Perfect Aire M2OF-18HFN1-M User manual

MULTI-ZONE OUTDOOR UNITS
SERVICE MANUAL
NON HH CONDENSERS: 3PAMSH18-MZO2,
3PAMSH27-MZO3, 3PAMSH36-MZO4, 3PAMSH48-MZO5
HH CONDENSERS: 3PAMS18-HH-MZO2, 3PAMS27-HH-MZO3,
3PAMS36-HH-MZO4, 3PAMS48-HH-MZO5

1
WARNING
Installation MUST conform with local building codes or, in the absence of local
codes, with the National Electrical Code NFPA70/ANSI C1-1993 or current edition
and Canadian Electrical Code Part1 CSA C.22.1.
The information contained in the manual is intended for use by a qualified service
technician familiar with safety procedures and equipped with the proper tools and
test instruments
Installation or repairs made by unqualified persons can result in hazards to you
and others.
Failure to carefully read and follow all instructions in this manual can result in
equipment malfunction, property damage, personal injury and/or death.
Model Numbers:
M3OF-27HFN1-M M4OF-36HFN1-M
M2OH-18HFN1-MM3OH-27HFN1-M
3PAMS48-HH-MZO5 3PAMS18-HH-MZO2
M2O
F-18HFN1-M
M5OF-48HFN1-M
M4OH-36HFN1-M
3PAMSH27-MZO3
3PAMSH18-MZO2
3PAMS27-HH-MZO3
3PAMS36-HH-MZO4
3PAMSH36-MZO4
3PAMSH48-MZO5

2
CONTENTS
1. Indoor Unit Combination ................................................................................................................... 5
2. Dimension Of Outdoor Unit............................................................................................................... 8
3. Refrigerant Cycle Diagram ...............................................................................................................10
4. Installation Details.............................................................................................................................14
4.1 Wrench torque sheet for installation ..............................................................................................14
4.2 Connecting the cables...................................................................................................................14
4.3 Pipe length and the elevation ........................................................................................................14
4.4 First-Time Installation....................................................................................................................14
4.5 Adding Refrigerant after Long-Term System Operation.................................................................16
4.6 Procedure when servicing the indoor unit refrigeration circuit........................................................16
4.7 Evacuation after servicing the outdoor unit refrigeration circuit......................................................17
5. Electronic Function...........................................................................................................................19
5.1 Abbreviation..................................................................................................................................19
5.2 Electric Control Working Environment...........................................................................................19
5.3 Main Protection .............................................................................................................................19
5.4 Control and Functions ...................................................................................................................21
6. Wiring Diagrams................................................................................................................................27
7. Troubleshooting................................................................................................................................54
7.1Safety.............................................................................................................................................54
7.2.............................................................................................................................Indoor Unit Error Display
55
7.3 Outdoor Unit Display .....................................................................................................................58
7.4 Diagnosis and Solution..................................................................................................................67
7.5 Trouble Criterion of Main Parts....................................................................................................126
8. Disassembly Instructions...............................................................................................................137
M2OF-18HFN1-M (WCA30 metal plate)......................................................................................137
3PAMSH18-MZO2 (WX430 metal plate)......................................................................................137

3
M2OH-18HFN1-M, M3OF-27HFN1-M, M3OH-27HFN1-M (WD30 metal plate) ..........................151
M4OF-36HFN1-M (WD30 metal plate) ........................................................................................159
M4OH-36HFN1-M, M5OF-48HFN1-M (WE30 metal plate)..........................................................166

4

5
1. Indoor Unit Combination
Multi DC Outdoor
Unit
Nominal
capacity
Suggested
Combination
Limit
M2OF-18HFN1-M
3PAMSH18-MZO2
5.2kW
6+6
None
6+9
6+12
9+9
9+12
12+12
M2OH-18HFN1-M
3PAMS18-HH-MZO2
5.2kW
6+6
None
6+9
6+12
6+18
9+9
9+12
12+12
Multi DC Outdoor
Unit
Nominal
capacity
Suggested Combination
Limit
Two units
Three units
M3OF-27HFN1-M
3PAMSH27-MZO3
7.8kW
6+12
6+6+6
6+12+12
None
6+18
6+6+9
6+12+18
9+9
6+6+12
9+9+9
9+12
6+6+18
9+9+12
9+18
6+9+9
9+9+18
12+12
6+9+12
9+12+12
12+18
6+9+18
12+12+12
18+18
M3OH-27HFN1-M
3PAMS27-HH-MZO3
7.8kW
6+12
6+6+6
6+9+18
None
6+18
6+6+9
6+12+12
9+9
6+6+12
9+9+9
9+12
6+6+18
9+9+12
9+18
6+6+24
9+9+18
9+24
6+9+9
9+12+12
12+12
6+9+12
12+12+12
12+18
12+24
18+18

