Carrier 30GTN, Руководство по обслуживанию и устранению неисправностей, Страница: 52 / 84

SERVICE
ELECTRIC SHOCK HAZARD.
Turn off all power to unit before servicing.
The ENABLE/OFF/REMOTE CONTACT
switch on control panel does not shut off con-
trol power; use field disconnect.
Electronic Components
CONTROL COMPONENTS — Unit uses an advanced elec-
tronic control system that normally does not require service.
For details on controls refer to Operating Data section.
30GTN,R040-110, AND 230B-315B UNIT CONTROL BOX
— When facing compressors, main control box is at left end
of unit. All incoming power enters through main box. Con-
trol box contains power components and electronic controls.
Outer panels are hinged and latched for easy opening. Re-
move screws to remove inner panels. Outer panels can
be held open for service and inspection by using door re-
tainer on each panel. To use door retainers: remove bottom
pin from door retainer assembly, swing retainer out horizon-
tally, and engage pin in one of the retainer ears and the hinge
assembly.
30GTN,R130-210, 230A-315A, AND 330A/B-420A/B UNIT
CONTROLAND MAIN POWER BOXES — The main power
box is on the cooler side of the unit, and the control box is
on the compressor side. Outer panels are hinged and latched
for easy opening. Remove screws to remove inner panels.
Compressors —
If lead compressor on either refriger-
ant circuit becomes inoperative for any reason, circuit is locked
off and cannot be operated due to features built into the elec-
tronic control system. Do not attempt to bypass controls to
force compressors to run.
COMPRESSOR REMOVAL — Access to the pump end
of the compressor is from the compressor side of the unit.
Access to the motor end of the compressor is from the inside
of the unit. All compressors can be removed from the com-
pressor side of the unit.
IMPORTANT: All compressor mounting hardware and
support brackets removed during servicing must be re-
installed prior to start-up.
Following the installation of the new compressor:
Tighten discharge valves to —
Compressor(s)
20 to 25 ft-lb (27 to 34 N-m) 06E250
80 to 90 ft-lb (109 to 122 N-m) 06E265,275,299
Tighten suction valves to —
80 to 90 ft-lb (109 to 122 N-m) 06E250
90 to 120 ft-lb (122 to 163 N-m) 06E265,275,299
Tighten the following fittings to —
120 in.-lb (13.5 N-m) High-Pressure Switch
OIL CHARGE (Refer to Table 28) — All units are factory
charged with oil. Acceptable oil level for each compressor is
from
1 ⁄
8
to 3 ⁄
8
of sight glass.
When additional oil or a complete charge is required, use
only Carrier-approved compressor oil.
Approved oils are as follows:
Petroleum Specialties, Inc. — Cryol 150 (factory oil charge)
Texaco, Inc.
— Capella WF-32
Witco Chemical Co. — Suniso 3GS
Table 28 — Oil Charge
COMPRESSOR
OIL REQUIRED
Pts L
06E250 14 6.6
06E265 19 9.0
06E275 19 9.0
06E299 19 9.0
Do not reuse drained oil or any oil that has been exposed
to atmosphere.
Cooler —
The cooler is easily accessible from the cooler
side of the unit. The refrigerant feed components are acces-
sible from the control box end of the unit.
COOLER REMOVAL — Cooler can be removed from the
cooler side of the unit as follows:
Open and tag all electrical disconnects before any work
begins. Note that cooler is heavy and both fluid-side and
refrigerant-side may be under pressure.
1. To ensure the refrigerant is in the condenser, follow this
procedure:
a. Open the circuit breakers and close the discharge valves
for the lag compressors in both circuits.
Do not close the discharge valve of an operating com-
pressor. Severe damage to the compressor can
result.
b. After the lag compressor discharge service valves have
been closed, close the liquid line service valve for one
circuit. Allow the lead compressor to pump down that
circuit until it reaches approximately 10 to 15 psig
(68.8 to 103.2 kPa).
c. As soon as the system reaches that pressure, shut down
the lead compressor by opening the compressor cir-
cuit breaker, then quickly close the discharge service
valve for that compressor.
d. Repeat the procedure for the other circuit.
2. Close the shutoff valves, if installed, in the cooler fluid
lines. Remove the cooler fluid piping.
3. Cooler may be under pressure. Open the air vent at the
top of the cooler, and open the drain on the bottom of the
cooler (near the leaving fluid outlet) to drain the cooler.
Both the drain and the air vent are located on the leaving
fluid end of cooler. See Fig. 22. Remove the cooler
waterside strainer.
4. Disconnect the conduit and cooler heater wires, if equipped.
Remove all thermistors from the cooler, being sure to la-
bel all thermistors as they are removed. Thermistor T1 is
a well-type thermistor, and thermistor T2 is immersed
directly in the fluid. See Fig. 22.
5. Remove the insulation on the refrigerant connection end
of the cooler.
6. Unbolt the suction flanges from the cooler head. Save the
bolts.
7. Remove the liquid lines by breaking the silver-soldered
joints at the cooler liquid line nozzles.
8. On 30GTN,GTR080-110 and 230B-315B units, remove
the vertical support(s) under the condenser coil in front
of the cooler. Provide temporary support as needed. Save
all screws for reinstallation later.
9. Remove the screws in the cooler feet. Slide the cooler
slightly to the left to clear the refrigerant tubing. Save all
screws.
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