8
• Lubricate the fan shaft bearings. At initial
start-up, no bearing lubrication is required
unless the unit has been idle for more than
three months. Refer to
page 17
for
more details.
• Apply a good quality, corrosion inhibiting
grease, such as one of those recommended
for lubricating the fan shaft bearings, to the
adjustable motor base and threaded rod.
See
Figure 3
.
• Apply RUST VETO
®
to steel shafts and bushings.
• Check the belt tension, and adjust if necessary. See
page 14
for more details.
• Set the make-up valve float so the water shuts off at the operating level. See
Table 2 on
page 12.
• Start the unit pump and check for the proper rotation indicated by the arrow on
the pump cover. Perform one of the following biocide treatment programs while
operating only the pump. Do not operate fans until after the biocide treatment has
been completed, and the biocide or chlorine levels have been reduced to normal
operational levels.
– If this is a startup after the tower has already operated with biocide treatment, then
resume treatment with the biocide that was used prior to shutdown. Operate only the
pump 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.
– 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 Cl
2
) over a six hour period. Test kits for
measuring the free residual of chlorine are commercially available.
• After the biocide treatment period is completed, bring the biocide and/or chlorine levels
to normal operational levels.
• Resume operation with the standard water treatment program (including biocidal
treatment) as recommended by the water treatment supplier.
• Check that the float operated make-up valve is operating freely. Closely monitor water
level and adjust as necessary during the first 24 hours of operation. Refer to
Table 2
for
more details.
• Inspect the heat transfer section as described on
page 18
and inspect the water
distribution system as described on
.
• Passivation is required for galvanized coils. See
page 24
for more details.
• On initial start-up, or if the fan motor has been rewired, briefly energize the fan motors
and note the direction of rotation. Fans should rotate in the direction indicated by the
arrow on the fan cowl.
• Run the fan in the manual position for several minutes and check for any unusual noises
or vibration. Correct as necessary.
• Test the vibration cutout switch (VCOS). See
page 34
for more details.
• While the unit is operating at full speed under heat load and during near design ambient
conditions, check the current and voltage of all three phases (legs) of the fan motor. The
current should not exceed the nameplate full load amp (FLA) value.
• To identify resonances within the operating speed range, see
page 37
.
• For units with the optional Electric Water Level Control, see
page 20.
Figure 3.
Adjustable Motor Base
NOTICE:
Ensure the controls for
the fan and pump motors are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overheating.
After 24 hours of operation
under thermal load, perform the
following services:
9
Check the unit for any unusual
noises or vibrations.
9
Check the operating water
level in the cold water basins.
Adjust the make-up valve if
necessary. Thereafter, closely
monitor the cold water basin
operating level when the tower
is under thermal load near
design conditions, and adjust
as necessary to maintain an
operating level of 8 1/4”.
9
Check the belt tension and
readjust if necessary.
9
Re-inspect the spray nozzles
and visible heat transfer
section.
