LG LT-E1860FJ/FH User manual

Ceiling Cassette
Air Conditioner
SERVICE MANUAL
MODELS: LT-E1860FJ/FH
LT-E2460FJ/FH
LT-D2860RJ/RH/FJ/FH
LT-D3681RJ/RH/FJ/FH
LT-D4881RJ/RH/FJ/FH

Contents
Model Identification .................................................................................................................3
Functions .................................................................................................................................4
Product Specifications (Cooling & Heating)..........................................................................6
Dimensions ..............................................................................................................................9
Refrigeration Cycle Diagram ................................................................................................13
Wiring Diagram ......................................................................................................................14
Operation Details ...................................................................................................................18
Installation of Indoor, Outdoor Unit .....................................................................................21
Cycle........................................................................................................................................36
Cycle Troubleshooting Guide ...............................................................................................39
Electronic Parts Troubleshooting Guide .............................................................................40
Electronic Control Device .....................................................................................................43
Schematic Diagram ...............................................................................................................44
Exploded View and Replacement Parts List .......................................................................45
–2–

Model Identification
–3–
LT-D3681RJ
8 : 380~415V /50Hz / 3ø6 : 220~240V /50Hz / 1ø
18: 18,000 Btu/hr
24: 24,000 Btu/hr
28: 28,000 Btu/hr
36: 36,000 Btu/hr
48: 48,000 Btu/hr
Cooling/Heating Capacity
H: Non-Plasma filter Model (R-407C)
J: Plasma filter Model (R-407C)
R : Heat Pump(New Ref.) F: Cooling Only (New ref.)
Development Sequence
Options
Electric Standard (Volts / Freq. / Phase)
LT: LG Ceiling Cassette Type Air Conditioner
Type of Air Conditioner
D : D Chassis E : E Chassis
Chassis Type
Model Type

Functions
–4–
Indoor Unit
Operation ON/OFF by Remote controller
Sensing the Room Temperature
Room temperature control
Starting Current Control
Time Delay Safety Control
Indoor Fan Speed Control
Soft Dry Operation Mode
Airflow Direction Control
Auto Operation(Auto Change Over)
Deice (defrost) control (Heating)
Auto Restart
Hot-start Control (Heating) •The indoor fan stops until the evaporator piping tempera-
ture will be reached at 28°C.
Compact and light design •To install a unit is very convenient because of smaller size
than textile. ( 600 x 600 )
Low noise •The most advanced low-noise design.
•The adoption of turbo fan and round type heat exchanger
give the quietest operation.
Long life filter •Long life wrinkle(type) and washable and anti-bacteria filter
is adopted.
Plasma Air Purifying Filter(RJ/FJ Only)
High head Drain pump •Built-in drain pump automatically drains water.
•A standard drain-head height of up to 700mm is possible.
High-Ceiling corresponding Function •According to the height of ceiling, the RPM of indoor fan
motor is selected to increase air reaching distance.
Central Control(Optional) •
It is operating individually or totally by central control function.
Group Control(Optional Wiring) •
Each controller can control 16 units and 8 controllers can be
connected.
• It operates maximum 16 units by only one wired remote con-
troller and each unit starts sequentially to prevent overcurrent.
•Room temperature sensor. (Thermistor)
•
Maintains the room temperature in accordance with the Setting Temp.
•Indoor fan is delayed for 5 seconds at the starting.
•Restarting is inhibited for approx. 3 minutes.
•Jet, High, Med, Low
•Intermittent operation of fan at low speed.
•The louver can be set at swing up and down automatically.
•Although the air-conditioner is turned off by a power failure, it is restarted automati-
cally previous operation mode after power supply.
•The setting temperature and desired operation mode are auto-
matically set by fuzzy logic.
•Both the indoor and outdoor fan stops during defrosting.
•Hot start after defrost ends.

