Panasonic CW-C51GU User manual

Service Manual
Room Air Conditioner
CW-C51GU
CW-C61GU
WARNING
This service information is designed for experienced repair technicians only and is not designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.
Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to
service or repair the product or products deal with in this service information by anyone else could result in serious injury or death.
© 2002 Matsushita Electric Industrial co., Ltd.
All rights reserved. Unauthorized copying and
distribution is violation of law.
R
ORDER NO. RAC0111066C1
E 9

—2—
CONTENTS
1. PREFACE ...................................................................................................................................................3
1.1 FEATURES.....................................................................................................................................................3
1.2 SPECIFICATIONS .........................................................................................................................................3
1.3 LOCATIONS OF CONTROLS .......................................................................................................................4
1.4 SAFETY PRECAUTIONS ..............................................................................................................................4
1.5 INSULATION RESISTANCE TEST ................................................................................................................4
2. DISASSEMBLY INSTRUCTIONS ................................................................................................5
2.1 MECHANICAL PARTS ..................................................................................................................................5
2.1.1 FRONT GRILLE ....................................................................................................................................5
2.1.2 CABINET................................................................................................................................................5
2.1.3 CONTROL BOARD................................................................................................................................5
2.2 AIR HANDLING PARTS ................................................................................................................................6
2.2.1 AIR GUIDE UPPER ..............................................................................................................................6
2.2.2 ORIFICE, TURBO FAN AND FAN .........................................................................................................6
2.2.3 MOTOR..................................................................................................................................................7
2.2.4 AIR GUIDE.............................................................................................................................................7
2.3 ELECTRICAL PARTS ....................................................................................................................................7
2.3.1 OVERLOAD PROTECTOR ...................................................................................................................7
2.3.2 COMPRESSOR .....................................................................................................................................8
2.3.3 CAPACITOR ..........................................................................................................................................8
2.3.4 THERMOSTAT .......................................................................................................................................8
2.3.5 ROTARY SWITCH..................................................................................................................................8
2.3.6 POWER CORD .....................................................................................................................................9
2.4 REFRIGERANT CYCLE ................................................................................................................................9
2.4.1 CONDENSER .......................................................................................................................................9
2.4.2 EVAPORATOR ....................................................................................................................................10
2.4.3 CAPILLARY TUBE ..............................................................................................................................10
3. INSTALLATION ....................................................................................................................................12
3.1 SELECT THE BEST LOCATION .................................................................................................................12
3.2 HOW TO INSTALL .......................................................................................................................................12
3.3 ELECTRICAL DATA .....................................................................................................................................15
4. TROUBLESHOOTING GUIDE ....................................................................................................15
4.1 OUTSIDE DIMENSIONS..............................................................................................................................15
4.2 PIPING SYSTEM ........................................................................................................................................16
4.3 TROUBLESHOOTING GUIDE ....................................................................................................................17
5. CIRCUIT DIAGRAM ...........................................................................................................................22
6. EXPLODED VIEW ..............................................................................................................................23
7. SERVICE PARTS LIST ....................................................................................................................24

—3—
1. PREFACE
This service manual provides various service information, including the mechanical and electrical parts, etc.
This room air conditioner was manufactured and assembled under a strict quality control system.
The refrigerant is charged at the factory. Be sure to read the safety precautions prior to servicing the unit.
1.1 FEATURES
• DESIGNED FOR COOLING ONLY
• POWERFUL AND INCREDIBLE COOLING
• BUILT-IN ADJUSTABLE THERMOSTAT
• WASHABLE ONE-TOUCH FILTER
• COMPACT SIZE
1.2 SPECIFICATIONS
MODELS
ITEMS
COOLING CAPACITY (BTU/h) 5,250 6,000
POWER SUPPLY (Phase, V, Hz) 1ø, 115V, 60HZ
INPUT (W) 540 620
OPERATING CURRENT (AMP.) 5.0 5.8
REFRIGERANT CONTROL CAPILLARY TUBE
REFRIGERANT CHARGE (R-22) 220g (7.8 Oz) 235g (8.3)
INSIDE FAN TURBO
OUTSIDE FAN PROPELLER FAN WITH SLINGER RING
AIR DISCHARGE 2-WAY (RIGHT AND LEFT)
CHASSIS TOP-DOWN
PROTECTOR
TEMPERATURE CONTROL THERMOSTAT
ROTARY SWITCH 5 POSITIONS (LOW FAN, HIGH FAN, OFF, HIGH COOL, LOW COOL)
FAN MOTOR 6 POLES, 19.9W 6 POLES, 20.9W
• OVERLOAD PROTECTOR FOR COMPRESSOR
• INTERNAL PROTECTOR FOR FAN MOTOR
CW-C51GU CW-C61GU
• NOTE: Specifications are subject to minor change without notice for further improvement.

