Proper maintenance and cleaning of chiller systems after shutdown can help avoid future headaches during cold winter months. “Our experience is that being proactive and taking a look at the chiller system in the early winter leads to better results in the spring when it’s time to start the system up again,” says Tim Kane, president and CEO of Goodway Technologies, Stamford, Conn. “Performing chiller maintenance [early] in the winter gives facility managers the benefit of finding major damage with plenty of time to fix the problems before the chiller needs to be back in operation.”
The U.S. Department of Energy recommends that certain chiller maintenance operations be done at least once a year, including both cleaning and Eddy testing of condenser and evaporator tubes. Deferring maintenance can lead to further costs associated with additional repair and lost production time.
Many facilities do just that. According to a survey conducted by Goodway, nearly 89 percent of the survey respondents perform chiller maintenance at their facility once a year, and 64 percent said they typically perform maintenance between January and March. In addition, more than half conduct Eddy current testing during the same period, with 57 percent checking the tubes for flaws after cleaning the chiller.
What steps can you take to improve your chiller maintenance? Developing a plan or checklist for chiller maintenance can be beneficial, says the team at Goodway. Also, the checklist helps those tasked with preventive maintenance to stay on track while keeping equipment running properly and efficiently. Based on its experience, the company offered a five-step approach:
- Step 1: Maintain a Daily Operating Log. The Federal Energy Management Program (FEMP) recommends updating the log four times a day to monitor key operating parameters that will help indicate if any problems are developing.
- Step 2: Keep Tubes Clean. Fouling and scale can reduce efficiency. Regular monitoring can help recognize when tube cleaning should take place; however, it is recommended at least once a year. Pressure loss also can indicate tube corrosion.
- Step 3: Ensure a Leak-free Unit. Leaks can affect the operation of the system and release hazardous refrigerants.
- Step 4: Sustain Proper Water Treatment. Failure to perform chiller maintenance also can affect water quality. Keep a close eye on water treatment and chemistry.
- Step 5: Analyze Oil and Refrigerant. Refrigerant levels should stay within the manufacturer’s recommended levels. Using an air-purge timer (increases in air-purge time may indicate a leak), checking the refrigerant sight glass for bubbles and checking at all joints and connections with a gas analyzer are all ways to help track refrigerant levels.
“Chiller systems are one of the more complex pieces of equipment in a plant or facility, and it’s worth making the investment to take care of it,” Kane says.
Because chillers are one of the largest operational expenses in a facility’s process cooling or HVAC system, measuring efficiency gains can show facility managers important information, including costs saved as a result of regular maintenance. A proper operating log can also help identify areas that show improvement following chiller maintenance.
Visit www.goodway.com for additional education and to find facility maintenance tools from the company.