6
Multi DC Outdoor Unit
Nominal capacity
Suggested Combination
Limit
Two units
Three units
Four units
M4OF-36HFN1-M
3PAMSH36-MZO4
10.5kW
6+18
6+6+12
9+9+12
6+6+6+6
6+9+9+18
None
6+24
6+6+18
9+9+18
6+6+6+9
6+9+9+24
9+18
6+6+24
9+9+24
6+6+6+12
6+9+12+12
9+24
6+9+12
9+12+12
6+6+6+18
6+9+12+18
12+12
6+9+18
9+12+18
6+6+6+24
6+12+12+12
12+18
6+9+24
9+12+24
6+6+9+9
6+12+12+18
12+24
6+12+12
9+18+18
6+6+9+12
9+9+9+9
18+18
6+12+18
12+12+12
6+6+9+18
9+9+9+12
18+24
6+12+24
12+12+18
6+6+9+24
9+9+9+18
24+24
6+18+18
12+12+24
6+6+12+12
9+9+12+12
6+18+24
12+18+18
6+6+12+18
9+9+12+18
9+9+9
6+6+12+24
9+12+12+12
6+9+9+9
12+12+12+12
6+9+9+12
M4OH-36HFN1-M
3PAMS36-HH-MZO4
10.5kW
6+18
6+6+12
9+9+9
6+6+6+6
6+9+9+12
None
6+24
6+6+18
9+9+12
6+6+6+9
6+9+9+18
6+30
6+6+24
9+9+18
6+6+6+12
6+9+9+24
9+18
6+6+30
9+9+24
6+6+6+18
6+9+12+12
9+24
6+9+12
9+9+30
6+6+6+24
6+9+12+18
9+30
6+9+18
9+12+12
6+6+6+30
6+12+12+12
12+12
6+9+24
9+12+18
6+6+9+9
6+12+12+18
12+18
6+9+30
9+12+24
6+6+9+12
9+9+9+9
12+24
6+12+12
9+18+18
6+6+9+18
9+9+9+12
12+30
6+12+18
12+12+12
6+6+9+24
9+9+9+18
18+18
6+12+24
12+12+18
6+6+12+12
9+9+12+12
18+24
6+12+30
12+12+24
6+6+12+18
9+9+12+18
18+30
6+18+18
12+18+18
6+6+12+24
9+12+12+12
24+24
6+18+24
6+9+9+9
12+12+12+12

