125 PSI Steam is supplied to campus buildings 24 hour a day 7 days a week. The steam is used in campus buildings for heating air, hot water, humidification, reheating of cooled air, cooking and other small processes. The steam is distributed to campus buildings through a series of underground tunnels and miles of pipe. At the buildings the steam pressure is reduced then it is used to heat domestic and building hot water, in HVAC steam coils or for radiator heating.
Steam Pressure Drops
Power interruptions even small ones have the ability to shut down plant equipment. This is because boilers, chillers and large motors in the plant use electro magnetic devices to hold in the starter contacts that are needed to power equipment. There are several reasons equipment is operated this way but mostly it is to protect the equipment and personnel against unsafe running conditions. Any loss of power causes the electromagnetism to fail resulting in equipment shutdown. A power interruption even one as small as a flash of plant lighting can shutdown some or all of our equipment disrupting steam, chilled water and compressed air to campus. All most all plant steam pressure reductions are cause by power interruptions or bumps originating with the incoming power source. Plant operators are trained to swiftly bring plant equipment and the plant back on line to minimize the effects to campus buildings.
Each year the week before Memorial Day the steam is shut down to campus for 4 and ½ days to allow Facilities services to make repairs to the central steam system on campus. There are many systems including the Central Heat Plant and the utility tunnel that operate 24/7 throughout the year that can not be worked on while in operation. Failure to make these scheduled repairs would cause unscheduled steam shut downs during the course of the year. This could cause freeze damage to buildings, disruption of classes and ruin ongoing research projects. Steam is normally shut down on Sunday at 8:00 PM and restarted Friday morning at 7:30 AM. If all goes well, steam will be back up to pressure in campus buildings by 12:00 PM and the chillers back on by 1:00 PM.. Cooling is also shut down during this time because there is no steam to operate the steam turbine chillers at the plant and the electric driven chiller can only be operated during off peak hours in the month of May. Running this chiller on peak will generate an additional demand charge of $19,000 in addition to the KWH usage charges for operating the chiller during the month. On the Wednesday of shutdown the Central Plant sponsors a picnic lunch, afterwards a group photo is taken of plant staff and their guests.
A few of the projects being performed for 2009 in the utility tunnels include: Re-piping and installation of steam and condensate isolation valves for the Student Union, Installation of steam expansion joint retainers at Sandburg take off, replacement of the steam ball joint at the Cunningham building, the replacement of the 6 inch steam supply valve to the Klotsche building.