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2. DISASSEMBLY INSTRUCTIONS
2.1 MECHANICAL PARTS
2.1.1 FRONT GRILLE Figure 1
1. Disconnect the unit from the power source.
2. Remove the two knobs by pulling them off.
Using a screwdriver, remove the screw that
secures the front grille to control board.
(See Figure 1)
3. Push the front grille up from the bottom.
Pull the top of the front grille away from the
cabinet as the top tabs lift out of their slots.
(See Figure 2)
Figure 2
4. Replace the grille by placing the tabs in the slots
and push the grille until it snaps into place.
Figure 3
2.1.2 CABINET
1. Disconnect the unit from the power source.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove 6 screws that secure the cabinet to the
base pan. (See Figure 3)
4. Lift the cabinet from the unit.
5. Re-install by referring to the procedures above.
Figure 4
2.1.3 CONTROL BOARD
1. Disconnect the unit from the power source.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove 2 screws that secure the control board to
base pan and orifice. (See Figure 4)
5. Pull the control board toward yourself.
NOTE : Controls, wires, and capacitor are now
accessible for servicing. Discharge the
capacitor before servicing. Figure 5
6. Disconnect one housing terminal and 3 wires for
the fan motor and compressor. (See Figure 5)
7. Re-install components by referring to procedures
above. (Refer to wiring diagram on page 20 in this
manual or inside control board.)
--5--
2.2 AIR HANDLING PARTS Figure 6
2.2.1 ORIFICE
1. Disconnect the unit from the power source.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove the control board.
(Refer to Section 2.1.3)
5. Remove 2 screws that secure the orifice.
(See Figure 6)
6. Lift orifice upward.
7. Re-install by referring to the procedures above.
Figure 7
2.2.2 BLOWER WHEEL, FAN AND SHROUD
1. Disconnect the unit from the power source.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove the control board.
(Refer to Section 2.1.3)
5. Remove the orifice. (Refer to Section 2.2.1)
6. Remove the screw that secures shroud and air
guide. (Figure 7)
7. Remove 2 screws that secure the base pan.
(See Figure 8)
8. Remove the screw that secures the shroud to Figure 8
channel of condenser.
9. Press the snap area of shroud with your thumbs.
This allows you to remove it from the condenser.
10. Lift the compressor upward with the evaporator
and condenser. (See Figure 8)
11. Remove the clamp springs which are clamped to
the boss of fan and blower wheel by hand plier.
(See Figure 9)
12. Pull the fan and blower wheel outward tilting it
foward yourself.
13. Remove the shroud.
14. Re-install by referring to the procedures above.
Figure 9
--6--
2.2.3 AIR GUIDE AND MOTOR
1. Disconnect the unit from the power source. Figure 10
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove the control board.
(Refer to Section 2.1.3)
5. Remove the orifice. (Refer to Section 2.2.1)
6. Remove the compressor, evaporator and
condenser. (Refer to Section 2.2.2)
7. Remove 2 screws that secure the motor to the air
guide. (See Figure 10)
8. Separate the motor by pulling it backward.
9. Remove 2 screws that secure the air guide to the
base fan. (See Figure 11)
10. Push the air guide backward and lift it upward.
(See Figure 11)
11. Re-install by referring to the procedures above.
Figure 11
2.3 ELECTRICAL PARTS
2.3.1 OVERLOAD PROTECTOR
1. Remove the cabinet. (Refer to Section 2.1.2) Figure 12 Figure 13
2. Remove the nut which fastens the terminal cover.
3. Remove the terminal cover.
4. Remove all the leads from the overload protector.
5. Remove the overload protector.
6. Re-install the components by referring to the
removal procedure above.
(See Figure 12 and 13)
--7--
2.3.2 COMPRESSOR
1. Remove the cabinet. (Refer to Section 2.1.2) Figure 14
2. Discharge the refrigerant by using a refrigerant
recovery system.
3. Remove the overload protector.
(Refer to Section 2.3.1)
4. After discharging the unit completely, unbrace the
suction and discharge pipes at the compressor
connections.
5. Remove 3 nuts which fasten the compressor.
6. Remove the compressor.
7. Re-install by referring to the removal procedure
above. (See Figure 14)
2.3.3 CAPACITOR
1. Remove the cabinet. (Refer to Section 2.1.2)
2. Remove the control board.
(Refer to Section 2.1.3)
3. Discharge the capacitor by placing a 20 K Figure 15
resistor across the capacitor terminals.
4. Remove the screw which fastens the capacitor
clamp. (See Figure 15)
5. Remove all the leads of capacitor terminals.
6. Remove the capacitor
7. Re-install the components by referring to the
removal procedure above.
2.3.4 THERMOSTAT
1. Remove the cabinet. (Refer to Section 2.1.2)
2. Remove the control board.
Figure 16
(Refer to Section 2.1.3)
3. Remove 2 screws which fasten the thermostat.
(See Figure 16)
4. Remove all the leads of the thermostat terminals.
5. Remove the thermostat.
6. Re-install the components by referring to the
removal procedure above.
2.3.5 ROTARY SWITCH
1. Remove the cabinet. (Refer to Section 2.1.2) Figure 17
2. Remove the control board.
(Refer to Section 2.1.3)
3. Remove 2 screws which fasten the rotary switch.
(See Figure 17)
4. Remove all the leads of the rotary switch
terminals.
5. Remove the rotary switch.
6. Re-install the components by referring to the
removal procedure above.
--8--
2.3.6 FAN MOTOR
1. Disconnect the unit from the power source. Figure 18
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove the control board.
(Refer to Section 2.1.3)
5. Remove the orifice. (Refer to Section 2.2.1)
6. Remove the compressor, evaporator, and
condenser. (Refer to Section 2.2.2)
7. Remove the fan and blower wheel.
(Refer to section 2.2.2)
8. Remove the motor. (Refer to Section 2.2.3)
9. Remove the air guide. (Refer to Section 2.2.3)
10. Re-install by referring to procedures above.
Figure 19
2.3.7 POWER CORD
1. Disconnect the unit from the power source.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove 2 screws that secure control board to
base pan and orifice (Refer to Section 2.1.3).
5. Pulls the control board toward you.
6. Disconnect the 2 receptacles and remove the
grounding screw.
7. Remove a screw securing the clip with cord to the
control board. (See Figure 19)
8. Pull the power cord.
9. Re-install by referring to procedures above.
Figure 20
2.4 REFRIGERANT CYCLE
2.4.1 CONDENSER
1. Remove the cabinet. (Refer to Section 2.1.2)
2. Discharge the refrigerant by using a refrigerant
recovery system.
3. Remove 2 screws which fasten the condenser.
(See Figure 20)
4. After discharging the refrigerant completely,
unbraze the interconnecting tube at the
condenser connections.
5. Remove the condenser.
6. Re-install by referring to the procedures above.
--9--
2.4.2 EVAPORATOR
1. Remove the cabinet. (Refer to Section 2.1.2) 6-3. Operate the vacuum pump for 20 to 30 minutes,
2. Discharge the refrigerant by using a refrigerant until 600 micron vacuum is obtained.
recovery system. Close valves A and B and observe vacuum
3. Remove the orifice. (Refer to Section 2.2.1) gauge for a few minutes.
4. After discharging the refrigerant completely, A rise in pressure would indicate a possible leak
unbraze the interconnecting tube at the evaporator or moisture remains in the system.
connections. With valves A and B closed, stop the vacuum
5. Remove the evaporator. pump.
6. Re-install by referring to the procedures above. 6-4. Remove the hose from the vacuum pump and
place it on the charging cylinder. See figure 23B.
2.4.3 CAPILLARY TUBE Open valve C.
1. Remove the cabinet. (Refer to Section 2.1.2) Discharge the line at the manifold connection.
2. Discharge the refrigerant by using a refrigerant 6-5. The system is now ready for final charging.
recovery system. 7. Recharge as follows :
3. Remove the orifice. (Refer to Section 2.2.1) 7-1. Rotary compressor systems are charged from
4. After discharging the refrigerant completely, the high-side. If the total charge cannot be put in
unbraze the interconnecting tube of the capillary the high-side, the balance will be put in the
tube. suction line through the access valve which is
5. Remove the capillary tube. installed as the system is opened.
6. Re-install by referring to the procedures above. 7-2. Connect the charging cylinder as shown in figure
21B. With valve C open, discharge the hose at
NOTES the manifold connection.
7-3. Open valve A and allow the proper charge to
Replacement of the refrigeration cycle.
enter the system. Valve B is still closed.
7-4. If more charge is required, the high-side will not
1. When replacing the refrigerating cycle, be sure to
take it. Close valve A.
discharge the refrigerant by using a refrigerant
7-5. With the unit running, open valve B and add the
recovery system.
balance of the charge.
2. After discharging the unit completely, remove the
a. Do not add the liquid refrigerant to the low-side.
desired components, and unbraze the pinch-off
b. Watch the low-side gauge, allow pressure to rise
tubes.
to 30 lbs.
3. Solder service valves into the pinch-off tube ports,
c. Turn off valve B and allow the pressure to drop.
leaving the valves open.
d. Repeat steps B and C until the balance of the
4. Solder the pinch-off tubes with service valves.
charge is in the system.
5. After doing the above procedures, the valve must
7-6. When the unit is operating correctly, use the
be closed and left in place on the system for any
pinch-off tool with the unit still running and the
subsequent procedures.
clamp on the pinch-off tube. Using a tube cutter,
6. Evacuate as follows:
cut the pinch-off tube about 2 inches from the
6-1. Connect the vacuum pump, as illustrated figure
pinch-off tool. Use sil-fos solder and solder the
21A.
pinch-off tube closed. Turn off the unit, allow
5-2. Start the vacuum pump. Slowly open manifold
setting for a while and then test the leakage of
valves A and B with two full turns counterclock-
the pinch-off connection.
wise and leave the valves closed.
The vacuum pump is now pulling through valves
A and B up to valve C by means of manifold and
the entire system.
CAUTION : If high vacuum equipment is used,
just crack valves A and B for a few minutes, then
open slowly with the two full turns counter-clock-
wise. This will keep oil from foaming and being
drawn into the vacuum pump.
--10--
Equipment needed: Vacuum pump, charging cylinder, manifold gauge, brazing equipment, pinch-off tool capable
of making a vapor proof seal, leak detector, tubing cutter, hand tools to remove components, service valve.
COMPOUND GAUGE
MANIFOLD
GAUGE
B A
CONDENSER
(HIGH PRESSURE SIDE) SEE INSETS
BELOW
COMPRESSOR
EVAPORATOR
(LOW PRESSURE SIDE)
CAPILLARY TUBE
LO HI CHARGING CYLINDER
A
B B A
EXTERNAL VACUUM PUMP
C
Figure 21A-Pulling Vacuum Figure 21B-Charging
--11--