McDonalds: Campus Office Building

Left image: New units were carefully lowered into the building through a hatch in the loading dock. Right image: The new equipment provides a more stable and comfortable environment

Business Challenge

The existing heating and cooling in the building was supplied by two Hitachi direct fire absorbers. The 1,000-ton capacity of the machines was unequal, thus placing seventy-five percent of the load on one machine and only twenty-five percent on the other. This forced the larger machine into use the majority of the time, and did not allow for shut down to perform any extensive preventive maintenance. Because of reliability concerns and comfort issues, an equipment change had to be made.

The Air Comfort Solution

Air Comfort worked in conjunction with McDonalds chief engineer, Ken Tarasiewicz to devise a plan. The solution involved the installation of two low-pressure centrifugal chillers and two hot water boilers that equally split the design load and provide more stable heating and cooling to the building.

In order to prevent discomfort to the building’s employees, the new units were lowered into the central plant through a hatch in the loading dock before the old equipment was disconnected. Once the new chillers were brought online, the old equipment was removed. The replacement occurred without an interruption to the heating and cooling, and redundancy was maintained.

The Result

The new equipment provides more stable heating and cooling to the building. McDonalds benefits from energy savings based on the efficiencies of the boilers and chillers, and reduced maintenance costs because of the less complex equipment. Most importantly, the life span of the new equipment can be extended because extensive preventive maintenance can be performed. According to Ken, "The installation and performance of the new central plant has exceeded our expectations. What impresses me most is what others say about the job. Visitors to our plant say that it looks like it's always been there and when the building occupants found out the systems were replaced during the early summer they couldn’t believe there were no interruptions or disturbances."