During a recent commissioning study conducted on a cooling tower, Barton Associates found a manufacturing defect in the system’s factory panel wiring that could have caused the owner significant problems. The PLC output wiring for the high speed and low speed fan drives had been inadvertently switched by the manufacturer. This mistake would have caused the high speed fan to run instead of the low-speed fan on partial load days, resulting in unnecessary use of 10 additional horsepower.
On peak load days, the fan would have switched from high speed to low speed causing excessive operating temperature in the condenser water loop. This would have forced the owner to start up an additional chiller to maintain chilled water loop temperature or shed cooling load-an unnecessary action that could have cost the owner an additional $200 or more per day to run.
Barton was able to troubleshoot and resolve this problem in under an hour, but had it gone un-noticed, this mistake could have cost the owner hundreds, or even thousands, of dollars in wasted energy costs.
A general contractor or electrician would not typically identify a manufacturing defect of this nature; however, a commissioning study conducted by a certified professional could help save your system from potential problems like this.