DOWNLOAD LG LT-D3680CL / LT-D3680HL / LT-D3682HL / LT-D4820CL / LT-D4820HL / LT-D4822HL / LT-D4880CL / LT-D4880HL Service Manual ↓ Size: 1.77 MB | Pages: 55 in PDF or view online for FREE

–18–

• There should not be any heat source or steam

near the unit. 

• There should not be any obstacles to prevent the

air circulation.

• A place where air circulation in the room will be

good. 

• A place where drainage can be easily obtained.
• A place where noise prevention is taken into con-

sideration.

• Do not install the unit near the door way.
• Ensure the spaces indicated by arrows from the

wall, ceiling, or other obstacles.

• The indoor unit must keep the maintenance

space.

• If an awning is built over the unit to prevent direct

sunlight or rain exposure, be careful that heat
radiation from the condenser is not restricted. 

• There should not be any animals or plants which

could be affected by hot air discharged. 

• Ensure the spaces indicated by arrows from the

wall, ceiling, fence or other obstacles.

Indoor unit

Outdoor unit

B

A

More than
30cm

More than 70cm

More than 50cm

More than

More than
30cm

More than
30cm

Unit:cm

Ceiling

Ceiling Board

Ceiling Board

30 or more

Abo

ve

 250

400 or less

100 

or more

50 or 

more

50 or 

more

30 or less

Floor

CAPACITY

36K Btu/h

5/8"

3/8"

7.5

50

48K Btu/h

3/4"

3/8"

7.5

50

GAS

LIQUID

5

30

50

5

30

60

Elevation B (m)

Length A (m)

* Additional

refrigerant

(g/m)

Pipe Size

Rated

Rated

Max.

Max.

• Rated performance for refrigerant line length of: 7.5m
• If 48K Model is installed at a distance of 15m, 450g of refrigerant should be added

(15-7.5) x 60g

–27–

Air conditioner
unit

Ceiling

board

Decorative panel

Decorative 
panel

Fit the insulator (this part) and 
be careful for cool air leakage

Good example

Air

Cool air leakage

(no good)

Bad example

Ceiling

board

Air conditioner unit

Feed water

Drain Pump

Drain pan

Flexible drain hose
(accessory)

Main 
drain pipe

Glue the joint

Drain
port

Drain hose connection
Use the clip (accessory)

Maintenance
drain port

Upward
routing
not allowed

1/50~1/100

MAX 700mm

Piping material: Polyvinyl chloride pipe VP-25
and pipe fittings

The air conditioner uses a drain pump to drain water.
Use the following procedure to test the drain pump operation:

• Connect the main drain pipe to the exterior

and leave it provisionally until the test comes
to an end.

• Feed water to the flexible drain hose and

check the piping for leakage.

• Be sure to check the drain pump for normal

operating and noise when electrical wiring is
complete.

• When the test is complete, connect the flexi-

ble drain hose to the drain port on the indoor
unit.

Heat insulation material: Polyethylene foam with
thickness more than 8 mm.

Install certainly the decorative panel.
Cool air leakage causes sweating.  

Water drops fall.

• Drain piping must have down-slope (1/50 to 1/100):

be sure not to provide up-and-down slope to prevent
reversal flow.

• During drain piping connection, be careful not to

exert extra force on the drain port on the indoor unit.

• The outside diameter of the drain connection on the

indoor unit is 32mm.

• Be sure to execute heat insulation on the drain piping.

–28–

1. Use the heat insulation material for the refrigerant piping which has an excellent heat-resistance (over 120°C).

2. Precautions in high humidity circumstance:

This air conditioner has been tested according to the
"KS Standard Conditions with Mist" and confirmed
that there is not any default. However, if it is operated
for a long time in high humid atmosphere (dew point
temperature: more than 23°C), water drops are liable
to fall. In this case, add heat insulation material
according to the following procedure:

• Heat insulation material to be prepared... Adiabatic
glass wool with thickness 10 to 20mm.
• Stick glass wool on all air conditioners that are located in ceiling atmosphere.
• In addition to the normal heat insulation (thickness: more than 8mm) for refrigerant piping (gas piping: thick pip-

ing) and drain piping, add further 10mm to 30mm thickness material.

Indoor unit

Thermal insulator 
(accessory)

Fastening band 
(accessory)

Refrigerant piping

•If you want to connect an additional drain hose, the
end of the drain-outlet should keep distance from
the ground. (Do not dip it into water, and fix it on the
wall to avoid swinging in the wind.) 

Plastic Band

Trap is required to prevent water from entering 
into electrical parts.

Seal a small opening
around the pipings
with gum type sealer.

Drain hose

Taping

Pipings

Connecting
cable

Power supply
cord

–29–

Seal a small opening 
around the pipings 
with gum type sealer.

Trap

• The initial power supply must provide at least 90% of the rated voltage.

Otherwise, the air conditioner should not be operated.

For test run, carry out the cooling operation firstly even during heating season. If heating operation
is carried out firstly, it leads to the trouble of compressor. Then attention must be paid.
Carry out the test run more than 5 minutes without fail.
(Test run will be cancelled 18 minutes later automatically)

• The test run is started by pressing the room temperature checking button and down timer button for 3 sec-

onds at the same time.

• To cancel the test run, press any button.

• After completing work, be sure to measure and record trial run properties, and store measured data, etc.
• Measuring items are room temperature, outside temperature, suction temperature, blow out temperature,

wind velocity, wind volume, voltage, current, presence of abnormal vibration and noise, operating pressure,
piping temperature, compressive pressure.

• As to the structure and appearance, check following items.

Is the circulation of air adequate?
Is the draining smooth?
Is the heat insulation complete

(refrigerant and drain piping)?

Is there any leakage of refrigerant?

Is the remote controller switch operated?
Is there any faulty wiring?
Are not terminal screws loosened?

M4......118N.cm{12kgf.cm}   M5......196N.cm{20kgf.cm}
M6......245N.cm{25kgf.cm}   M8......588N.cm{60kgf.cm}