HVAC Case Study
A Healthcare Facility Installation
Dallas Methodist Hospital Case Study – Cooling System Transplant
Refrigeration and Environmental Systems converted this healthcare facility’s cooling system to an all variable speed format. Using Armstrong chilled water and condenser water pumps, a new chiller and cooling tower, the outcome was a success. The Armstrong pumps were controlled by an Integrated Plant Controller (IPC) 11550.
Summary of Outcome
After a retrofit installation of updated HVAC equipment, Methodist Dallas Medical Center reduced their cooling costs over $300,000 over a year. The new system not only saves energy, but also creates a more comfortable environment for staff and patients. The hospital now experiences sharp reductions in “hot” calls. The maintenance staff says that the new system is far easier to operate, monitor, and adjust.
Since 1927 the Methodist Dallas Medical Center serves North Texas. The hospital includes a Level III Neonatal Intensive Care Unit. Methodist Dallas Medical Center is home to the Methodist Dallas Transplant Institute, one of the largest, most active multi-organ transplant centers in the southwest United States.
The facility recently underwent a transformation as a result of a retrofit HVAC project. When the retrofit project was first proposed, the legacy mechanical system included a 30-year-old cooling tower and a 25-year-old chiller. The original solution included some piping irregularities that led to inefficient operations.
Refrigeration and Environmental Systems proposed a new design to the hospital’s facility managers. The facility managers were interested in the proposed energy savings. They were concerned about the upfront costs of the equipment and skeptical that any new technology could provide the proposed improvements.
This was the customer’s first exposure to variable speed technology. To address their concerns, Armstrong provided a written commitment regarding the performance of the system. With that assurance in hand, the hospital agreed to the proposed system.
The facility managers had not previously worked with Vertical In-Line pumps, but on the recommendation from Refrigeration and Environmental Systems they agreed to designing the system around the Armstrong VIL. Tim Rusher of RushCo explained how he had supported the use of Armstrong pumps in discussions with hospital officials. “I told them that Armstrong makes the best chilled water pumps in the world. I’ve used them for years. For HVAC installations, we prefer them over any other brand of pumps.”
The retrofit project involved several weeks of work on-site. The old equipment was removed and preparations made to accept the new equipment. The retrofit included cutting a hole to install the new chiller. The final system included a new cooling tower, a new chiller, improved piping coupled with key components provided by Armstrong:
3 X 250 hp VIL pumps to serve the chilled water system
5 X 100 hp VIL pumps to serve a condenser water system
Integrated Plant Controller (IPC) 11550
Armstrong makes the best chilled water pumps in the world. I’ve used them for years. For HVAC installations, we prefer them over any other brand.Tim Rusher
Frequently Asked Questions
About the Armstrong IPC 11550 System with Ultra-Efficient Chilled Water Plant Control Utilizing Hartman LOOP™ Technology
The IPC 11550 is an automated purpose duty control system designed specifically for energy efficient control of chilled water plants for comfort cooling (HVAC applications). The IPC 11550 manages the sequencing, operation, positioning, and/or speed control of the following chilled water plant devices:
• Chiller isolation valves
• Variable primary flow by-pass modulating valve(s)
• Building VPF pumps
• Condenser water pumps
• Cooling tower fans
• Chilled water supply temperature reset
• Emergency shut down and general recovery sequences
The IPC 11550 includes Hartman LOOP™ control methodology for ultra-efficient all variable chilled water plant control.