—4—
1.3 LOCATIONS OF CONTROLS
1.4 SAFETY PRECAUTIONS
1. When servicing, set the ROTARY SWITCH to
Off and unplug the power cord.
2. Observe the original lead dress.
If a short circuit is found, replace all parts which
have been overheated or damaged by the short cir-
cuit.
3. After servicing, make an insulation resistance test
to prevent the customer's exposure to shock
hazards.
1.5 INSULATION RESISTANCE TEST
1. Unplug the power cord and connect a jumper
between 2 pins (black and white).
2. The grounding conductor (green or green and yel-
low) is to be open.
3. Measure the resistance value with an ohm meter
between the jumpered lead and each exposed
metallic part on the equipment at all positions
[except Off] of the ROTARY SWITCH.
4. The value should be over 1 MΩ.
CAUTION : After switching the air conditioner from Cool to Off or Fan, wait at least 3 minutes before switching it
back to Cool.
Off
— Turns air conditioner off.
High Fan — High speed fan operation
without cooling.
Low Fan — Low speed fan operation
without cooling.
High Cool — Cooling with high speed fan
operation.
Low Cool — Cooling with low speed fan
operation.
This automatically controls the temperature of
the indoor air.
Turn the knob so that the arrow points to the
larger marks for greater cooling. Point the
arrow to the smaller marks for more moderate
cooling.
(i.e. the higher the number, the greater the
cooling)
FAN
HIGH
LOW LOW
HIGH
COOLOFF
HIGH
FAN
LOW
FAN
HIGH
COOL
LOW
COOL
OFF
1
2
3
4567
8
9
10
THERMOSTAT
C
O
O
L
E
R
1
2
3
4567
8
9
10
TEMP CONTROL
C
O
O
L
E
R

—5—
2. DISASSEMBLY INSTRUCTIONS
2.1 MECHANICAL PARTS
2.1.1 FRONT GRILLE
1. Disconnect the unit from source of power.
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)
4. Replace the grille by placing the tabs in the slots
and push the grille until it snaps into place.
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 9 screws that secure the cabinet to the
base pan and condenser. (See figure 3)
4. Lift the cabinet from the unit.
5. Re-install by referring to the procedures above.
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 air guide. (See Figure 4)
5. Pull the control board toward yourself.
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 23 in this
manual or inside control board.)
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
NOTE : Controls, wires, and capacitor are now
accessible for servicing. Discharge the
capacitor before servicing. See step
2.3.3 on page 8 for procedures.

—6—
2.2 AIR HANDLING PARTS
2.2.1 AIR GUIDE UPPER
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 air guide upper
to air guide lower. (See Figure 6)
6. Lift air guide upper upward.
7. Re-install by referring to the procedures above.
2.2.2 ORIFICE, TURBO FAN AND FAN
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 air guide upper.
(Refer to Section 2.2.1)
6. Remove 2 screws that secure the base pan to
condenser. (See Figure 7)
7. Remove screw that secures the shroud to
channel of condenser.
8. Press the snap area of shroud with your thumbs.
This allows you to remove it from the condenser.
9. Lift the compressor upward with the evaporator
and condenser. (See Figure 7)
10. Remove the orfice by pushing the snap area of
the air guide blower. (See Figure 8)
11. Remove the clamp springs which are clamped to
the boss of fan and turbo fan by hand plier. (See
Figure 9)
12. Pull the fan and turbo fan outward.
13. Remove the shroud.
14. Re-install by referring to the procedures above.
Figure 6
Figure 7
Figure 8
Figure 9

