10
Water Cooled Package Air Conditioner
Introduction
Maintenance
- Preventive Maintenance
Maintenance on the unit is simplified with the following preventive suggestions: Filter
maintenance must be performed to assure proper operation of the equipment. Filters should be
inspected at least every three months, and replaced when it is evident they are dirty.
Check the contactors and relays within the control panel at least once a year. It is good practice
to check the tightness of the various wiring connections within the control panel. A strainer (60
mesh or greater) must be used on an open loop system to keep debris from entering the unit
heat exchanger and to ensure a clean system. For units on well water, it is important to check
the cleanliness of the water-to-refrigerant heat exchanger. Should it become contaminated with
dirt and scaling as a result of bad water, the heat exchanger will have to be back flushed and
cleaned with a chemical that will remove the scale. This service should be performed by an
experienced service person.
- Hazardous Chemicals
Coil cleaning agents can be either acidic or highly alkaline. Handle chemical carefully. Proper
handling should include goggles or face shield, chemical resistant gloves, boots, apron or suit as
required. For personal safety, refer to the cleaning agent manufacturers Materials Safety Data
Sheet and follow all recommended safe handling practices. Failure to follow all safety
instructions could result in death or serious injury. It should be noted that the water quality
should be checked periodically. See the following water quality table.
Scaling
Calcium and magnesium(total hardness)
Less than 350 ppm
pH
7 ~ 9.5
Hydrogen Sulfide
Less than 1 ppm
Corrosion
Sulfates
Less than 25 ppm
Chlorides
Less than 125 ppm
Carbon Dioxide
Less than 75 ppm
Total dissolved solids(TDS)
Less than 1000 ppm
Biological Growth
Iron Bacteria
Low
Erosion
Suspended Solids
Low