–5–
Remote Controller
Operation ON/OFF
Operation Mode Selection
Fan Speed Selection
Room Temperature Display
Temperature Setting
Setting the Timer
Weekly Program
(Cooling
model only) (Heating
model only)
(Low) (Med) (High)
Cooling Operation Mode ( )
Heating Operation Mode ( ) Auto Operation Mode ( )
Soft Dry Operation Mode ( )
Fan Operation Mode
HI JET AUTOMEDLO
Program Holiday
SET/CLR
MinHour
Week
Timer CancelTimer Cancel
: High:39°C ↔LOW:11°C
: Fan Operates without cooling & heating
Cooling Heating
Down to 18°C
Up to 30°CDown to 16°C Up to 30°C

–6–
Product Specifications (Cooling & Heating)
Model
1, 220-240, 50 1, 220-240, 50
4,536(5,274) 5,872(6,892)
18,000 23,300
--
--
2,050 2,800
--
9.2 12.5
--
2.57 2.46
--
13 20
50 56
1.9 3
OO
OO
44
OO
OO
OO
OO
OO
44
OO
OO
OO
OO
OO
OO
Optional Optional
OO
O / X O / X
1,650 1,400
570 x 570 x 269 840 x 840 x 288
670 x 670 x 30 950 x 950 x 30
870 x 655 x 320 870 x 800 x 320
19 19
61 60
14 : 3*2.5 14 : 3*2.5
18 : 6*0.75 18 : 6*0.75
1/4 (6.35mm) 1/4 (6.35mm)
1/2 (12.7mm) 5/8 (15.88mm)
Ø25/32 Ø25/32
LT-E1860FJ
LT-E1860FH LT-E2460FJ LT-E2460FH
Power Supply ø, V, Hz
Capacity Cooling kcal/h(W)
Btu/h
Heating kcal/h(W)
Btu/h
Input Cooling W
Heating W
Running Current Cooling A
Heating A
E. E. R W/W
C.O.P W/W
Air Circulation Indoor m3/min
Outdoor m3/min
Moisture Removal / h
Air-Flow Direction Control
Heating Operation Mode
Fan Speeds (steps)
Auto Operation (Changeover)
Forced Operation
Jet Cool
Soft Dry Operation
Timer Delay Safety Function
Feature Air Deflection (Way)
Self Diagnosis
Hot start
Auto Restart
Air refresh (Hole)
High Ceiling
Group Control (Optional wiring)
Central Control
Wired remote controller (with weekly Program)
Plasma A/Cleaner
Refrigerant(R-407C) Charge g
Dimensions Indoor mm
(W x D x H) Panel mm
Outdoor mm
Net Weight Indoor kg
Outdoor kg
Main Power Cord AWG#:P*mm2
Connection Cable AWG#:P*mm2
Service Valve Liquid (inch)
Gas (inch)
Drain Hose(I.D/O.D) mm

–7–
Model
1, 220-240, 50 1, 220-240, 50
7,056(8,206) 7,056(8,206)
2,800 2,800
7,056(8,206) -
2,800 -
2,800 2,900
2,580 -
12.8 13
11.9 -
2.93 2.83
3.18 -
20 20
56 56
22
OO
OX
44
OO
OO
OO
OO
OO
44
OO
OX
OO
OO
OO
OO
Optional Optional
OO
O / X O / X
1,850 1,950
840 x 840 x 288 840 x 840 x 288
950 x 950 x 30 950 x 950 x 30
870 x 800 x 320 870 x 800 x 320
32 32
81 81
14 : 3*2.5 14 : 3*2.5
18 : 6*0.75 18 : 4*0.75
1/4 (6.35mm) 1/4 (6.35mm)
5/8 (15.88mm) 5/8 (15.88mm)
Ø25/32 Ø25/32
LT-D2860RJ
LT-D2860RH LT-D2860FJ LT-D2860FH
Power Supply ø, V, Hz
Capacity Cooling kcal/h(W)
Btu/h
Heating kcal/h(W)
Btu/h
Input Cooling W
Heating W
Running Current Cooling A
Heating A
E. E. R W/W
C.O.P W/W
Air Circulation Indoor m3/min
Outdoor m3/min
Moisture Removal / h
Air-Flow Direction Control
Heating Operation Mode
Fan Speeds (steps)
Auto Operation (Changeover)
Forced Operation
Jet Cool
Soft Dry Operation
Timer Delay Safety Function
Feature Air Deflection (Way)
Self Diagnosis
Hot start
Auto Restart
Air refresh (Hole)
High Ceiling
Group Control (Optional wiring)
Central Control
Wired remote controller (with weekly Program)
Plasma A/Cleaner
Refrigerant(R-407C) Charge g
Dimensions Indoor mm
(W x D x H) Panel mm
Outdoor mm
Net Weight Indoor kg
Outdoor kg
Main Power Cord AWG#:P*mm2
Connection Cable AWG#:P*mm2
Service Valve Liquid (inch)
Gas (inch)
Drain Hose(I.D/O.D) mm

–8–
Model
3, 380-415, 50 3, 380-415, 50 3, 380-415, 50 3, 380-415, 50
9,073(10,550) 9,073(10,550) 12,096(14,065) 12,096(14,065)
36,000 36,000 48,000 48,000
9,073(10,500) - 12,096(14,065) -
36,000 - 48,000 -
4,400 4,400 4,800 4,800
3,700 - 4,600 -
7.2 7.2 8.0 8.0
6.1 - 7.6 -
2.4 2.4 2.93 2.93
2.85 - 3.05 -
25 25 30 30
68 68 105 105
1.9 1.9 3.0 3.0
OOOO
OXOX
4444
OOOO
OOOO
OOOO
OOOO
OOOO
4444
OOOO
OXOX
OOOO
OOOO
OOOO
OOOO
Optional Optional Optional Optional
OOOO
O / X O / X O / X X
2,480 2,450 4,600 4,600
840 x 840 x 288 840 x 840 x 288 840 x 840 x 288 840 x 840 x 288
950 x 950 x 30 950 x 950 x 30 950 x 950 x 30 950 x 950 x 30
870 x 800 x 320 870 x 800 x 320 900 x 370 x 1225 900 x 370 x 1225
32 32 32 32
81 81 95 95
14 : 3*2.5 14 : 3*2.5 14 : 3*2.5 14 : 3*2.5
18 : 6*0.75 18 : 4*0.75 18 : 6*0.75 18 : 4*0.75
1/4 (6.35mm) 1/4 (6.35mm) 3/8 (9.52mm) 3/8 (9.52mm)
5/8 (15.88mm) 5/8 (15.88mm) 3/4 (19.05mm) 3/4 (19.05mm)
Ø25/32 Ø25/32 Ø25/32 Ø25/32
LT-D3681RJ
LT-D3681RH LT-D3681FJ LT-D3681FH LT-D4881RJ LT-D4881RH LT-D4881FJ LT-D4881FH
Power Supply ø, V, Hz
Capacity Cooling kcal/h(W)
Btu/h
Heating kcal/h(W)
Btu/h
Input Cooling W
Heating W
Running Current Cooling A
Heating A
E. E. R W/W
C.O.P W/W
Air Circulation Indoor m3/min
Outdoor m3/min
Moisture Removal / h
Air-Flow Direction Control
Heating Operation Mode
Fan Speeds (steps)
Auto Operation (Changeover)
Forced Operation
Jet Cool
Soft Dry Operation
Timer Delay Safety Function
Feature Air Deflection (Way)
Self Diagnosis
Hot start
Auto Restart
Air refresh (Hole)
High Ceiling
Group Control (Optional wiring)
Central Control
Wired remote controller (with weekly Program)
Plasma A/Cleaner
Refrigerant(R-407C) Charge g
Dimensions Indoor mm
(W x D x H) Panel mm
Outdoor mm
Net Weight Indoor kg
Outdoor kg
Main Power Cord AWG#:P*mm2
Connection Cable AWG#:P*mm2
Service Valve Liquid (inch)
Gas (inch)
Drain Hose(I.D/O.D) mm

–9–
Dimensions
269
67055
570
269
190.5
160
52
90 90
120.4 30 521
670
570
450
40
110 110
670
670
CLOSE OPEN OPEN CLOSE
(1) Indoor Unit
• Model : LT-E1860FJ/FH, LT-E2460FJ/FH

–10–
290
950
950
950
950
290
210.5
180
52
140
40
110
30
90 90
110
55
840
785
840
678
• Model : LT-D2860RJ/RH, LT-D2860FJ/FH
LT-D3681RJ/RH, LT-D3681FJ/FH
LT-D4881RJ/RH, LT-D4881FJ/FH