Another consideration for water is the required set point. Temperatures near or below 0°C (32°F) indicate that the chilled water plant condenser is very close to or below the freezing point of the water. (The minimum chilled water temperature to be supplied to the MCS 5042 is 7°C or 45°F.) This temperature might cause a blockage and damage to the unit, so an additive like glycol might be necessary to lower the freezing point. However the heat transfer potential of the water is lower, therefore, you must consider proper equipment capacity derating.
In a cooling loop, metallic materials in a pipe distribution network are in constant contact with re- circulating liquid and can react with impurities to cause corrosion that can develop into leaks or form deposits that can develop into blockages.
The rate of galvanic corrosion depends on the electrical potential between the two dissimilar metals and the temperature of the liquid.
Note:
A 10°C (50°F) rise in water temperature can double the rate of corrosion.
Additional water precautions
The following actions must be taken during the installation of the MCS 5042:
•Ensure that all foreign matter and particulates are flushed from the system prior to installing the water kit for the MCS 5042.
•Evaluate the short- and
•Ensure your chilled water loop is properly designed for liquid cooling systems, separate from the sanitary water systems within your building (such as, bathroom, sink, or drinking water).
•Make sure facility managers are aware of the additional load being added to the building chilled water supply. Be aware that the heat load being added might have an effect on other components being cooled by the chilled water plant.
Caution:
The water supply system feeding the MCS 5042 must be capable of withstanding deadheading (operating with a closed line) and operation with rapid and frequent changes in flow requirements, including long periods of time with zero water flow.
Plumbing materials to avoid
The following materials must not be used with a closed water system:
•Oxidizing biocides
•Aluminum components
•High zinc/brass components
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