—7—
2.2.3 MOTOR
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 air guide upper.
(Refer to Section 2.2.1)
6.
Remove the compressor, turbo fan, fan and
shroud. (Refer to Section 2.2.2)
7.
Remove 2 screws that secure the motor to the
motor. (See figure 10)
8. Remove the motor.
9. Re-install by referring to the procedures above.
2.2.4 AIR GUIDE
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 air guide upper.
(Refer to Section 2.2.1)
6. Remove the compressor, turbo fan, fan and
shroud. (Refer to Section 2.2.2)
7.
Remove the motor. (Refer to
Section 2.2.3)
8. Remove 2 screws that secure the air guide to the
base pan. (See Figure 11)
9. Push the air guide backward and lift it upward.
(See Figure 11)
10. Re-install by referring to the procedures above.
2.3 ELECTRICAL PARTS
2.3.1 OVERLOAD PROTECTOR
1. Remove the front grille and cabinet.
(Refer to Section 2.1)
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)
Figure 10
Figure 12 Figure 13
Figure 11

—8—
2.3.2 COMPRESSOR
1. Remove the front grille and cabinet.
(Refer to Section 2.1)
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 KΩ
resistor across the capacitor terminals.
4. Remove the screw which fastens the capacitor
clamp.
5. Remove all the leads of capacitor terminals.
6. Re-install the components by referring to the
removal procedure above. (See Figure 15)
2.3.4 THERMOSTAT
1. Remove the cabinet. (Refer to Section 2.1.2)
2. Remove the control board.
(Refer to Section 2.1.3)
3. Remove 2 screws which fasten the thermostat.
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. (See Figure 16)
2.3.5 ROTARY SWITCH
1. Remove the cabinet. (Refer to Section 2.1.2)
2. Remove the control board.
(Refer to Section 2.1.3)
3. Remove 2 screws which fasten the rotary switch.
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. (See Figure 17)
Figure 14
Figure 15
Figure 16
Figure 17

—9—
2.3.6 POWER CORD
1. Disconnect the unit from source of power.
2. Remove the front grille. (Refer to Section 2.1.1)
3. Remove the cabinet. (Refer to Section 2.1.2)
4. Remove a screw that secures control board to
base pan. (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.
8. Pull the power cord.
9. Re-install by referring to procedures above.
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 the air guide. (Refer to Section 2.2.1)
4. Remove 2 screws which fasten the condenser.
5. After discharging the refrigerant completely,
unbraze the interconnecting tube at the
condenser connections.
6. Remove the condenser.
7. Re-install by referring to the procedures above.
Figure 18
Figure19

2.4.2 EVAPORATOR
1. Remove the cabinet.
2. Discharge the refrigerant by using a refrigerant
recovery system.
3. Remove the air guide upper. (Refer to Section
2.2.1)
4. After discharging the refrigerant completely,
unbraze the interconnecting tube at the condenser
connections.
5. Remove the evaporator.
6. Re-install by referring to the procedures above.
2.4.3 CAPILLARY TUBE
1. Remove the cabinet.
2. Discharge the refrigerant by using a refrigerant
recovery system.
3. Remove the air guide upper. (Refer to Section
2.2.1)
4. After discharging the refrigerant completely,
unbraze the interconnecting tube of the capillary
tube.
5. Remove the capillary tube.
6. Re-install by referring to the procedures above.
NOTES
Replacement of the refrigeration cycle.
1. When replacing the refrigerating cycle, be sure to
discharge the refrigerant by using a refrigerant
recovery system.
2. After discharging the unit completely, remove the
desired components, and unbraze the pinch-off
tubes.
3. Solder service valves into the pinch-off tube ports,
leaving the valves open.
4. Solder the pinch-off tubes with service valves.
5. After completing the above procedures, the valve
must be closed and left in place on the system for
any subsequent procedures.
6. Evacuate as follows:
6-1. Connect the vacuum pump, as illustrated in
figure 21A.
6-2. Start the vacuum pump. Slowly open manifold
valves A and B with two full turns counter-
clockwise 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.
6-3. Operate the vacuum pump for 20 to 30 min-
utes, until 600 micron vacuum is obtained.
Close valves A and B and observe vacuum
gauge for a few minutes.
A rise in pressure would indicate a possible
leak or moisture remaining in the system.
With valves A and B closed, stop the vacuum
pump.
6-4. Remove the hose from the vacuum pump and
place it on the charging cylinder. See figure
23B. Open valve C.
Discharge the line at the manifold connection.
6-5. The system is now ready for final charging.
7. Recharge as follows:
7-1. Rotary compressor systems are charged from
the high-side. If the total charge cannot be put
in the high-side, the balance will be put in the
suction line through the access valve which is
installed as the system is opened.
7-2. Connect the charging cylinder as shown in fig-
ure 21B. With valve C open, discharge the
hose at the manifold connection.
7-3. Open valve A and allow the proper charge to
enter the system. Valve B is still closed.
7-4. If more charge is required, the high-side will
not take it. Close valve A.
7-5. With the unit running, open valve B and add
the balance of the charge.
a. Do not add the liquid refrigerant to the low-
side.
b. Watch the low-side gauge, allow pressure to
rise to 30 lbs.
c. Turn off valve B and allow the pressure to
drop.
d. Repeat steps B and C until the balance of
the charge is in the system.
7-6. When the unit is operating correctly, use the
pinch-off tool with the unit still running and the
clamp on the pinch-off tube. Using a tube cut-
ter, cut the pinch-off tube about 2 inches from
the pinch-off tool. Use sil-fos solder and solder
the pinch-off tube closed. Turn off the unit,
allow setting for a while and then test the leak-
age of the pinch-off connection.
—10—