7
Multi DC
Outdoor
Unit
Nominal
capacity
Suggested Combination
Limit
Two
units
Three units
Four units
Five units
M5OG-
42HFN1-
M-[X]
& M5OF-
48HFN1-M
&
3PAMS48-
HH-MZO5
&
3PAMSH
48-MZO5
14kW
9+24
6+6+24
9+12+18
6+6+6+18
6+9+18+30
6+6+6+6+9
6+6+12+12+12
None
9+30
6+6+30
9+12+24
6+6+6+24
6+12+12+12
6+6+6+6+12
6+6+12+12+18
9+36
6+6+36
9+12+30
6+6+6+30
6+12+12+18
6+6+6+6+18
6+6+12+12+24
12+24
6+9+24
9+12+36
6+6+6+36
6+12+12+24
6+6+6+6+24
6+6+12+18+18
12+30
6+9+30
9+18+18
6+6+9+18
6+12+12+30
6+6+6+6+30
6+9+9+9+9
12+36
6+9+36
9+18+24
6+6+9+24
6+12+18+18
6+6+6+6+36
6+9+9+9+12
18+18
6+12+18
9+18+30
6+6+9+30
6+12+18+24
6+6+6+9+9
6+9+9+9+18
18+24
6+12+24
9+18+36
6+6+9+36
9+9+9+9
6+6+6+9+12
6+9+9+9+24
18+30
6+12+30
9+24+24
6+6+12+12
9+9+9+12
6+6+6+9+18
6+9+9+9+30
18+36
6+12+36
9+24+30
6+6+12+18
9+9+9+18
6+6+6+9+24
6+9+9+12+12
24+30
6+18+18
12+12+12
6+6+12+24
9+9+9+24
6+6+6+9+30
6+9+9+12+18
24+36
6+18+24
12+12+18
6+6+12+30
9+9+9+30
6+6+6+9+36
6+9+9+12+24
30+30
6+18+30
12+12+24
6+6+12+36
9+9+9+36
6+6+6+12+12
6+9+9+18+18
6+18+36
12+12+30
6+6+18+18
9+9+12+12
6+6+6+12+18
6+9+12+12+12
6+24+24
12+12+36
6+6+18+24
9+9+12+18
6+6+6+12+24
6+9+12+12+18
6+24+30
12+18+18
6+6+18+30
9+9+12+24
6+6+6+12+30
6+9+12+12+24
9+9+18
12+18+24
6+6+24+24
9+9+12+30
6+6+6+18+18
6+12+12+12+12
9+9+24
12+18+30
6+9+9+12
9+9+18+18
6+6+6+18+24
6+12+12+12+18
9+9+30
12+24+24
6+9+9+18
9+9+18+24
6+6+9+9+9
9+9+9+9+9
9+9+36
18+18+18
6+9+9+24
9+12+12+12
6+6+9+9+12
9+9+9+9+12
9+12+12
18+18+24
6+9+9+30
9+12+12+18
6+6+9+9+18
9+9+9+9+18
6+9+9+36
9+12+12+24
6+6+9+9+24
9+9+9+9+24
6+9+12+12
9+12+12+30
6+6+9+9+30
9+9+9+12+12
6+9+12+18
9+12+18+18
6+6+9+12+12
9+9+9+12+18
6+9+12+24
9+12+18+24
6+6+9+12+18
9+9+9+12+24
6+9+12+30
12+12+12+12
6+6+9+12+24
9+9+12+12+12
6+9+12+36
12+12+12+18
6+6+9+12+30
9+9+12+12+18
6+9+18+18
12+12+12+24
6+6+9+18+18
9+12+12+12+12
6+9+18+24
12+12+18+18
6+6+9+18+24
12+12+12+12+12

8
2. Dimension Of Outdoor Unit
H
D
A
B
Model
Unit
W
D
H
W1
A
B
M2OF-18HFN1-M
mm
845
363
702
923
540
350
inch
33.3
14.3
27.6
36.0
21.3
13.8
3PAMSH18-MZO2
mm
890
342
673
990
663
354
inch
35.04
13.46
26.50
38.98
26.10
13.94
M2OH-18HFN1-M
M3OF-27HFN1-M
M3OH-27HFN1-M
3PAMS18-HH-MZO2
3PAMSH27-MZO3
3PAMS27-HH-MZO3
mm
946
410
810
1034
673
403
inch
37.2
16.5
31.9
40.6
26.5
15.9
M4OF-36HFN1-M
3PAMSH36-MZO4
mm
946
410
810
1034
673
403
inch
37.2
16.5
31.9
40.6
26.5
15.9

9
H
W
A
D
W1
B
Model
Unit
W
D
H
W1
A
B
M4OH-36HFN1-M
M5OF-48HFN1-M
3PAMS48-HH-MZO5
3PAMS36-HH-MZO4
3PAMSH48-MZO5
mm
952
415
1333
1060
634
404
inch
37.5
16.3
52.5
41.7
25.0
15.9

10
3. Refrigerant Cycle Diagram
3.1 Refrigeration circuit drawing of M2OF-18HFN1-M, 3PAMSH18-MZO2
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
CAPILLARY TUBE
EXV B
LIQUID VALVE B
GAS VALVE B
Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
3.2 Refrigeration circuit drawing of M2OH-18HFN1-M, 3PAMS18-HH-MZO2
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
CAPILLARY TUBE
EXV B
LIQUID VALVE B
GAS VALVE B
Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C

