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6-3
Automatic restarting or electrical shock can cause injury or death. Disconnect,
lockout and tagout package from the power supply.
AXIAL COOLING FANS
1. Follow Lock-Out Tag-Out procedures to de-energize the package. Allow adequate time for the
VFD capacitors to fully discharge before beginning maintenance.
2. Exercise caution around compressor parts after stopping the package for service. Fans and coolers
will be hot after stopping the compressor.
3. Remove access panels and guards as needed to gain access to the fan blades.
4. Cover motors, mixing valves, fan motors and other electrical components to prevent damage from the
cleaning process.
5. Use a mild detergent or degreaser to soften and dissolve accumulated grime.
6. Using a soft cloth or sponge, remove the surface grime from both sides of the blade surface.
7. Wipe up and remove all traces of cleaning residue and cleaning materials.
8. Reinstall all access panels and guards that were removed to access the fans.
9. Follow the Lock-Out Tag-Out procedures to re-energize the package.
10. Jog fans to verify there is no interference with the guard or cowling ring before the package is placed
back in service.
All axial cooling fans should be inspected and cleaned at the same interval as the heat exchangers are.
Ambient conditions will determine the actual maintenance interval at each installation
WATER COOLED HEAT EXCHANGERS
– Water Cooled heat exchangers (fixed shell-and-tube type)
are integral to the water cooled package. The air core is a single pass (air in the tubes) design and the oil
core is a double pass (oil in the shell) design. The cooling water is fed to the cores in a series
arrangement
– it passes through the air core first and proceeds through the oil core before exiting the
package. Please refer to Figure 6-2 for estimates of requirements.
AIR & OIL COOLER (Series Water Piping)
Water flow requirements at
various inlet water temperatures
(gpm)
Maximum
Water Flow
(gpm) *
Approximate (total) water
pressure drop @ 90
°
F
water flow
(psi)
KW
Model
60
°
F 70
°
F
80
°
F
90
°
F
260
VST225-260A
57.7
77.6
118.5
250.0
250.0
25.2
* Flows exceeding "Maximum Water Flow" will cause severe erosion and will void unit warranty.
Figure 6-2 – WATER CONTROL VALVE – WATER COOLED HEAT EXCHANGER COOLANT
REQUIREMENTS