—11—
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 and service valve.
BA
BA
BA
COMPOUND GAUGE
SEE INSETS
BELOW
CAPILLARY TUBE
EVAPORATOR
(LOW PRESSURE SIDE)
COMPRESSOR
CONDENSER
(HIGH PRESSURE SIDE)
EXTERNAL VACUUM PUMP
LO HI CHARGING CYLINDER
MANIFOLD
GAUGE
C
Figure 21A-Pulling Vacuum Figure 21B-Charging

—12—
3. INSTALLATION
This air conditioner is designed with a button-down
chassis so it can be easily installed in a window.
3.1 SELECT THE BEST LOCATION
1. To prevent vibration and noise, make sure the unit is
installed securely and firmly.
2. Install the unit where the sun does not shine directly
on the unit.
3. The outside of the cabinet must extend outward for at
least 10" and there should be no obstacles, such as a
fence or wall, within 20" from the back of the cabinet
because it will prevent heat radiation of the condenser.
Restriction of outside air will greatly reduce the cooling
efficiency of the air conditioner.
4. Install the unit slanted slightly so the back is slight-
ly lower than the front (about 1/4"). This will force
condensed water to the outside.
5. Install the unit with the bottom about 30"~60"
above the floor level.
3.2 HOW TO INSTALL
3.2.1 WINDOW REQUIREMENTS
NOTE: All supporting parts should be secured to firm
wood, masonry, or metal.
1. This unit is designed for installation in standard double
hung windows with actual opening widths of 22" to 36".
The upper and lower sash must open sufficiently to allow
a clear vertical opening of 13" from the bottom of the
sash to the window stool.
2.If a storm window presents interference, fasten a 2" wide
wood strip to the inner window sill across the full width of
the sill. The wood strip should be thick enough to raise
the height of the window sill so that the unit can be
installed without interference by the storm window frame.
See Fig. 24. Top of the wood strip should be approxi-
mately 3/4" higher than the storm window frame (STORM
WINDOW FRAME) or wood strip (OUTDOORS) to help
condensation to drain properly to the outside.
3. Install a second wood strip (approximately 6" long by 11/2"
wide and same thickness as first strip) in the center of the
outer sill flush against the back off the inner sill. This will
raise the L bracket as shown Fig. 24.
The thickness of the second wood strip may not be the same
as the first wood strip.
The thickness of the second wood strip must be defined to
keep the 3/4inch distance between the inner sill or the top of
the first wood strip and the outer sill.
ABOUT / "
Over 20"
HEAT
RADIATION
FENCE
AWNING
OUTSIDE
INSIDE
COOLED AIR
30"-60"
14
Figure 22
Figure 23
Figure 24
All side louvers of the cabinet must remain
exposed on the outdside of the structure.
CAUTION
OUTDOORSINDOORS
INNER
SILL
OUTER
SILL
INNER
SILL
WOOD STRIP MOUNTED
ON TOP OF INNER SILL
WOOD STRIP
FOR
L BRACKET
3/4"
CLEARANCE
1"
STORM
WINDOW
FRAME
OUTDOORSINDOORS
OUTER
SILL

