Preventive Maintenance Frequency Factors
March 1, 2009
The preventive maintenance period for chillers depends on a number of factors, including:
- Number of hours of operation per day and the type of
- Environmental conditions and location of the chiller.
- Coolant used in the system.
Environmental conditions also play a role in the amount of maintenance a chiller will need. Chillers should only be used indoors at a maximum relative humidity of 80 percent. High humidity can result in condensation that could damage electrical components in the chiller or on the equipment it is cooling. Chillers also only should be operated at ambient temperatures between 55 and 95°F (13 and 35°C). Extreme temperatures can negatively impact thermal performance, cause strain on electrical components and result in freezing and bursting of the evaporator.
Chillers should be used in areas that are relatively clean and dust free. The dustier and dirtier the air, the more maintenance the chiller is likely to need. Using an air filter is recommended if the ambient air is dusty. However, it is important to note that an air filter will add slightly to pressure drop; therefore, it will cause a slight decrease in thermal performance.
The other factor that significantly impacts maintenance is the type of coolant used. If water is the chiller coolant, it is critical to use clean, filtered water. Water with high mineral content can lead to corrosion and fouling of coolant passages, resulting in system clogs or leaks. Many companies recommend using a corrosion inhibitor as well as an algae inhibitor to prevent growth in the reservoir.