Mitsubishi Electric SLZ Series Operating manual

TECHNICAL & SERVICE MANUAL
CONTENTS
1. REFERENCE MANUAL ...................... 2
2. SAFETY PRECAUTION ......................2
3. PARTS NAMES AND FUNCTIONS..... 6
4. SPECIFICATIONS ...............................7
5. OUTLINES AND DIMENSIONS........... 9
6. WIRING DIAGRAM............................10
7. REFRIGERANT SYSTEM DIAGRAM
..... 11
8. TROUBLESHOOTING.......................12
9. SPECIAL FUNCTION ........................26
10. 4-WAY AIRFLOW SYSTEM............... 27
11. DISASSEMBLY PROCEDURE .......... 29
12. REMOTE CONTROLLER .................. 33
Indoor unit
[Model Name] [Service Ref.]
SLZ-KF09NA1
SLZ-KF12NA1
SLZ-KF15NA1
SLZ-KF18NA1
INDOOR UNIT
Model name
indication
SLZ-KF09NA1
SLZ-KF12NA1
SLZ-KF15NA1
SLZ-KF18NA1
WIRED REMOTE CONTROLLER
(Option)
PARTS CATALOG (TCB118)
SPLIT-SYSTEM HEAT PUMP
WIRELESS REMOTE
CONTROLLER
(Option)
No. TCH118
April 2023
MENU ON
OFF
RETURN SELECT
HOLD

3
2
TCH118
1REFERENCE MANUAL
OUTDOOR UNIT’S SERVICE MANUAL
Model Name Service Ref. Service Manual No. / Parts catalog No.
MXZ-2C20NA2
MXZ-2C20NA2
MXZ-3C24/30NA2
MXZ-4C36NA2
MXZ-5C42NA2
MXZ-2C20NAHZ2
MXZ-3C24/30NAHZ2
MXZ-2C20/24/30NA3
MXZ-4C36NA3
MXZ-5C42NA3
MXZ-2C20NAHZ3
MXZ-3C24/30NAHZ3
MXZ-2C20NA4
MXZ-3C24/30NA4
MXZ-4C36NA4
MXZ-5C42NA4
MXZ-2C20NAHZ4
MXZ-3C24/30NAHZ4
MXZ-2C20NA2 (-U1)
MXZ-2C20NA2 (-U4)
MXZ-3C24/30NA2 (-U1)
MXZ-4C36NA2 (-U1)
MXZ-5C42NA2 (-U1)
MXZ-2C20NAHZ2 (-U1)
MXZ-3C24/30NAHZ2 (-U1)
MXZ-2C20/24/30NA3 (-U1)
MXZ-4C36NA3 (-U1)
MXZ-5C42NA3 (-U1)
MXZ-2C20NAHZ3 (-U1)
MXZ-3C24/30NAHZ3 (-U1)
MXZ-2C20NA4-U1
MXZ-3C24/30NA4-U1
MXZ-4C36NA4-U1
MXZ-5C42NA4-U1
MXZ-2C20NAHZ4-U1
MXZ-3C24/30NAHZ4-U1
OBH702 / OBB702
MXZ-8C48/60NA2
MXZ-4C36NAHZ2
MXZ-5C42NAHZ2
MXZ-8C48NAHZ2
MXZ-8C48/60NA2 (-U1)
MXZ-4C36NAHZ2 (-U1)
MXZ-5C42NAHZ2 (-U1)
MXZ-8C48NAHZ2 (-U1)
OCH730 / OCB730
SUZ-KA09/12/15NA(H)2 SUZ-KA09/12/15NA(H)2 OCH699 / OCB699
SUZ-KA18NA(H)2 SUZ-KA18NA(H)2 OCH688 / OCB688
SUZ-KA09/12/15/18NAHZ SUZ-KA09/12/15/18NAHZ OCH709 / OCB709
PUMY-P36/42/60NKMU4
PUMY-HP36/42/48NKMU2
PUMY-P36/42/60NKMU4
PUMY-HP36/42/48NKMU2 OCH811 / OCB811
SAFETY PRECAUTION
2
Cautions for units utilizing refrigerant R410A
2-2. CAUTIONS RELATED TO NEW REFRIGERANT
2-1. ALWAYS OBSERVE FOR SAFETY
Before obtaining access to terminal, all supply circuits must be disconnected.

