Fujitsu ASUH18LMAS User manual

AIR CONDITIONER
Wall mounted type
SERVICE MANUAL
INDOOR
ASUH18LMAS ASUH24LMAS
OUTDOOR
AOUH18LMAS1
AOUH24LMAS1
SR_AS052EF_03
2021.11.17

Notices:
• Product specifications and design are subject to change without notice for future improvement.
• For further details, please check with our authorized dealer.
Trademarks
FGLair™ is trademark of Fujitsu General Limited in the United States, other countries or both.
Google Play™ is trademark of Google Inc.
App Store® is a service mark of Apple Inc., registered in the U.S. and other countries.
Copyright © 2021 Fujitsu General Limited. All rights reserved.

CONTENTS
1. GENERAL INFORMATION
2. TECHNICAL DATA AND PARTS LIST
3. TROUBLESHOOTING
4. CONTROL AND FUNCTIONS
5. FILED WORKING

1. GENERAL INFORMATION
2021.11.01
SR_CH01_AS052EF_01

CONTENTS
1. GENERAL INFORMATION
1. Specifications..............................................................................................01-1
1-1. Indoor unit ......................................................................................................................01-1
1-2. Outdoor unit....................................................................................................................01-3
2. Dimensions..................................................................................................01-4
2-1. Indoor unit ......................................................................................................................01-4
2-2. Outdoor unit....................................................................................................................01-8

1. Specifications
1-1. Indoor unit
Type Wall mounted
Inverter heat pump
Model name ASUH18LMAS ASUH24LMAS
Power supply 208/230 V ~ 60 Hz
Power supply intake Outdoor unit
Available voltage range 187—253 V
Capacity
Cooling
Rated k→ 5.28 6.45
Btu/h 18,000 22,000
Min.—Max. k→ 2.05—5.86 2.67—8.00
Btu/h 7,000—20,000 9,100—27,300
Heating
Rated k→ 6.33 7.39
Btu/h 21,600 25,200
Min.—Max. k→ 2.34—8.50 2.40—10.84
Btu/h 8,000—29,000 8,200—37,000
Heating
(17°F)*1
Rated k→ 3.99 4.60
Btu/h 13,600 15,700
Max. k→ 6.95 8.41
Btu/h 23,700 28,700
Input power
Cooling Rated
k→
1.38 1.76
Min.—Max. 0.45—1.86 0.43—2.63
Heating Rated 1.58 1.87
Min.—Max. 0.55—2.82 0.52—3.53
Heating
(17°F)*1
Rated 1.28 1.51
Max. 0.41—3.06 0.39—3.60
Current Cooling Rated A 6.2 7.8
Heating 7.0 8.3
EER Cooling k→/k→ 3.80 3.66
Btu/h→ 13.0 12.5
COP Heating k→/k→ 4.00 3.95
Btu/h→ 13.6 13.5
SEER Cooling Btu/h→ 21.1 22.5
HSPF Heating Btu/h→ 12.5 12.0
Power factor Cooling %96.8 98.1
Heating 98.1 98.0
Moisture removal pints/h (L/h) 4.0 (1.9) 6.3 (3.0)
Maximum operating current*2Cooling A13.4 15.4
Heating 13.9 15.9
Fan
Airflow rate
Cooling
HIGH
CFM (m3/h)
577 (980) 647 (1,100)
MED 489 (830) 530 (900)
LO→ 377 (640) 436 (740)
QUIET 300 (510) 371 (630)
Heating
HIGH 589 (1,000) 730 (1,240)
MED 500 (850) 530 (900)
LO→ 377 (640) 436 (740)
QUIET 300 (510) 371 (630)
Type × Q'ty Crossflow fan × 1
Motor output → 59 78
Sound pressure level*3
Cooling
HIGH
dB (A)
46 46
MED 41 42
LO→ 35 37
QUIET 30 33
Heating
HIGH 46 48
MED 41 38
LO→ 35 34
QUIET 30 30
Heat exchanger type
Dimensions (H × → × D) in (mm)
Main 1: 8-1/4 × 31-5/16 × 1-1/16
(210 × 796 × 26.6)
Main 2: 4-15/16 × 31-5/16 × 1-1/16
(126 × 796 × 26.6)
Sub 1: 3-5/16 × 31-5/16 × 1/2
(84 × 796 × 13.3)
18-3/16 × 35-6/16 × 1-1/16
(462 × 898 × 26.6)
Fin pitch FPI (mm)
Main 1: 21 (1.2)
Main 2: 21 (1.2)
Sub 1: 18 (1.4)
21 (1.2)
Rows × Stages
Main 1: 2 × 10
Main 2: 2 × 6
Sub 1: 1 × 4
2 × 22
Pipe type Copper
Fin type Aluminum
Enclosure
Material Polystyrene
Color →hite
Approximate color of Munsell N 9.25/
Dimensions
(H × → × D)
Net
in (mm)
11 × 38-9/16 × 9-7/16
(280 × 980 × 240)
13-6/16 × 45-4/16 × 11
(340 × 1,150 × 280)
Gross 12-11/16 × 42-7/16 × 13-5/8
(322 × 1,078 × 346)
15-15/16 × 50 × 17-11/16
(405 × 1,270 × 450)
→eight Net lb (kg) 29 (13.0) 36 (16.5)
Gross 36 (16.5) 49 (22.0)
Connection pipe Size Liquid in (mm) Ø3/8 (Ø9.52) Gas Ø5/8 (Ø15.88)
Method Flare
Drain hose
Material PP+HDPE
Tip diameter in (mm) Ø17/32 (Ø13.8) (I.D.),
Ø19/32 to 21/32 (Ø15.0 to 16.8) (O.D.)
1-1. Indoor unit - (01-1) - 1. Specifications
GENERAL INFORMATION GENERAL INFORMATION

