gForce Ultra IOM
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Brazed-Plate Fin Condensers
Data Aire water cooled units use brazed-plate condensers as a standard. Brazed-plate condensers are
constructed of plates brazed together to form an assembly of separate channels. Refrigerant is confined
to the space between the welded plates and is exposed to gaskets only at the ports. Such condensers
have a higher range of capacity.
The stainless-steel plates are configured with a wave pattern, which results in high turbulence and low
susceptibility to fouling. Because of the compact design, these condensers require a low refrigerant
charge. The construction of brazed units does not allow mechanical cleaning, and internal leaks usually
cannot be repaired. Thus, it is recommended to use closed-loop cooling systems with good filtration or
separators to keep the water clean.
NOTICE: Data Aire does not have experience of in-depth knowledge in the
field of water treatment and therefore only provides the following information
as a general reference. To properly maintain your water system, please
consult a water treatment expert.
Water Treatment
If impurities are not controlled, they can cause sludge or biological fouling. Simple blowdown
(discharging a small portion of the recirculating water to a drain) may be adequate to control scale and
corrosion on sites with good quality makeup water, but it does not control biological contaminants such
as Legionella. Chapter 49 of the ASHRAE Handbook—HVAC Applications covers water treatment in
more detail. Specific recommendations on water treatment can be obtained from water treatment
suppliers.
Scale Treatment
In daily use, scale accumulates at the water side of heat exchangers therefore regular scale treatment
is a must. Variations in water quality from place to place and variations in applications of plate heat
exchangers make it difficult to define in simple terms the water quality requirements for minimum
maintenance. It is important to ensure the right water quality and reduce scale by establishing the
requirements for local conditions or utilizing specialist water treatment companies.
The following should be paid attention to in daily maintenance.
Undissolved Solids (turbid water)
If undissolved solids and other fibers are in the water, the channels of the condenser are easily blocked.
Fibrous debris cannot pass the heat exchanger and must be disposed of. To reduce undissolved solids
blocking the condenser, granules should be kept smaller than 0.8 mm and is recommended to fit a 40
to 70 mesh strainer. Regular maintenance of this unit is required to ensure continued performance.
Dissolved Products
Under certain circumstance crystallized deposits of calcium and magnesium ion in the water will attach
to the condenser surface and scale. The higher the concentration of Ca2+ and Mg+ and the water
temperature, the greater the possibility of scale formation. Thick scale will not only gravely affect heat
transfer capability but even block the channels. As a result, never use this kind of water directly and
always carry out water treatment beforehand.
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