The third time was the charm for these facilities.  The 600 Corporate Point facility was originally designed and installed with a low temperature air and ice storage (ice harvester) combination.  Water at 34°F was supposed to be available to be pumped through very undersized cooling coils to cool the air to 50°F to provide cooling to the tenants.  After this system failed, the previous owner performed a retrofit that eliminated the ice storage, added chillers designed for 35°F chilled water production, and converted the ice storage tanks to an “empty-tank” chilled water storage system.

This second system proved incapable of meeting the needs of the tenants, with a substantial number of controls and mechanical failures that mandated an engineer be on site whenever a tenant was in the facility.  This would not normally be a problem, but the major tenants in this facility operate from 6:00 AM to Midnight Monday through Friday, 8:00 AM through Midnight Saturday, and 8:00 AM  through 6:00 PM Sunday.  The operating expenses were killing the facility, as they could not be completely recovered from the tenants due to the lease agreements made by the previous owner.

In an attempt to meet the cooling requirements of the tenants, both chillers, plus the TES system had  to be run whenever the ambient conditions were over approximately 73°F, or if it were humid outside.  The fan systems were providing 58°F to 64°F supply air to the spaces, the face velocity across the cooling coils was in excess of 600 FPM, and the condensate was being carried off the coils horizontally into the fans.  Thus, even with both chillers and the TES system operational and serving only one building, the tenants needs were not being met.

The building next door, 400 Corporate Point, was equipped with water cooled floor by floor self contained Direct Expansion compressorized systems, operating in excess of 1.0 kW per ton delivered.  The fan systems were undersized, the cooling tower was undersized and in need of replacement and the compressors and condensers were beginning to fail on a regular basis.

ROI teamed up with Control Air Conditioning Service Corporation to compete for this project.  Once again, the ROI solution was deemed to be the most viable and financially strongest option evaluated by the owners in-house engineering and operations team.

Our team replaced  the cooling coils in both buildings (chilled water and DX) with new chilled water cooling coils capable of providing a 32°F to 34°F (measured during the summer) chilled water temperature differential.  The TES system was converted to a stratified chilled water design, with headers designed by ROI, and a new Siemens DDC system was added to control the new equipment, as well as the air handling equipment in both buildings.

There was no new refrigeration equipment added to the buildings, and over 500 tons of DX compressor capacity was removed from 400 Corporate Point.

By carefully engineering the solution, our Team was able to convert a chiller plant/TES system that was undersized for one building, into a system that has proven capable of meeting the needs of two buildings.

After accounting for energy efficiency incentives, this project should deliver a simple payback of three to four years.

Challenger Memorial Youth Center | 400/600 Corporate Point
Jamboree Center | McArther Court