Condenser Fans; High Static Fan Option; Refrigerant Circuit; Safety Devices - Carrier AquaForce B Series Controls, Start-Up, Operation, Service And Troubleshooting Instructions

9. Finned surfaces should remain wet with cleaning solution
for 10 minutes.
10. Ensure surfaces are not allowed to dry before rinsing. Reap-
ply cleaner as needed to ensure 10-minute saturation is
achieved.
11. Thoroughly rinse all surfaces with low velocity clean water
using downward rinsing motion of water spray nozzle. Pro-
tect fins from damage from the spray nozzle.

Condenser Fans

A formed metal mount bolted to the coil caps supports each fan
and motor assembly. A shroud and a wire grille provide protection
from the rotating fan. See Fig. 72. To remove the fan a special
puller (RCD part no. 30RB680082) can be used. The fan utilizes a
set screw and does not require the use of retaining compound in
the keyway. The fan can be removed without the puller, but its use
eases disassembly. The exposed end of the fan motor shaft is pro-
tected from weather by grease. If fan motor must be removed for
service or replacement, re-grease the fan shaft. The fan needs to be
positioned fully down against the step on the motor shaft. Apply
blue thread locker (Loctite 243) to the threads of both the axial
bolt and the set screw. Install the thick washer and M8 axial bolt;
do not fully tighten. Install set screw and tighten to 16 ± 2 ft-lbs
(21.7 ± 2.7 Nm). Torque the axial bolt to 24 ± 2 ft-lbs (32.5 ± 2.7
Nm). Reinstall shroud and wire grille.

High Static Fan Option

A different fan blade is used for the high static fan option. It
does not have the set screw to retain the key, so retaining com-
pound must be used. The same puller is required to remove this
fan blade. Use Loctite 603 retaining compound on the shaft
and keyway during re-assembly. Remove any grease or con-
taminates from the fan motor shaft before installation.

Refrigerant Circuit

LEAK TESTING
Units are shipped with complete operating charge of refriger-
ant R-134a (see Physical Data tables supplied in the 30XV in-
stallation instructions) and should be under sufficient pressure
to conduct a leak test. If there is no pressure in the system, in-
troduce enough nitrogen to search for the leak. Repair the leak
using good refrigeration practices. After leaks are repaired,
system must be evacuated and dehydrated.
REFRIGERANT CHARGE
Refer to Physical Data tables supplied in the 30XV installation in-
structions. Immediately ahead of filter drier in each circuit is a fac-
tory-installed liquid line service valve. Each valve has a
cess connection for charging liquid refrigerant.
1 / -in. ac-
4
FORMED METAL
MOUNT
FAN DECK
MOTOR
Fig. 72 — Fan Mounting
75
Charging with Unit Off and Evacuated
Close liquid line service valve before charging. Weigh in charge
shown on unit nameplate. Open liquid line service valve; start unit
and allow it to run several minutes fully loaded. Check for a clear
sight glass. Be sure clear condition is liquid and not vapor.
Charging with Unit Running
If charge is to be added while unit is operating, all condenser
fans and compressors must be operating. It may be necessary
to block condenser coils at low ambient temperatures to raise
condensing pressure to approximately 198 psig (1365 kPa) to
turn all condenser fans on. Do not totally block a coil to do this.
Partially block all coils in uniform pattern. Charge each circuit
until sight glass shows clear liquid, and has a liquid line tem-
perature of 103°F (39°C).
Add 3 to 5 lb (1.36 to 2.27 kg), depending on unit size and coil
type, of liquid charge into the fitting located on the tube enter-
ing the evaporator. This fitting is located between the electron-
ic EXV and the evaporator.
Allow the system to stabilize and then recheck the liquid tem-
perature. If needed, add additional liquid charge, 3 to 5 lb at a
time, allowing the system to stabilize between each charge ad-
dition. Slowly add charge as the sight glass begins to clear to
avoid overcharging.
IMPORTANT: When adjusting refrigerant charge, circulate
fluid through evaporator continuously to prevent freezing and
possible damage to the evaporator. Do not overcharge, and
never charge liquid into the low-pressure side of system.

Safety Devices

The 30XV chillers contain many safety devices and protection
logic built into the electronic control. Following is a descrip-
tion of the major safeties.
COMPRESSOR PROTECTION
Motor Overload
The compressor VFD fuses and drive logic protect each com-
pressor against overcurrent.
All compressors have factory-installed high-pressure switches.
See Table 46. Each high-pressure switch is connected directly
to its associated VFD (terminals 12 and 37). If the switch
opens during operation, the compressor will be shut down.
Manual reset of the high pressure switch, VFD, and the control
is required to restart the compressor.
Table 46 — High-Pressure Switch Settings
UNIT
psig
30XV 323.5 + 0.0 –14.0
WIRE GUARD
SWITCH SETTING
kPa
2230 + 0.0 –14.0
FAN BLADE
a30-5863