How much does it cost when a chiller is down for an hour, a day, or longer? Build in chiller redundancy to virtually eliminate downtime. Redundancy can be achieved with an N+1 design, where N is the number of cooling circuits required for cooling the heat load and +1 is the redundancy. This type of redundancy will provide one extra refrigeration circuit that can be used to back up the other refrigeration circuits in the system. For instance, on a system requiring 20 tons of cooling, the standard chiller incorporates two refrigeration circuits of 10 tons each to provide the necessary cooling.
An N+1 design would use three circuits with each providing 10 tons of cooling. The first two circuits would provide the 20 tons of cooling required while the third provides the redundancy desired. The redundant circuit is rotated into the cooling process on a regular basis, equalizing compressor run time and ensuring the backup circuit is in working order when it is needed most.
Written by Dimplex Thermal Solutions, this article was originally published in Process Cooling magazine.