—13—
Installation
3.2.2 BEFORE INSTALLATION
1. Insert the guide panels into the guides of the air condition-
er. Fasten the curtains to the unit with screws (TYPE A),
as shown Fig. 25.
2. Cut the adhesive-backed seal strip (TYPE D) to the win-
dow width.
Remove the backing from the seal strip and attach the
seal strip to the underside of the bottom window. (Fig. 26)
3.2.3 NOW START INSTALLATION
1. LOCATING UNIT IN A WINDOW
Open the window and mark center line on the center of
the inner sill, as shown in Fig. 27.
2. ATTACH LBRACKET
a. Install the Lbrackets behind the inner window sill, with
the short side of bracket as shown.
Use the 2 screws (TYPE A) provided.
b. The bracket helps to hold unit securely in place. Be
sure to place bracket edge flush against back of inner
sill. See Fig. 27.
TYPE B: 4EA
(WOOD SCREW)
HARDWARE
TYPE A: 11EA
(SHORT SCREW) TYPE C: 3EA ( L BACKET) DRAIN PIPE
TYPE E: 1EA
(SASH SEAL)
(Not adhesive backed)
TYPE D: 1EA
(SEAL STRIP)
(Adhesive backed)
TYPE F: 2EA
(GUIDE PANEL)
10mm
16mm
TYPE G: 1EA
(SUPPORT BRACKET)
During the following step, hold unit firmly until
window sash is lowered to top channel behind
side panel frames. Personal injury or property
damage may result if unit falls from window.
ROOM SIDE
CENTER LINE
INNER SILL
SEAL STRIP
(TYPE D)
TYPE A
TYPE A
Figure 25
Figure 26
Figure 27
CAUTION

3. INSTALL THE AIR CONDITIONER IN THE WINDOW
a. Carefully lift the air conditioner and slide it into the
open window. Make sure the bottom guide of the air
conditioner drops into the notches of the
Lbracket. See Fig. 28.
IMPORTANT :
When the air conditioner drops into the Lbracket, the air
conditioner will be centered in window opening as shown in
Fig. 29.
b. While steadying the air conditioner, carefully bring the
window sash down behind the upper guide of the air
conditioner, as shown in Fig. 30.
4. SECURE THE GUIDE PANELS
Extend the guide panels (TYPE F) to fill the window
opening using 4 screws (TYPE B) to secure them, as
shown in Fig. 31.
5. INSTALL THE SASH SEAL AND SASH LOCK
a. Cut the sash seal (TYPE E) to the window width. Stuff
the sash seal between the glass and the window to
prevent air and insects from getting into the room, as
shown in Fig. 31.
b. Fasten the Lbracket using a screw (TYPE A), as
shown in Fig. 31.
6. a. Remove the screws that secure the cabinet and base
pan in the right side.
b. Fasten the suport bracket (TYPE G) using a removed
screw. Attach the suport bracket (TYPE G) in the inner
window sill with a screw (TYPE B), as shown Fig. 32.
7. Window installation of room air conditioner is now
completed. See ELECTRICAL DATA for attaching
power cord to electrical outlet.
3.2.4 How to Secure the Drain pipe
In humid weather, excess water may cause the BASE
PAN to overflow. To drain the water, remove the DRAIN
CAP and secure the DRAIN PIPE to the rear hole of the
BASE PAN. (Fig. 33) Press the drain pipe into the hole
by pushing down and away from the fins to avoid injury.
—14—
CENTER LINE
SEAL
WINDOW FRAME
BOTTOM
GUIDE
ABOUT 1/4"
L BRACKET
UPPER GUIDE
DRAIN PIPE
DRAIN CAP
hang push
TYPE B
SASH SEAL
(TYPE E)
LBRACKET
TYPE A
OUTSIDE
INSIDE
L BRACKET
OUTER SILL
SHORT SIDE
INNER SILL
TYPE A
8" 8"
CENTER LINE
TYPE B
Support Bracket (TYPE G)
Figure 28
Figure 29
Figure 30
Figure 31
Figure 32
Figure 33