3
TCH118
2
Use new refrigerant pipes.
Make sure that the inside and outside of refrige-
rant piping is clean and it has no contamination
such as sulfur hazardous for use, oxides, dirt,
shaving particles, etc.
In addition, use pipes with specified thickness.
In case of using the existing pipes for R22, be careful with
the following:
· Be sure to clean the pipes and make sure that the insides
of the pipes are clean.
· Change flare nut to the one provided with this product.
Use a newly flared pipe.
· Avoid using thin pipes.
Charge refrigerant from liquid phase of gas
cylinder.
If the refrigerant is charged from gas phase, composition
change may occur in refrigerant and the efficiency will be
lowered.
Do not use refrigerant other than R410A.
If other refrigerant (R22, etc.) is used, chlorine in refrige-
rant can cause deterioration of refrigerant oil, etc.
Use a vacuum pump with a reverse flow check
valve.
Vacuum pump oil may flow back into refrigerant cycle and
that can cause deterioration of refrigerant oil, etc.
Use the following tools specifically designed for
use with R410A refrigerant.
The following tools are necessary to use R410A refrigerant.
Handle tools with care.
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of com-
pressor.
Do not use a charging cylinder.
If a charging cylinder is used, the composition of refrigera-
nt will change and the efficiency will be lowered.
Flare tool
Electronic refrigerant
charging scale
Vacuum pump adaptor
Size adjustment gauge
Gauge manifold
Torque wrench
Gas leak detector
Charge hose
Tools for R410A
Contamination inside refrigerant piping can cause deterio-
ration of refrigerant oil, etc.
· In case of reconnecting the refrigerant pipes after
detaching, make the flared part of pipe re-fabricated.
Ventilate the room if refrigerant leaks during
operation. If refrigerant comes into contact with
a flame, poisonous gases will be released.
Store the piping indoors, and keep both ends
of the piping sealed until just before brazing.
(Leave elbow joints, etc. in their packaging.)
If dirt, dust or moisture enters into refrigerant cycle, that can
cause deterioration of refrigerant oil or malfunction of compressor.
The refrigerant oil applied to flare and flange
connections must be ester oil, ether oil or
alkylbenzene oil in a small amount.
If large amount of mineral oil enters, that can cause deterio-
ration of refrigerant oil, etc.
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the
unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the
spec labels provided with our products.
We will not be held responsible for mechanical failure,
system malfunction, unit breakdown or accidents caused
by failure to follow the instructions.
Use the specified refrigerant only.
Preparation before the repair service.
• Prepare the proper tools.
• Prepare the proper protectors.
• Provide adequate ventilation.
• After stopping the operation of the air conditioner, turn off
the power-supply breaker.
• Discharge the condenser before the work involving the
electric parts.
Precautions during the repair service.
• Do not perform the work involving the electric parts
with wet hands.
• Do not pour water into the electric parts.
• Do not touch the refrigerant.
• Do not touch the hot or cold areas in the refrigerating cycle.
• When the repair or the inspection of the circuit needs to be
done without turning off the power, exercise great caution
not to touch the live parts.
• When opening or closing the valve below freezing
temperatures, refrigerant may spurt out from the gap
between the valve stem and the valve body, resulting in
injuries.

4 5
TCH118
[1] Warning for service
(1) Do not alter the unit.
(2) For installation and relocation work, follow the instructions in the Installation Manual and use tools and pipe
components specifically made for use with refrigerant specified in the outdoor unit installation manual.
(3) Ask a dealer or an authorized technician to install, relocate and repair the unit.
(4) This unit should be installed in rooms which exceed the floor space specified in outdoor unit installation manual.
Refer to outdoor unit installation manual.
(5) For appliances not accessible to the general public.
(6) Refrigerant pipes connection shall be accessible for maintenance purposes.
(7) If the air conditioner is installed in a small room or closed room, measures must be taken to prevent the refrig-
erant concentration in the room from exceeding the safety limit in the event of refrigerant leakage. Should the
refrigerant leak and cause the concentration limit to be exceeded, hazards due to lack of oxygen in the room may
result.
(8) Keep gas-burning appliances, electric heaters, and other fire sources (ignition sources) away from the location
where installation, repair, and other air conditioner work will be performed.
If refrigerant comes into contact with a flame, poisonous gases will be released.
(9) When installing or relocating, or servicing the air conditioner, use only the specified refrigerant written on out-
door unit to charge the refrigerant lines.
Do not mix it with any other refrigerant and do not allow air to remain in the lines.
If air is mixed with the refrigerant, then it can be the cause of abnormal high pressure in the refrigerant line, and
may result in an explosion and other hazards.
(10) After installation has been completed, check for refrigerant leaks. If refrigerant leaks into the room and comes
into contact with the flame of a heater or portable cooking range, poisonous gases will be released.
(11) Do not use low temperature solder alloy in case of brazing the refrigerant pipes.
(12) When performing brazing work, be sure to ventilate the room sufficiently. Make sure that there are no hazardous
or flammable materials nearby.
When performing the work in a closed room, small room, or similar location, make sure that there are no refriger-
ant leaks before performing the work.
If refrigerant leaks and accumulates, it may ignite or poisonous gases may be released.
(13) Do not install the unit in places where refrigerant may build-up or places with poor ventilation such as a semi-
basement or a sunken place in outdoor: Refrigerant is heavier than air, and inclined to fall away from the leak
source.
(14) Do not use means to accelerate the defrosting process or to clean, other than those recommended by the manu-
facturer.
(15) The appliance shall be stored in a room without continuously operating ignition sources (for example: open
flames, an operating gas appliance or an operating electric heater).
(16) Do not pierce or burn.
(17) Be aware that refrigerants may not contain an odour.
(18) Pipe-work shall be protected from physical damage.
(19) The installation of pipe-work shall be kept to a minimum.
(20) Compliance with national gas regulations shall be observed.
(21) Keep any required ventilation openings clear of obstruction.
(22) Servicing shall be performed only as recommended by the manufacturer.
(23) The appliance shall be stored in a well-ventilated area where the room size corresponds to the room area as
specified for operation.
(24) Maintenance, service and repair operations shall be performed by authorized technician with required qualifica-
tion.
[2] Cautions for service
(1) Perform service after recovering the refrigerant left in unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new refrigerant.
[3] Additional refrigerant charge
When charging directly from cylinder
(1) Check that cylinder for R410A available on the market is a syphon type.
(2) Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)

4 5
TCH118
[4] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
No. Tool name Specications
1. Gauge manifold · Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 5.3MPa·G [768.7 PSIG] or over.
2. Charge hose · Use pressure performance of 5.09MPa·G [738.2 PSIG] or over.
3. Electronic weighing scale ―
4. Gas leak detector · Use the detector for R410A.
5. Adaptor for reverse flow check · Attach on vacuum pump.
6. Refrigerant charge base ―
7. Refrigerant cylinder · Top of cylinder (R410A refrigerant)
· Cylinder with syphon
8. Refrigerant recovery equipment ―
Electronic weighing scale
Unit

6 7
TCH118
3PARTS NAMES AND FUNCTIONS
Auto Air Swing Vane
Disperses airflow up and
down and adjusts the angle
of airflow direction.
Grille
Filter
Removes dust and pollutants
from drawn in air.
Horizontal Air Outlet
Sets horizontal airflow automatically
during cooling or dehumidifying.
Air Intake
Draws in air from room.