11
3.3 Refrigeration circuit drawing of M3OF-27HFN1-M, M3OH-27HFN1-M, 3PAMSH27-MZO3& 3PAMS27-HH-MZO3
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
CAPILLARY TUBE
EXV A
LIQUID VALVE A
GAS VALVE A
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
3.4 Refrigeration circuit drawing of M4OF-36HFN1-M, M4OH-36HFN1-M & 3PAMSH36-MZO4
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
CAPILLARY TUBE
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
EXV D
LIQUID VALVE D
GAS VALVE D
Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
T2B-D

12
3.5 Refrigeration circuit drawing of 3PAMS36-HH-MZO4
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
EXV D
LIQUID VALVE D
GAS VALVE D
Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
T2B-D
EXV F
Radiator for IPM
3.6 Refrigeration circuit drawing of M5OF-48HFN1-M
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
CAPILLARY TUBE
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
EXV D
LIQUID VALVE D
GAS VALVE D
EXV E
LIQUID VALVE E
GAS VALVE E Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
T2B-D
T2B-E

13
3.7 Refrigeration circuit drawing of 3PAMS48-HH-MZO5
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
CHECK VALVE
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
EXV D
LIQUID VALVE D
GAS VALVE D
EXV E
LIQUID VALVE E
GAS VALVE E Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
T2B-D
T2B-E
EXV F
Plate heat
exchanger EXV G Radiator for IPM
3.8 Refrigeration circuit drawing of 3PAMSH48-MZO5
LIQUID VALVE A
GAS VALVE A
HEAT
EXCHANGE
(EVAPORATOR) HEAT
EXCHANGE
(CONDENSER)
COOLING
HEATING
T2 Evaporator
temp. sensor
middle
T1 Room
temp. sensor
T3
Condenser
temp. sensor
T4 Ambient
temp. sensor
INDOOR OUTDOOR
EXV A
EXV B
LIQUID VALVE B
GAS VALVE B
EXV C
LIQUID VALVE C
GAS VALVE C
EXV D
LIQUID VALVE D
GAS VALVE D
EXV E
LIQUID VALVE E
GAS VALVE E Compressor
4-WAY VALVE
T5 Discharge
temp. sensor
Accumulator High pressure
switch
Low pressure
switch
T2B-A Evaporator
temp. sensor outlet
T2B-B
T2B-C
T2B-D
T2B-E
EXV F
Radiator for IPM

