Facilities Management employs new process to improve chilling

May 1, 2013

Facilities Management has made strides to eliminate uncomfortably warm indoor temperatures, typical of this transitional time of year, by initiating chiller start-up early. With the early jump, chillers across campus are primed and on standby, ready to provide air conditioning to campus buildings.

Preparing the system three weeks ahead of the regular schedule is a direct result of being caught off guard by an unseasonable warm spring last year. Not having the chiller prepared lead to uncomfortably high indoor temperatures. It wasn't a scenerio the Division was looking to repeat. However, having the chillers online early comes with risks.

“There are reasons we haven’t started the chillers this early in the past,” says Gary Bridgens, Director, Facilities Management. “The process required precise coordination with the variable Spring temperatures, when extremes are capable of damaging the chilled water equipment.

Unlike at home, changing from heating to cooling requires much more planning and preparation than flipping a thermostat switch. With more than 90 buildings and millions of square feet of occupied space, the campus system can take more than three weeks to prime for start-up.

The majority of the preparation time is spent filling the coils that are emptied in the fall to prevent winter freezing. Although time consuming, it is a critical procedure. If outdoor temperatures dip below freezing the coils are subject to freezing, swelling, and splitting. As temperatures warm, the system thaws and leaks, rendering the equipment useless until repairs can be made.

“Keeping the delicate balance of comfortable indoor air temperatures and finding that sweet spot when we can safely start up the chillers has always been a challenge,” says Bridgens. “Current technology is allowing us to ease some of that timing pressure through the use of anti-freezing measures.”

With an automated pumping system, the coils can now be filled sooner. This year, fitters began filling coils three weeks earlier than in previous years. Should outdoor temperatures dip below five degrees Celsius, the system triggers the pumps to push water through the coils. Because moving water has a lower freezing point the pipes will remain open until the temperatures return to normal.

“There is still a risk of damage if the temperature sensing mechanisms or the pumps fail, however, we believe our customers will appreciate the enhancements we’ve made to have air conditioning ready earlier and that the potential benefits outweigh the risk involved,” says Bridgens.

Though these proactive measures will help to reduce temperature fluctuations in most buildings, it should be noted that irregular indoor temperatures are inevitable throughout the changing season. The campus community is encouraged to contact Facilities Management and report conditions that fall outside of acceptable standards for extended periods of time.

“We’d like to think that we will stop all irregularities by being ahead of the game,” says Bridgens. “That’s just not realistic, so we are still asking our customers to dress appropriately and expect brief periods of fluctuation.”