Children's Medical Center - Central Plant Renovation

The original central plant at Children’s Medical Center consisted of five centrifugal chillers with a total capacity of 3,000 tons of cooling, and two 400 BHP high pressure steam boilers. This equipment was located in a building remote to the main facility, with four cross-flow induced draft cooling towers located on the roof. Steam and chilled water was distributed to the existing Tower I and Tower II through two utility tunnels; a north tunnel and a south tunnel. Existing 480V diesel fueled emergency generators were located at various points on the site. 

As part of Tower IIIA construction, we designed a new central chiller and emergency generator plant to serve the facility. We located six 1100 ton centrifugal chillers in the basement of the new Tower IIIA, with six corresponding induced draft cross-flow cooling towers on the roof. Chilled water pumps for a primary-secondary chilled water distribution piping system were located in the basement, as well as condenser water pumps for the cooling towers. New primary loop chilled water piping was routed to the existing piping from the existing central plant. The flow through the south loop was reversed, and tied to the north loop at the existing central plant. In this way, the new chiller plant was able to serve the old West and East towers of the hospital as well as the new Tower IIIA.

After the new chiller plant was operational and tied to the existing towers, the old chillers and cooling towers were demolished. Two new 500 BHP high pressure steam boilers and a new deaerator were installed in the space vacated by the old chillers. The new boilers were tied to the existing steam header. The existing distribution piping in the north and south tunnels was large enough to accommodate the loads for the new Tower IIIA.

Four new 1500 KW diesel fueled emergency generators and associated switchgear and transfer switches were installed in the Tower IIIA basement. The new generators provide 4160V, 3PH power which is distributed to various electrical rooms in Towers I and II, then transform down to 480V, 3PH. After the new generators were operational, the existing distributed generators were demolished.

When Tower IIIB was constructed, the IIIA central plant was expanded to include two new 550 ton centrifugal chillers as well as an additional cooling tower cell on the roof of Tower IIIA, and all associated pumps and piping necessary to tie into the existing chilled water system. Secondary chilled water piping was distributed to Tower IIIB to serve the new tower.