14
4. Installation Details
4.1 Wrench torque sheet for installation
Outside diameter
Torque
Additional tightening torque
mm
inch
N.cm
N.cm
Ф6.35
1/4
1500(153kgf.cm)
1600(163kgf.cm)
Ф9.52
3/8
2500(255kgf.cm)
2600(265kgf.cm)
Ф12.7
1/2
3500(357kgf.cm)
3600(367kgf.cm)
4.2 Connecting the cables
The power cord connection should be
selected according to the following
specifications sheet.
Unit
AWG
1 drive 2 type (18K outdoor unit)
14
1 drive 3 type (27K outdoor unit).
14
1 drive 4 type (36K outdoor unit)
12
1 drive 5 type (48K outdoor unit)
10
For indoor unit and outdoor unit connection
line, 16AWG is ok for all.
4.3 Pipe length and the elevation
Maximum piping length and height difference
1 drive 2
1 drive 3
1 drive 4
1 drive 5
Max. length for all
rooms (m)
40
(131ft)
60
(197ft)
80
(262ft)
80
(262ft)
Max. length for
one IU (m)
25 (82ft)
30 (98ft)
35
(115ft)
35
(115ft)
Max. height
difference between
IU and OU (m)
15
(49.2ft)
15
(49.2ft)
15
(49.2ft)
15
(49.2ft)
Max. height
difference between
IUs (m)
10 (33ft)
10 (33ft)
10 (33ft)
10 (33ft)
Additional refrigerant charge
Connective Pipe Length(m)
Additional refrigerant
Liquid Side
Ø 6.35 (1/4”)
Ø9.52 (3/8”)
Pre-charge pipe length
(ft/m)
(pre-charge pipe length
xN )
N/A
More than (pre-charge pipe
lengthxN) ft/m
(Total pipe
length - pre-
charge pipe
lengthxN)
x15g/m
(Total pipe length
-pre-charge pipe
lengthxN)
x30g/m
(Total pipe
length - pre-
charge pipe
lengthxN)
x0.16oZ/ft
(Total pipe length
-pre-charge pipe
lengthxN)
x0.32oZ/ft
Note:The standard pipe length is 7.5m
Caution:
●Refrigerant pipe diameter is different
according to indoor unit to be connected.
When using the extension pipe, refer to the
tables below.
●When refrigerant pipe diameter is different
from that of the outdoor unit connector (18K
indoor unit) an additional adapter is required.
Indoor unit
Extension pipe diameter
(mm/inch)
Model
Pipe diameter
(mm/inch)
9K
Liquid
6.35(1/4)
Liquid
6.35(1/4)
Gas
9.52(3/8)
Gas
9.52(3/8)
12K 18K
Liquid
6.35(1/4)
Liquid
6.35(1/4)
Gas
12.7(1/2)
Gas
12.7(1/2)
24K
Liquid
9.52 (3/8)
Liquid
9.52 (3/8)
Gas
15.9(5/8)
Gas
15.9(5/8)
Outdoor unit union diameter (mm/inch)
1 drive 2
Liquid
6.35(1/4) *2
Gas
9.52(3/8) *2
1 drive 3
Liquid
6.35(1/4) *3
Gas
9.52(3/8) *3
1 drive 4
Liquid
6.35(1/4) *4
Gas
9.52(3/8) *3
12.7(1/2) *1
1 drive 5
Liquid
6.35(1/4) *5
Gas
9.52(3/8) *3
12.7(1/2) *2
4.4 First-Time Installation
Air and moisture in the refrigerant system cause
the following problems:
●Increases in system pressure
●Increases in operating current
●Decreases in cooling and heating efficiency
●Blocks in capillary piping caused by moisture
in the refrigerant circuit freezing
●Corrosion of parts in the refrigerant system
caused by water
The indoor units and the pipes between
indoor and outdoor units must be tested for
leakages and evacuated to remove gas and
moisture from the system.
Gas leak check with soap water:
Apply soap water or a liquid neutral
detergent on the connections with a soft brush to
check for leakage in the pipe connecting points. If
bubbles emerge, the pipes are leaking.

15
1. Air Purging Using the Vacuum Pump
1. Completely tighten the flare nuts on the
indoor and outdoor units. Confirm that both
the2-way and 3-way valves are set to the
closed position.
2. Connect the charge hose with the push pin of
the Handle Lo to the 3-way valve gas service
port.
3. Connect the charge hose of the Handle Hi to
the vacuum pump.
4. Fully open the Handle Lo of the manifold
valve.
5. Turn on the vacuum pump to begin
evacuation.
6. Conduct a 30-minute evacuation. Check
whether the compound meter indicates -
0.1Mpa(14.5Psi). If the meter does not
indicate -0.1Mpa(14.5Psi) after 30 minutes
has elapsed, continue evacuation for 20 more
minutes. If the pressure does not reach -
0.1Mpa(14.5Psi) after 50 minutes has
elapsed, check if there are any leaks.
Fully close the Handle Lo valve of the manifold
valve and turn off the vacuum pump. After 5
minutes, confirm that the gauge needle is not
moving.
7. Turn the flare nut on the 3-way valve45°
counterclockwise for 6-7 seconds. Once gas
begins to come out, tighten the flare nut.
Make sure the pressure display on the
pressure indicator is higher than atmospheric
pressure. Then remove the charge hose from
the 3-way valve.
8. Fully open the 2-wayand 3-way valves and
securely tighten the cap on the 3-way valve.
2. Adding refrigerant if the pipe length
exceeds chargeless pipe length
Procedure:
1) Connect the charge hose to the charging cylinder
and open the 2-way and 3-way valves.
With the charge hose you disconnected from the
vacuum pump, connect it to the valve at the
bottom of the cylinder.
If the refrigerant is R410A, place the cylinder
bottom-up to ensure liquid charging is possible.
2). Purge the air from the charge hose.
Open the valve at the bottom of the cylinder and
press the check valve on the charge set (be
careful of the liquid refrigerant).
3) Place the charging cylinder onto the electronic
scale and record the weight.
4) Turn on the air conditioner in cooling mode.
5) Open the valves (Low side) on the charge set.
Charge the system with liquid refrigerant.
6).When the electronic scale displays the proper
weight (refer to the table), disconnect the charge
hose from the 3-way valve’s service port
immediately and turn off the air conditioner before
disconnecting the hose.
7). Mount the valve stem caps and the service port
Use a torque wrench to tighten the service port
cap to a torque of 18N.m(13.27 ft·lbs).
Be sure to check for gas leaks.

