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13-17-609 Page 59
6-4
The water supply shall be capable of delivering the flow/temperature combinations shown in
Figure 6-2 page 58, at a minimum pressure of 40 psig (2.8 bar) - the water flow rates shown are
approximate and a guide to sizing of piping, cooling tower and other water system equipment.
The maximum allowable supply water pressure is 150 psig (10.3 bar) and the maximum allowed
[package] outlet water temperature is 110
°
F (43
°
C). If a water supply with a temperature lower than 60
°
F
(16
°
C) is used, heat transfer areas of the coolers may be fouled due to low water flow velocities, resulting
in poor cooler performance and shortened operational life.
All the required hardware, mechanical and electrical connections have been made at the Gardner Denver
factory. Regular maintenance is required to keep the interior core areas free from dirt and other fowling
agents. In order to protect package components that are in contact with the cooling water from attack by
corrosive or fouling agents, we recommend that the cooling water meet the following quality standards
Total Dissolved Solids (TDS) ................... <500 ppm
Iron ......................................................... <2 ppm
Total Hardness ........................................ <60 ppm
Silica ....................................................... <25 ppm
Oil and Grease ........................................ <5 ppm
Sulfate..................................................... <50 ppm
Chloride .................................................. <50 ppm
Nitrate ..................................................... <2 ppm
Corrosivity ............................................... Langelier Index between 0 to1
It is strongly recommended that a reputable, local firm be contracted to evaluate the quality of water
available and recommend corrective and/or preventive steps to meet our requirements.
WATER FLOW REGULATING VALVE (OPTIONAL HARDWARE)
.
– This device is used to adjust the
flow of cooling water in proportion to its temperature. It
’s a normally closed (two-way) valve which opens
once the thermostatic bulb senses a predetermined water temperature level and then continues to
modulate water flow to maintain water temperature
– within a 2
°
F to 5
°
F span. The package piping
provides a permanent bypass line (1/4
” tube) around the flow regulating valve to ensure water flow
around the sensing bulb when the valve is in the closed position
– it does not provide a complete shutoff
of water flow.
Figure 6-2 – WATER CONTROL VALVE