—15—
REMOVAL FROM WINDOW
Turn the air conditioner off, disconnect the power cord, remove the Support Bracket, Lbracket and the screws installed through
the top and bottom of the guide panels, and save for reinstallation later. Close the guide panels. Keeping a firm grip on the air
conditioner, raise the sash, and carefully tilt the air conditioner backward, draining any condensate. Lift the air conditioner from
the window and remove the sash seal from between the windows.
3.3 ELECTRICAL DATA
USE OF EXTENSION CORDS
Because of potential safety hazards, we strongly discourage the use of an extension cord. However, if you wish to use an extension
cord, use a CSA certified/UL-listed 3-wire (grounding) extension cord, rated 15A, 125V.
Do not under any
circumstances cut
or remove the
grounding prong
from the plug.
Line Cord Plug Use Wall Receptacle Power Supply
Power supply cord with
3-prong grounding plug Standard 125V, 3-wire grounding receptacle rated 15A, 125V AC
Use 15 AMP, time
delay fuse, or circuit
breaker.
4. TROUBLESHOOTING GUIDE
4.1 OUTSIDE DIMENSIONS (unit: mm [in])
370 (14 9/16")
312 (12 9/32")
370 (14 9/16")
312 (12 9/32")
29 (1 5/32")
120 (4 3/4")
27.5 (1 3/32")
346 (13 5/8")
472 (18 9/16") 42 (1 21/32")
42 (1 21/32")
155(6 3/32")
12
(0.4
1/16
")
472 (18 9/16")
22.5(0.8 3/32")
FAN
HIGH
LOW LOW
HIGH
COOLOFF
1
2
3
4567
8
9
10
THERMOSTAT
C
O
O
L
E
R
FAN
HIGH
LOW LOW
HIGH
COOLOFF
1
2
3
4567
8
9
10
THERMOSTAT
C
O
O
L
E
R

—16—
4.2 PIPING SYSTEM
Following is a brief description of the important components and their function in what is called the refrigeration
system. Reference should be made to Figure 34 to follow the refrigerating cycle and the flow of the refrigerant in
the cooling cycle.
COOLED
AIR
HOT
DISCHARGED
AIR
MOTOR
COMPRESSOR
ROOM AIR HEAT LOAD
CAPILLARY TUBE
(LIQUID REFRIGERANT)
LIQUID OUTLET
VAPOR INLET
COMPLETE LIQUID
BOIL OFF POINT
SUCTION LINE
COOL LOW PRESSURE VAPOR
LIQUID
PRESSURE
DROP
DISCHARGE
LINE
NOT HIGH PRESSURE
VAPOR
OUTSIDE COOLING
AIR FOR REFRIGERANT
PASS THROUGH
EVAPORATOR COILS CONDENSER COILS
ROOM AIR CONDITIONER
CYCLE OF REFRIGERATION
HIGH PRESSURE VAPOR
LIQUID REFRIGERANT
LOW PRESSURE VAPOR
OIL
CONDENSER COILS
FAN
MOTOR
CAPILLARY
TUBE
TURBO FAN
EVAPORATOR
COILS
Figure 34

—17—
4.3 TROUBLESHOOTING GUIDE
In general, possible trouble is classified in two kinds.
The one is called Starting Failure which is caused by an electrical defect. The other is Ineffective Air Con-
ditioning caused by a defect in the refrigeration circuit and improper application.
Unit is running but cooling is ineffective.
Ineffective Cooling
Satisfactory operation
with temperature
difference of inlet & outlet
air; 55~59°F (13~15°C)
Replacement of unit if
the unit is beyond repair.
Check outdoor coil
(heat exchanger) and
fan operation.
Check heat load
increase.
Check cold air
circulation for smooth
flow.
Check gas leakage. Clean condenser.
Not on separate circuit
Check inside gas
pressure.
Adjust refrigerant
charge.
Malfunction of
compressor.
Replacement of
compressor.
Check clogging in refrigera-
tion circuit.
Repair clogging in
refrigeration circuit.
Dirty indoor coil
(heat exchanger)
Repair gas leak.
Malfunction of fan.
Clogging of air filter.
Obstruction at air outlet.
Remove obstruction.