16
4.5 Adding Refrigerant after Long-Term
System Operation
Procedure
1) Connect the charge hose to the 3-way service
port and open the 2-way and 3-way valve.
Connect the charge hose to the valve at the
bottom of the cylinder. If the refrigerant is R410A,
place the cylinder bottom-up to ensure liquid
charge.
2). Purge the air from the charge hose.
Open the valve at the bottom of the cylinder and
press the check valve on the charge set to purge
the air (be careful of the liquid refrigerant).
3) Place the charging cylinder onto the electronic
scale and record the weight.
4) Turn on the air conditioner in cooling mode.
5) Open the valves (Low side)on the charge set and
charge the system with liquid refrigerant.
6).When the electronic scale displays the proper
weight (refer to the gauge and the pressure of the
low side), disconnect the charge hose from the 3-
way valve’s service port immediately and turn off
the air conditioner before disconnecting the hose.
7). Mount the valve stem caps and the service port.
Use torque wrench to tighten the service port cap
to a torque of 18N.m(13.27 ft·lbs).
Be sure to check for gas leaks.
4.6 Procedure when servicing the indoor
unit refrigeration circuit.
1. Collecting the refrigerant into the outdoor
unit
Procedure
1). Confirm that both the 2-way and 3-way valves
are set to the opened position
Remove the valve stem caps and confirm that the
valve stems are in the opened position.
Be sure to use a hexagonal wrench to operate the
valve stems.
2). Connect the charge hose with the push pin of
handle lo to the 3-way valves gas service port.
3).Air purging of the charge hose.
Open the handle Lo valve of the manifold valve
slightly to purge air from the charge hose for 5
seconds and then close it quickly.
4). Set t e 2-way valve to the close position.
5). Operate the air conditioner at the cooling cycle
and stop it when the gauge indicates 0.1MPa.
6). Set the 3-way valve to the closed position
immediately
Do this quickly so that the gauge ends up indicating
0.3 to 0.5Mpa.
Disconnect the charge set, and tighten the 2-way
and 3-way valve’s stem nuts.
Use a torque wrench to tighten the 3-way valves
service port cap to a torque of 18N.m.
Be sure to check for gas leakage.
2.Air purging with vacuum pump

17
1) Completely tighten the flare nuts of the indoor
and outdoor units, confirm that both the 2-way
and 3-way valves are set to the closed
position.
2) Connect the charge hose with the push pin of
handle lo to the 3-way valves gas service port.
3) Connect the charge hose of handle hi
connection to the vacuum pump.
4) Fully open the handle Lo of the manifold
valve.
5) Operate the vacuum pump to evacuate.
6) Make evacuation for 30 minutes and check
whether the compound meter indicates -
0.1Mpa. If the meter does not indicate -
0.1Mpa after pumping 30 minutes, it should
be pumped 20 minutes more. If the pressure
can’t achieve -0.1Mpa after pumping 50
minutes, please check if there are some
leakage points.
Fully close the handle Lo valve of the manifold
valve and stop the operation of the vacuum pump.
Confirm that the gauge needle does not move
(approximately 5 minutes after turning off the
vacuum pump).
7) Turn the flare nut of the 3-way valves about
45°counterclockwise for 6 or 7seconds after
the gas
coming out, then tighten the flare nut again. Make
sure the pressure display in the pressure
indicator is a little higher than the atmosphere
pressure. Then remove the charge hose from the
3 way valve.
8) Fully open the 2 way valve and 3 way valve
and securely tighten the cap of the 3 way
valve.
4.7 Evacuation after servicing the outdoor
unit refrigeration circuit
1. Evacuation of the complete refrigeration
circuit, Indoor and outdoor unit.
Procedure:
1). Confirm that both the 2-way and 3-way valves
are set to the opened position.
2). Connect the vacuum pump to 3-way valve’s
service port.
3). Evacuation for approximately one hour.
Confirm that the compound meter indicates -
0.1Mpa (500 Microns / 29.9 in,hg).
4). Close the valve (Low side) on the charge set,
turn off the vacuum pump, and confirm that the
gauge needle does not move (approximately 5
minutes after turning off the vacuum pump).
5). Disconnect the charge hose from the vacuum
pump.
2. Refrigerant charging
Procedure:
1). Connect the charge hose to the charging
cylinder, open the 2-way valve and the 3-way
valve.
Connect the charge hose which you disconnected