Type Wall mounted
Inverter heat pump
Model name ASUH18LMAS ASUH24LMAS
Operation range Cooling °F (°C) 64 to 90 (18 to 32) %RH 80 or less
Heating °F (°C) 86 (30) or less
Remote controller type →ireless (→ired, Mobile app*4 [FGLair™] [option])
NOTES:
• Specifications are based on the following conditions:
– Cooling: Indoor temperature of 80°FDB (26.67°CDB) /67°F→B (19.44°C→B), and outdoor temperature of 95°FDB (35°CDB) / 75°F→B (23.9°C→B).
– Heating: Indoor temperature of 70°FDB (21.11°CDB) /59°F→B (15.56°C→B), and outdoor temperature of 47°FDB (8.33°CDB) /43°F→B (6.11°C→B).
– *1: Heating (17°F): Indoor temperature of 70°FDB (21.11°CDB) /60°F→B (15.56°C→B), and outdoor temperature of 17°FDB (-8.33°CDB) /15°F→B (-9.44°C→B).
– Pipe length: 25 ft (7.5 m), Height difference: 0 ft (0 m). (Between outdoor unit and indoor unit.)
• Protective function might work when using it outside the operation range.
• *2: Maximum current is maximum value when operated within the operation range.
• *3: Sound pressure level:
– Measured values in manufacturer’s anechoic chamber.
– Because of the surrounding sound environment, the sound levels measured in actual installation conditions might be higher than the specified values here.
• *4: Available on Google Play™ store or on App Store®. Optional →LAN adapter is also required. For details, refer to the setting manual.
1-1. Indoor unit - (01-2) - 1. Specifications
GENERAL INFORMATION GENERAL INFORMATION

1-2. Outdoor unit
Type Inverter heat pump
Model name AOUH18LMAS1 AOUH24LMAS1
Power supply 208/230 V ~ 60 Hz
Power supply intake Outdoor unit
Available voltage range 187—253 V
Starting current A 7.0 8.3
Fan
Airflow rate Cooling CFM (m3/h) 1,683 (2,860) 1,936 (3,290)
Heating 1,742 (2,960) 2,187 (3,715)
Type × Q'ty Propeller fan × 1
Motor output → 100
Sound pressure level *1 Cooling dB (A) 49 52
Heating 50 54
Heat exchanger type
Dimensions
(H × → × D) in (mm) Main 1: 29-3/4 × 35-5/8 × 11/16 (756 × 905 × 18.19) Main 2: 29-3/4 × 35-5/8 × 11/16 (756 × 905 × 18.19)
Fin pitch FPI Main 1: 18 (1.45)
Main 2: 18 (1.45)
Rows × Stages Main 1: 1 × 36
Main 2: 1 × 36
Pipe type Copper
Fin type Type (Material) Aluminum
Surface treatment Blue fin
Compressor Type DC twin rotary
Motor output → 1,360
Refrigerant
Type R410A
Charge lb oz 3 lb 15 oz 4 lb 10 oz
g 1,800 2,100
Refrigerant oil Type POE (RB68)
Amount in3 (cm3)48.8 (800)
Enclosure
Material Steel sheet
Color Beige
Approximate color of Munsell 10↔R 7.5/1.0
Dimensions
(H × → × D)
Net in (mm) 31 × 37 × 12-5/8 (788 × 940 × 320)
Gross 38-1/16 × 40-7/16 × 17-1/2 (966 × 1,027 × 445)
→eight Net lb (kg) 117 (53)
Gross 134 (61)
Connection pipe
Size Liquid in (mm) Ø3/8 (Ø9.52)
Gas Ø5/8 (Ø15.88)
Method Flare
Pre-charge length
ft (m)
49 (15) 66 (20)
Max. length 164 (50)
Max. height difference 98 (30)
Drain hose
Material LDPE
Tip diameter in (mm) Ø1/2 (Ø13.0) (I.D.),
Ø5/8 to 11/16 (Ø16.0 to 16.7) (O.D.)
Operation range Cooling °F (°C) 14 to 115 (-10 to 46)
Heating 5 to 75 (-15 to 24)
NOTES:
• Specifications are based on the following conditions:
– Cooling: Indoor temperature of 80 °FDB (26.67 °CDB) / 67 °F→B (19.44 °C→B), and outdoor temperature of 95 °FDB (35 °CDB) / 75 °F→B (23.9 °C→B).
– Heating: Indoor temperature of 70 °FDB (21.11 °CDB) / 59 °F→B (15 °C→B), and outdoor temperature of 47 °FDB (8.33 °CDB) / 43 °F→B (6.11 °C→B).
– Pipe length: 25 ft (7.5 m), Height difference: 0 ft (0 m). (Between outdoor unit and indoor unit.)
• Protective function might work when using it outside the operation range.
• *1: Sound pressure level
– Measured values in manufacturer’s anechoic chamber.
– Because of the surrounding sound environment, the sound levels measured in actual installation conditions might be higher than the specified values here.
1-2. Outdoor unit - (01-3) - 1. Specifications
GENERAL INFORMATION GENERAL INFORMATION

2. Dimensions
2-1. Indoor unit
¢Model: ASUH18LMAS
Unit: in (mm)
38-9/16 (980) 9-7/16 (240)
11 (280)
for pipe inlet
Ø3-1/8 (80)
1-15/16 (50) 1-15/16 (50)
2-3/8 (60) 16-15/16 (430)
2-1/16 (52)
Outline of indoor unit
for pipe inlet
Ø3-1/8 (80)
2-13/16
(72)
16-7/16 (418)
3-9/16
(91)
15-3/4 (400) 3-9/16
(90)
16-1/4 (413)3-1/16
(77)
16-7/16 (417)
19 (482)
20-1/16 (510)
2-1. Indoor unit - (01-4) - 2. Dimensions
GENERAL INFORMATION GENERAL INFORMATION

Installation space requirement
Provide sufficient installation space for product safety.
CAUTION
Do not place any other electrical products or household belongings under the product. Condensa-
tion dripping from the product might get them wet, and may cause damage or malfunction to the
property.
Unit: in (mm)
60 (1,500) or more
71 (1,800) or more
2 50) or more
2 (40) or more
5 (117) or more
71 or more
3 (70) or more
7 (160) or more
Wall hook bracket
Outline of the indoor unit
2-1. Indoor unit - (01-5) - 2. Dimensions
GENERAL INFORMATION GENERAL INFORMATION

