140.960-IOM (JUN 2016)
Page 35
IDCF & IDC3 EVAPORATIVE CONDENSERS
OPERATION
OPERATION
INITIAL AND SEASONAL START-UP
General
• If the unit is mounted on vibration isolators or isolation rails,
refer to the vibration isolation manufacturer’s guidelines
before loading/unloading weight from the unit.
• Verify fan(s) and motors are disconnected, locked out and
tagged out.
• Conduct external inspection of the equipment. Check for
leaks, corrosion, and any structural damage.
• Inspect piping and connections.
Cleaning
• Drain the water basin with the strainers in place.
• Remove all dirt and debris from the fan guards and
combined inlet shields.
• Inspect and clean all spray nozzles.
• Clean all mechanical components, such as the fans and
motors.
• Flush the water basin interior to remove any accumulated
dirt and debris.
• Remove, clean, and replace the basin strainers.
Inspection
DANGER
Do not perform any service on or near the fans, motors,
drives, or inside the unit without first ensuring that the fans
and the pumps are disconnected and locked out. Rotating
equipment can cause severe personal injury or death to
persons who come in contact.
• Conduct thorough external inspection of the equipment.
Check for leaks, corrosion, and any structural damage.
• Conduct thorough internal inspection of the equipment.
Check for anything unusual such as structural or mechanical
component damage.
• Inspect piping and connections.
• Thoroughly inspect the fan(s) for any mechanical or
physical damage.
• At seasonal start-up or after prolonged shutdown, check
the motor insulation with an insulation tester prior to the
motor start-up.
• Check and adjust the belt tension. The 0406 and 0412
models use direct drive motors and do not require belt
tension.
Start-up
Initial Start-up Considerations:
• For units with independent fan control [standard on 0412
and 0718, and optional on 1218, 2418, and 2436], see "Fan
Control" section.
• For units with VFDs, see "Variable Frequency Drive" section.
• For units with vibration cutout switches, see "Vibration
Cutout Switch (VCOS)" section.
Procedures:
• Prior to seasonal start-up, lubricate the motor base
adjusting screw and the fan shaft bearings. At initial start-
up, no bearing lubrication is required since the bearings
are factory lubricated prior to shipment.
• Apply RUST VETO® to steel shafts.
• Fill the water basin with fresh water to the overflow level
via the make-up valve.
• Set the make-up valve float so the water shuts off at the
operating level (see Table 1).
• Execute one of the following biocide treatment programs
while operating the circulating pump and prior to operating
the unit fan(s):
• Resume treatment with the biocide that was used prior to
shutdown. Operate the pump only while maintaining the
maximum recommended biocide residual for a sufficient
duration (residual and time will vary with the biocide) as
recommended by the water treatment supplier. Start the
fan only after this treatment period is completed.
• Check the pH of the circulating water and, if necessary,
adjust it to 7.0 - 7.6 pH. Then, running the pump only,
treat the system with sodium hypochlorite to maintain a
level of 4 to 5 mg/l (ppm) free chlorine (as Cl2) over a
six hour period. Test kits for measuring the free residual
of chlorine are commercially available. Start the fan only
after this treatment period is completed.
• Start the unit pump and check for the proper rotation
indicated by the arrow on the pump cover.
• On installations where the unit pump is not furnished, a
globe valve should be installed in the pump discharge line
and the pump flow rate adjusted to the correct water flow
and pressure (2.25 psig at spray header connection).
NOTICE
Spray system pressure greater than 10.0 psig may cause
damage to the distribution system.
• Check that the float operated make-up valve is operating
freely. Closely monitor the water level and adjust as
necessary during the first 24 hours of operation.
• Inspect the nozzles and heat transfer section as described
in “Water Distribution and Heat Transfer Section."
• Verify proper fan tip clearance. Refer to Fan “Inspection &
Maintenance."
• Open the valve in the unit bleed line, and adjust the bleed
by closing or opening the valve until the desired bleed rate
is reached.
• For initial start-up, briefly energize the fan motor(s) and
note the direction of rotation. The fan should rotate in the
direction indicated by the arrow on the fan cowl.
NOTICE
Check to ensure the controls for the fan motor are set to
allow a maximum of six on-off cycles per hour to prevent
motor overload.