6 7
TCH118
SPECIFICATIONS
4
250V 6.3A
MSBPC20M32 (Green label), MSBPC20M33 (Blue label): 12 V 300 Ω
TO OUTDOOR UNIT: 3P TO WIRED REMOTE CONTROLLER: 2P
INDOOR UNIT
Item
Service ref.
Fuse
Vane motor
Terminal block
(FUSE)
(MV)
(TB)
SLZ-KF09NA1 SLZ-KF12NA1 SLZ-KF15NA1 SLZ-KF18NA1
Specifications and rating conditions of main electric parts
Indoor unit service ref. SLZ-KF09NA1 SLZ-KF12NA1 SLZ-KF15NA1 SLZ-KF18NA1
Mode Cooling Heating Cooling Heating Cooling Heating Cooling Heating
Power supply (phase, cycle, voltage) Single phase 208/230 V, 60Hz
Electrical
data
Input [kW] 0.02 0.02 0.02 0.02 0.03 0.03 0.04 0.04
Current* [A] 0.20 0.15 0.24 0.19 0.32 0.27 0.43 0.38
Fan motor output* [kW] 0.05 0.05 0.05 0.05
Fan motor [F.L.A.] 0.29
Airow rate (Low/Medium/High)
[K/min] 6.5/7.5/8.5 6.5/8.0/9.5 7.0/9.0/11.5 8.5/12.0/13.5
[CFM] 230/265/300 230/280/335 245/315/405 300/420/475
Noise level (Low/Medium/High) [dB] 25/28/31 25/30/34 27/34/39 32/40/43
Dimensions
Width in (mm) UNIT: 22-7/16 (570) PANEL: 24-19/32 (625)
Depth in (mm) UNIT: 22-7/16 (570) PANEL: 24-19/32 (625)
Height in (mm) UNIT: 9-21/32 (245) PANEL: 13/32 (10)
Weight lb (kg) UNIT: 31 (14) PANEL: 5.3 (2.4)
NOTE : Test conditions are based on ISO 5151.
Indoor :
Outdoor :
Pipe length :
Nominal cooling condition
81˚FDB/66˚FWB (27˚CDB/19˚CWB)
95˚FDB (35˚CDB)
24-9/16 ft (7.5m)
Nominal heating condition
68˚FDB/59˚FWB (20˚CDB/15˚CWB)
45˚FDB/43˚FWB (7˚CDB/6˚CWB)
24-9/16 ft (7.5 m)
*Measured under rated operating frequency

9
8
TCH118
NOISE CRITERION CURVES
UNIT
4 ft
MICROPHONE
CEILING
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
High
Medium
31
SPL(dB)
28
LINE
<60Hz>
NOTCH
Low 25
SLZ-KF09NA1
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
High
Medium
39
SPL(dB)
34
LINE
<60Hz>
NOTCH
Low 27
SLZ-KF15NA1
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
High
Medium
34
SPL(dB)
30
LINE
<60Hz>
NOTCH
Low 25
SLZ-KF12NA1
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL, dB (0 dB = 0.0002 µbar)
BAND CENTER FREQUENCIES, Hz
High
Medium
43
SPL(dB)
40
LINE
<60Hz>
NOTCH
Low 32
SLZ-KF18NA1
NOTE: The sound level is measured in an anechoic room where
echoes are few, when compressor stops. The sound
may be bigger than the indicated level in actual use due
to surrounding echoes. The sound level can be higher
by about 2 dB than the indicated level during cooling
and heating operation.

9
TCH118
8
OUTLINES AND DIMENSIONS
5
Unit: inch (mm)
SLZ-KF09NA1 SLZ-KF12NA1 SLZ-KF15NA1 SLZ-KF18NA1

10 11
TCH118
WIRING DIAGRAM
6
SLZ-KF09NA1 SLZ-KF12NA1 SLZ-KF15NA1 SLZ-KF18NA1