¢Model: ASUH24LMAS
Unit: in (mm)
Outline of unit
20-1/2 (520) 3-9/16 (90)
13/16 (20)
2-1/2 (64)
18-7/8 (479)2-6/16 (61)
4-1/4
(108)19-6/8 (502)
20-1/2 (520)
1-15/16 (50)
1-15/16
(50)
7/16 (11)
13-6/16 (340)
ø80
ø80
13-6/16
(340)
11 (280)
10/16
(16)
45-1/4 (1,150)
19 (483)
21-7/16 (544)
22-1/16 (560)
45-1/4 (1,150)
2-1. Indoor unit - (01-6) - 2. Dimensions
GENERAL INFORMATION GENERAL INFORMATION

Installation space requirement
Provide sufficient installation space for product safety.
CAUTION
Do not place any other electrical products or household belongings under the product. Conden-
sation dripping from the product might get them wet, and may cause damage or malfunction to
the property.
2-1/2 (63)
or more
3-8/1 (80)
or more
1-15/16 (50)
or more
1-15/16 (50)
or more
2-3/4 (70)
or more
Outline of unit
5-1/2 (140)
or more
59-1/16 (1,500) or more
70-7/8 (1,800) or more
Unit: in (mm)
2-1. Indoor unit - (01-7) - 2. Dimensions
GENERAL INFORMATION GENERAL INFORMATION

2-2. Outdoor unit
¢Models: AOUH18LMAS1 and AOUH24LMAS1
Unit: in (mm)
Top view
Bottom view
Side view
Front view
37 (940)
12-5/8 (320)
1-9/16 (40) 9/16 (14)
1
(25)
1 (25) 7/8 (23)
2-16/16 (75)
2-3/16 (55)
2-1/2
(63)
9/16
(15)
15-3/8 (390)
3-1/2
(89)
31 (788)
7/8 (23)
1/2 (13)
4-3/4 (120)
5-1/16 (129)
3-3/8 (85)
1-15/16 (50)
1-15/16 (50)
5/8
(16)
1-7/8
(48)
1-15/16 (50)
2-5/16 (59)
5-3/16 (131)
3-3/4 (95)
3-3/4 (96)
5-1/2
(140)
2-Ф7/8 (22)
Cable port 2-Ф7/8 (22)
Cable port
2-Ф1/8 (28)
Cable port 2-Ф1/8 (28)
Cable port
Pipe port
Pipe port
25-9/16 (650)
13-7/8 (352)
3-way valve
(Gas)
3-way valve
(Liquid)
1-1/4 (48)
Liquid
A
Detail A
5-5/8
(143)
5-13/16
(147)
2-3/16 (55)
Liquid
1-9/16
(40)
12-5/8 (320)
10-7/16
(265)
13-15/16 (354)
10-1/2 (266)
Liquid
11-5/8 (296)
Gas
2-1/2 (64)
Gas
Rear view
Detail B
B
Detail C
C
2-2. Outdoor unit - (01-8) - 2. Dimensions
GENERAL INFORMATION GENERAL INFORMATION

2. TECHNICAL DATA AND PARTS LIST
2021.11.17
SR_CH02_AS052EF_04

CONTENTS
2. TECHNICAL DATA AND PARTS LIST
1. Precautions..................................................................................................02-1
2. Indoor unit parts list....................................................................................02-2
2-1. Model: ASUH18LMAS ....................................................................................................02-2
2-2. Model: ASUH24LMAS ....................................................................................................02-6
3. Outdoor unit parts list...............................................................................02-10
3-1. Models: AOUH18LMAS1 and AOUH24LMAS1............................................................02-10
4. Accessories ...............................................................................................02-14
4-1. Indoor unit ....................................................................................................................02-14
4-2. Outdoor unit..................................................................................................................02-16
5. Refrigerant system diagrams...................................................................02-17
5-1. Models: AOUH18LMAS1 and AOUH24LMAS1............................................................02-17
6. Wiring diagrams ........................................................................................02-18
6-1. Indoor unit ....................................................................................................................02-18
6-2. Outdoor unit..................................................................................................................02-19
7. PC board diagrams ...................................................................................02-20
7-1. Models: ASUH18LMAS and ASUH24LMAS.................................................................02-20
7-2. Models: AOUH18LMAS1 and AOUH24LMAS1............................................................02-21