—18—
Fails to Start
Improper thermostat
setting
Loose terminal
connection
Improper wiring
Check of power source.
Drop of power voltage.
Capacitor check.
Replacement.
Check of control switch
setting.
Compressor fails only to
start.
Defect of compressor
capacitor.
Replacement of compressor
(Motor damaged).
Irregular motor insulation (Ω)
Irregular motor resistance (Ω)
Check of circuit breaker
and fuse.
Gas leakage of feeler
bulb of thermostat.
Check control switch.
Fan only fails to start.
Improper wiring.
Defect of fan motor
capacitor.
Replacement of fan motor.
Regular but fails to start.
Replacement of compressor.
(Locking of piston, metal.)
Irregular motor
resistance (Ω)
Irregular motor
insulation (Ω)

—19—
ROOM AIR CONDITIONER VOLTAGE LIMITS
NAME PLATE RATING MINIMUM MAXIMUM
115V ± 10% 103.5V 126.5V
COMPLAINT CAUSE REMEDY
Fan motor will not run. No power Check voltage at outlet. Correct if none.
Power supply cord Check voltage to rotary switch. If none, check
power supply cord. Replace cord if circuit is
open.
Rotary switch Check switch continuity. Refer to wiring diagram
for terminal identification. Replace switch if
defective.
Wire disconnected or Connect wire. Refer to wiring diagram for
connection loose terminal identification. Repair or replace loose
terminal.
Capacitor (Discharge Test capacitor.
capacitor before testing.) Replace if not within ±10% of manufacturer's
rating. Replace if shorted, open, or damaged.
Will not rotate Fan blade hitting shroud or blower wheel hitting
scroll. Re-align assembly.
Units using slinger ring condenser fans must
have 0.22~0.25 inch clearance to the base.
If necessary, shim up the bottom of the fan motor
with mounting screw(s).
Check fan motor bearings; if motor shaft will not
rotate, replace the motor.
Fan motor runs. Revolves on overload Check voltage. See limits on this page.
If not within limits, call an electrician.
Test capacitor.
Check bearings. Does the fan blade rotate
freely?
If not, replace fan motor.
Pay attention to any change from high speed to
low speed. If the speed does not change,
replace the motor.

—20—
COMPLAINT CAUSE REMEDY
Fan motor noise. Fan If cracked, out of balance, or partially missing,
replace it.
Blower If cracked, out of balance, or partially missing,
replace it.
Loose set screw Tighten it.
Worn bearings If knocking sounds continue when running or
loose, replace the motor. If the motor hums or
noise appears to be internal while running,
replace motor.
Compressor will not run, Voltage Check voltage. See the limits on the preceding
fan motor runs. page. If not within limits, call an electrician.
Wiring Check the wire connections; if loose, repair or
replace the terminal. If the wires are discon-
nected, refer to wiring diagram for identification,
and replace the wires. Check the wire connections;
If not according to the wiring diagram, correct
the connections.
Rotary Check for continuity, refer to the wiring diagram
for terminal identification. Replace the switch if
the circuit is open.
Thermostat Check the position of knob. If not at the coldest
setting, advance the knob to this setting and
restart the unit.
Check the continuity of the thermostat. Replace
the thermostat if the circuit is open.
Capacitor (discharge Check the capacitor.
capacitor before Replace if not within ±10% of manufacturer’s
servicing.) rating, replace if shorted, open, or damaged.
Compressor Check the compressor for open circuit or
ground. If open or grounded, replace the
compressor.
Overload Check the compressor overload if externally mounted.
Replace if open. (If the compressor temperature is
high, remove the overload, cool, and retest.)
Compressor cycles on Voltage Check the voltage. See the limits on the
overload. preceding page. If voltage is not within these limits,
call an electrician.
Overload Check overload, if externally mounted.
Replace if open. (If the compressor temperature
is high, remove the overload, cool, and retest.)