58
6. Remove loader (mark solenoids no. 1 and 2 for replace-
ment) and oil solenoids and high-pressure switch from
compressor. Using 2 wrenches, carefully remove the oil
pressure transducer from the compressor. These will all
be reconnected to the replacement compressor.
NOTE: Some oil will leak out of the transducer fitting
when the transducer is removed. See Fig. 30.
7. Mark motor temperature leads (2 blue wires) and remove
from quick connect terminals in the junction box.
8. Remove the 2 bolts securing the motor cooling/econo-
mizer line flange to the compressor.
9. Remove the four M14 bolts securing the discharge line
flange to the compressor. Two of the bolts also secure the
mounting bracket for the external oil filter. Support the oil
line to prevent damage to the line while the compressor is
being changed. For 30GX units, place temporary protec-
tion over coils to prevent fin and tube damage.
10. Move lifting apparatus into place and attach to the 2 lift-
ing rings on the compressor. Apply minimal tension
to hold the compressor while the remaining bolts are
removed.
11. Remove the
3
/
8
-in. holddown bolt securing the foot at the
discharge end of the compressor to the mounting bracket
on the cooler. A foot bracket will be mounted to the
replacement compressor.
12. Remove the 4 lockwashers and nuts securing the
compressor to the suction flange of the cooler. The com-
pressor is held in place using four M14 x 2 studs through
the suction nozzle of the cooler. The studs have an E-12
external Torx drive head. If possible, remove studs; if
studs hit the cooler insulation, leave them in place — they
will not interfere with compressor removal or installation.
Save all the hardware as it will be needed to install the
replacement compressor.
13. After checking to ensure all lines, wires, conduits, etc. are
free and out of the way, remove compressor from cooler.
Apply a light film of O-ring grease to new O-ring and
place back into groove in mounting flange of compressor.
If the new compressor is the A1/A2 (30HX units), A2
(30GXN,R204-268 units) or B2 (30GXN,R281-350
units) compressor, remove the compressor junction box
and rotate it 180 degrees. Tighten screws to 6.8 to
9.5 N-m (5 to 7 ft-lb). The A1 and A2 compressors are on
the right side of the unit when facing the unit control box.
14. Remove suction cover plate and bolts from new compres-
sor and set compressor on unit flange. Thread the studs all
the way back into the compressor. Install the 4 lock wash-
ers and nuts finger-tight. Tighten bolts in a crossing
pattern to a range of 81.4 to 135.6 N-m (60 to 100 ft-lb).
Do NOT overtighten as damage may result to O-ring.
Install and tighten holddown bolt in mounting foot.
15. Remove motor cooling/economizer and discharge line
cover plates from new compressor.
16. Apply a light film of O-ring grease to motor cooling/
economizer and discharge line O-rings, place back into
grooves and install flange bolts. Tighten discharge line
bolts in a crossing pattern to a range of 81.4 to 135.6 N-m
(60 to 100 ft-lb). Tighten motor cooling/economizer bolts
to a range of 81.4 to 108.5 N-m (60 to 80 ft-lb). Do NOT
overtighten as damage may result to O-rings.
17. Reconnect the oil filter to the shutoff valve and oil line to
the compressor. Install oil line straight into fitting until
ferrule seats against fitting. Thread packing nut onto
fitting and tighten finger tight. Use a backup wrench to
finish tightening the nut. Do not overtighten.
18. Reinstall the loader and oil solenoids, high-pressure
switch, and oil pressure transducer. Make sure the loader
solenoids are installed on the correct number loader.
19. Reconnect conduits back into compressor junction box.
Reconnect all wiring that was removed in Steps 4, 5, and 7.
Temporarily install the reverse rotation low pressure
switch that is supplied with the replacement compressor.
Connect the switch to the second high pressure port using a
standard
1
/
4
-in. service hose. The switch will not reset until
10 psig of pressure is present on the switch. Temporarily
wire the reverse rotation low pressure switch in series with
the compressor’s high pressure switch as shown in Fig. 32.
20. Leak check compressor and refrigerant lines with nitro-
gen. Repair any leaks found. Remove nitrogen from
system. Evacuate compressor and refrigerant lines. Refer
to the Refrigerant Charging/Adding Charge and Oil
Charging/Low Oil Recharging sections on pages 55 and
56 for recharging procedures.
21. Open all shutoff valves and leak check the circuit and all
fittings and joints. Repair any leaks found.
22. Reset the reverse rotation low pressure switch.
23. Restore main and control power to the machine. Put the
Enable/Off/Remote Contact switch in the Enable posi-
tion. Using the Navigator under the Service Test mode,
turn the TEST sub-mode ‘On’. Under the OUTS
sub-mode, test each compressor’s oil and motor cooling
solenoids (items ‘MC.A1’, ‘OS.A1’, etc.). Next, locate
and test each loader solenoid under the COMP sub-mode
(items ‘LD.A1’, etc.). It is important that the loaders are
located properly (loader 1 on right hand side when
viewed from side opposite control box on 30HXA,HXC
units, on left hand side when reaching over compressor to
far side on 30GXN,R units).
The next steps involve compressor unbolting and removal.
Compressor seals are made using O-rings. Use care when
removing bolts and disconnecting flanges. The O-rings
must NOT be re-used. New O-rings are provided with the
replacement compressor.
The 06N screw compressors
weigh approximately 920 lb (417 kg).
Be sure that an
appropriate lifting cart or hoist is used to avoid injury.
See Fig. 31 for lifting locations and center of gravity
dimensions. Make sure compressor is properly rigged
before unbolting.
CENTER OF GRAVITY
OF COMPRESSOR
MINIMUM
300 mm
(11.8 in.)
MINIMUM
384 mm
(15.1 in.)
COMPRESSOR LIFTING MECHANISM
COMPRESSOR SIDE
MOTOR SIDE
NOTE: Locate strap from center of gravity lifting ring and support
motor casing to provide 3-point level rigging.
Fig. 31 — Compressor Lifting Diagrams
LIFTING LUGS BOTH OUTSIDE EDGES
EQUIDISTANT FROM GEAR COVER END