18
from the vacuum pump to the valve at the bottom
of the cylinder. If the refrigerant is R410A, make
the cylinder bottom up to ensure liquid charge.
2). Purge the air from the charge hose
Open the valve at the bottom of the cylinder and
press the check valve on the charge set to purge
the air (be careful of the liquid refrigerant).
3) Put the charging cylinder onto the electronic
scale and record the weight.
4). Open the valves (Low side) on the charge set
and charge the system with liquid refrigerant
If the system cannot be charge with the specified
amount of refrigerant, or can be charged with a
little at a time (approximately 150g each time) ,
operating the air conditioner in the cooling cycle;
however, one time is not sufficient, wait
approximately 1 minute and then repeat the
procedure.
5).When the electronic scale displays the proper
weight, disconnect the charge hose from the 3-
way valve’s service port immediately
If the system has been charged with liquid
refrigerant while operating the air conditioner, turn
off the air conditioner before disconnecting the
hose.
6). Mounted the valve stem caps and the service
port. Use torque wrench to tighten the service
port cap to a torque of 18N·m (13.27 ft·lbs).
Always leak check after servicing the refrigerant
system.
For M3OF-27HFN1-M/M4OF-36HFN1-M/M5OF-
48HFN1-M/M2OH-18HFN1-M/M3OH-27HFN1-M/
M4OH-36HFN1-M/ 3PAMS48-HH-MZO5
There are one low-pressure centralized valve and
one high-pressure centralized valve, it will be
more time saving when vacuum and recycle
refrigerant. But refer to the previous instruction
when vacuum and recycle refrigerant.

19
5. Electronic Function
5.1 Abbreviation
T1: Indoor ambient temperature
T2: Middle indoor heat exchanger coil
temperature
T2B: Indoor heat exchanger exhaust coil
temperature (located on the outdoor unit)
T3: Outdoor heat exchanger pipe temperature
T4: Outdoor ambient temperature
T5: Compressor discharge temperature
5.2 Electric Control Working Environment.
5.2.1 Input voltage: 230V.
5.2.2 Input power frequency: 60Hz.
5.2.3 Indoor fan standard working amp.: <1A
5.2.4 Outdoor fan standard working amp.: <1.5A.
5.2.5 Four-way valve standard amp.: <1A.
5.3 Main Protection
5.3.1 Compressor Restart Delay
---- The compressor takes 1 minute to start up the
first time. Further restarts take 3 minutes.
5.3.2 Temperature Protection of Compressor
Discharge.
When the discharge temperature of the
compressor rises, the running frequency is limited
according to the following rules:
----If 105℃(221 ℉)≦T5<110℃(230 ℉), maintain
the current frequency.
----If the temperature increase and T5≧110℃
(230 ℉), decrease the frequency to a lower level
every 2 minutes till to F1.
---If T5≧115℃(239 ℉) for 10 seconds, the
compressor stops and then restart until T5<90℃
(194 ℉).
5.3.3 Fan Speed Malfunction
---- If outdoor fan speed is lower than 100RPM or
higher than 2400RPM for 60 seconds or more,
the unit stops and LED displays failure code.
5.3.4 Inverter Module Protection.
---- The inverter protection module ensures that
faults related to current, voltage, or temperature
does not damage the inverter.
If these protections are triggered, the A/C unit
stops and the LED displays the failure code.
The unit restarts 3 minutes after the protection
mechanism has turned off.
5.3.5 Low Voltage Protection
VOLTAGE
No limit
VOLT_LTM_FREQ1_ADD
VOLT_LTM_FREQ2_ADD
Note: If low voltage protection triggers and
voltage is not restored to normal within 3
minutes, the protection remains active even
after a machine restart.
5.3.6 Compressor Current Limit Protection
The temperature interval for the current limit is
the same as the range of the T4 frequency limit.
Cooling mode: