6--7
T-334
6.4.7 Adding Refrigerant to System (Partial
Charge)
a. Examine the unit refrigerant system for any evidence
of leaks. Repair as necessary.
b. Maintain the conditions outlined in paragraph 6.4.5.
c. Connect charging line between suction line and cylin-
der of refrigerant R-134a. Open VAPOR valve.
d. Slowly add charge until the liquid appears at the prop-
er level.
6.5 COMPRESSOR
WARNING
Make sure power to the unit is OFF and
power plug disconnected before replacing
the compressor.
WARNING
Before disassembly of the compressor
make sure to relieve the internal pressure
very carefully by slightly loosening the cou-
plings to break the seal.
CAUTION
The scroll compressor achieves low suc-
tion pressure very quickly. Do not use the
compressor to evacuate the system below
zero psig. Never operate the compressor
with the suction or discharge service valves
closed (frontseated). Internal damage will
result from operating the compressor in a
deep vacuum.
6.5.1 Removal and Replacement of Compressor
NOTE
Service compressor contains a nitrogen
charge. Due to the hygroscopic nature of the oil,
time the compressor is left open to the atmo-
sphere should be minimized as much as pos-
sible.
a. Procure a replacement compressor kit. A list of items
contained in the compressor kit is provided in
Table 6--1.
b. Turn the unit start-stop switch (ST) and unit circuit
breaker (CB-1) OFF, and disconnect power to the
unit.
c. Remove the compressor guard or the protective
guard from the lower section and evacuate the unit.
Refer to Section 6.4.4.
d. Carefully remove and discard the rubber gasket that
was located between the terminal box and the com-
pressor shell.
e. Remove and discard the rubber gasket that was lo-
cated between the terminal box and the compressor
shell.
f. Remove the rotalock fittings from the suction, dis-
charge and economizer service connections.
Table 6--1 Compressor Kit
Item
Component
1
Compressor
2
Service Connection Teflon Seal
3
Service Connection Teflon Seal
4
Mylar Washers
5
Wire Tie
6
Oil Sight Glass Plug
7
Resilient Mount
8
Terminal Box Rubber Gasket
9
SST Washers
10
Schrader valve/ valve body*
11
Oil -Mobil 32ST (32 oz can)
12
Upper Shock Mount (Ring)
13
Upper Shock Mount (Bushing)
14
Oil Charge Warning Label
15
Mylar Protector
16
Fitting Assy Elbow**
17
Terminal Box Screws
* Schrader valve is not used on semi-hermetic units
**Elbow fitting (Item 16) is used on units with oil separa-
tor.
g. Remove the entire compressor-upper mount bracket,
by removing the four cap screws from the wall side
and the 32 mm (1 1/4 in.) bolt from the compressor
side. See Figure 6--6.
h. Replace the upper mounting bracket shock mount
ring and busing (kit items #12 and 13). Reassemble
the bracket in the same manner as the original and
torque the shoulder bolt to 2.8 mkg (20 ft-lbs.).
i. Remove the rubber plugs from the service ports of the
new compressor, and plug the service ports of the
compressor to be removed. Remove the old com-
pressor from the unit. Return the rubber plugs to the
new compressor immediately after the old compres-
sor is removed from the unit.
1
2
3
4
5
6
1. 32 mm Bolt
2. Mylar Protector
(kit item #14)
3. Upper Shock Mount
Bushing (kit item #9)
4. Upper Shock Mount
Ring (kit item #8)
5. Shoulder Bolt
6. 9.5 mm (0.375 in.)
Figure 6--6 Compressor Upper Mounting
Downloaded from
