Behind the Scenes: The cold, hard facts about CSULB’s air-conditioning

Across the stairs from the University Student Union, steam rises from towers atop a building called the central plant.

Few know that beneath those towers lie waterfalls that are used to remove heat from water that will be dispersed throughout campus in an intricate system of pipes that serve as air-conditioning.

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Long Beach State’s air-conditioning system has been in service since 1997. The complex machines inside the two buildings whir loudly as they work together to complete a cycle that has been perfected over the years.

“We have a state of the art, highly sustainable central plant that has won many awards and has been emulated as the goal for best practices for many years to other universities,” said Mark Zakhour director of design and construction services.

Up a flight of stairs is where the process begins with five ice harvesters that create ice from water treated with a chemical biocide to prevent algae, and a chemical inhibitor to prevent adverse chemical reactions. 

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These harvesters run all night from 10 p.m. to 8 a.m. to avoid hot temperatures and produce 250 pounds of ice an hour.

Below them lies a 27-foot deep pit that holds 180,000 gallons of water and ice which is enough to cool 1,000 homes for eight hours during the summer. The water then goes to chillers to remove heat from the water.

“Chillers are very common in large areas, especially in places with lots of rooms,” said Chris Stiner the owner of Perfect Air-Heating and Air-Conditioning.

Stiner said that most air-conditioning units are run solely off of refrigerant that helps transitions liquids into gas. The smaller units absorb the heat that passes through them, and according to Stiner, that is why most air conditioning units are hot to touch despite cooling the air.

Ice powered systems aren’t familiar to Stiner, and he said that he hasn’t worked on chillers in a long time. Christian Tsouras, facilities control specialist, said that the way the CSULB runs the air-conditioning is becoming less common.

“Very few campuses do it as comprehensive as this,” Tsouras said. “It’s surprising that people haven’t done this in the past.”

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Tsouras described the cycle of the water to be very similar to veins and arteries. The water goes below to get just above freezing and then travels out to the school. It returns as warm water, only to be cooled again and start the process all over.

“[The central plant] is really the heart of the operation,” Tsouras said.

After the water is cooled it travels across the courtyard to the waterfalls where the heat gets rejected from the system. From there, it falls into a three-foot pool that is cleaned monthly. The water then flows into another pit, this one 15 feet deep, to go out to the school in six-inch-wide pipes.

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The water that is cycled around CSULB is reused over and over again with very little loss, according to Kevin Hottle the air-conditioning refrigeration mechanic. 

With that much water, there is cause for concern regarding sustainability, but Shawn Cun, the energy and utilities manager, said that the department always keeps conservation in mind.

A consultant will be visiting the central plant soon to evaluate it and make sure that the system in place is still the most efficient way to cool the campus. Cun also said that facilities is looking into getting a heat-recovering chiller to reduce gas consumption by 75%.

“We’re always looking for the most energy-efficient method to operate the plant,” Cun said.