

Dosher Memorial Hospital, Southport, N.C., needed a cooling tower solution that works with the hospital’s geography—near the Atlantic Ocean and its salty air.

Enter Delta Cooling Towers, Rockaway, N.J. The manufacturer’s plastic towers are ideal for the hospital because they are non-corrosive.

The Delta plastic cooling tower offers a 15-yr warranty on its shell. The single-piece construction on the basin means no leaks, which is an advantage over the sheet metal lined towers.

In addition, the cost of electric power to drive cooling tower fans can add up. For reduced maintenance, Delta Cooling Towers has designed its towers to use direct-drive motors to power fans.