East Campus Existing Building Conditions Heating and Cooling
The campus peak air conditioning load is presently handled by two 1,000 ton water cooled centrifugal chillers with chilled water pumps (2,000 gpm chilled water each) and a chilled water thermal energy storage tank with a chilled water pump (2,000 gpm) rated for 6,000 ton/hours of capacity based on 42 degrees F. leaving water and 54-degree returning water, a 12 degree temperature rise. This allows the central plant to meet a peak cooling demand of 3,000 tons or 6,000 gpm of chilled water flow for a maximum period of six hours. The chilled water thermal energy storage tank must be re-charged with cold water at night for the next day’s use.
The majority of the underground chilled water utility piping has been upgraded in size and/or material. Most of the campus buildings have secondary chilled water pumps with variable frequency motor speed controllers and two-way modulating temperature control valves.
The heating water system consists of two 12,600,000 BTUH input (300 boiler horsepower) forced draft fire tube boilers each with a hot water pump. The campus hot water utility distribution piping delivers 120 to 180 degrees F. hot water to the buildings based on a hot water reset schedule inversely with outdoor temperature. Some buildings utilize a reheat process to maintain space temperature and humidity control.
An industrial grade heat pump chiller produces low temperature hot water for heat and reheat requirements. The system is tied into the existing condenser water piping and existing hot water piping. A rate reduction rider for generating the low temperature hot water from Central Power & Light Company requires this system to be operable and in use to reduce the use of natural gas.
The majority of the underground hot water utility piping has not been upgraded in size and/or material. Most of the campus buildings have two-way and three-way modulating control valves for temperature control.