1. Precautions
→hen you start servicing, pay attention to the following points. For detailed precautions, refer to the
installation manual of the products.
CAUTION
• Service personnel
– Any person who is involved with working on or breaking into a refrigerant circuit should hold a
current valid certificate from an industry-accredited assessment authority, which authorizes
their competence to handle refrigerants safely in accordance with an industry recognized as-
sessment specification.
– Servicing shall only be performed as recommended by the equipment manufacturer. Mainte-
nance and repair requiring the assistance of other skilled personnel shall be carried out under
the supervision of the person competent in the use of flammable refrigerants.
– Servicing shall be performed only as recommended by the manufacturer.
• →ork
– →ork in confined spaces shall be avoided.
– The area around the workspace shall be sectioned off.
– Electric shock may occur. After turning off the power, always wait 5 minutes before touching
electrical components.
– Do not touch the fins of the heat exchanger. Touching the heat exchanger fins could result in
damage to the fins or personal injury such as skin rupture.
– Do not place any other electrical products or household belongings under the product.
– Condensation dripping from the product might get them wet, and may cause damage or mal-
function to the property.
• Service parts information and design are subject to change without notice for product improve-
ment.
• For the latest information of the service parts, refer to our Service Portal.
https://fujitsu-general.force.com/portal/
• Precise figure of the service parts listed in this manual may differ from the actual service parts.
- (02-1) - 1. Precautions
TECHNICAL DATA AND PARTS LIST TECHNICAL DATA AND PARTS LIST

2. Indoor unit parts list
2-1. Model: ASUH18LMAS
¢Exterior parts
1
2
2
7
13
14
15
18
17
20 19
a
b
c
15
16
8
5
9
10
9
3
6
4
11
12
2-1. Model: ASUH18LMAS - (02-2) - 2. Indoor unit parts list
TECHNICAL DATA AND PARTS LIST TECHNICAL DATA AND PARTS LIST

Item no. Part no. Part name Service part
1 9388158013 Bracket panel ♦
2 9387476002 Screw cap ♦
3 9313951047 Conduit holder ♦
4 9383729027 →ire cover assy B ♦
5 9387597035 →ire cover assy ♦
6 9383765056 →LAN adapter holder assy ♦
7 9387479010 Louver assy (Up/Down) ♦
8 9323342033 Under cover R ♦
9 9332911008 Electric filter holder ♦
10 9317250009 Air cleaning filter assy ♦
11 9332438895 →ireless remote controller ♦
12 9318912005 Remote controller holder ♦
13 9384977007 Front panel total assy ♦
14 9387756210 Intake grille assy ♦
15 9323340008 Air filter ♦
16 9333719009 Grille clamper L ♦
17 9333704005 Grille clamper R ♦
18 9323341036 Under cover L ♦
19 9333608006 Bush ♦
20 9383730030 Louver spring ♦
a— Front panel —
b— Panel cover —
c— Front panel B —
2-1. Model: ASUH18LMAS - (02-3) - 2. Indoor unit parts list
TECHNICAL DATA AND PARTS LIST TECHNICAL DATA AND PARTS LIST

¢Chassis
59
61
61
61
51
50
72
62
63
d
f
e
71
66
68
67
65
64
a
54
53
b
55
56
58
57
c
70
69
59
60
52
2-1. Model: ASUH18LMAS - (02-4) - 2. Indoor unit parts list
TECHNICAL DATA AND PARTS LIST TECHNICAL DATA AND PARTS LIST