DOWNLOAD LG LS-C186V L2 / LS-H186V L2 Service Manual ↓ Size: 2.39 MB | Pages: 63 in PDF or view online for FREE

1. Pour a glass of water on the evaporator.

2. Ensure the water flows through the drain hose of the

indoor unit without any leakage and goes out the
drain exit.

1. The drain hose should point downward for easy drain

flow.

2. Do not make drain piping like the following.

Downward slope

Do not raise

Accumulated
drain water

Tip of drain hose 
dipped in water

Air

Waving

Water
leakage

Water
leakage

Ditch

Less than 
50mm gap

Water
leakage

• If you want to connect an additional drain hose, the

end of the drain outlet should be routed above the
ground. Secure the drain hose appropriately.

1. Tape the piping, drain hose and connecting cable

from down to up.

2. Secure the tapped piping along the exterior wall

using saddle or equivalent.

1. Tape the piping and connecting cable from down to

up.

2. Secure the taped piping along the exterior wall. Form

a trap to prevent water entering the room.

3. Fix the piping onto the wall by saddle or equivalent.

Taping

Drain hose

Pipings

Connecting cable

Trap is required to prevent water
from entering electrical parts.

Seal small openings
around pipings with a
gum type sealer.

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

Trap

Trap

The air and moisture remaining in the refrigerant system have undesirable effects as indicated below.

1. Pressure in the system rises.
2. Operating current rises.
3. Cooling(or heating) efficiency drops.
4. Moisture in the refrigerant circuit may freeze and block capillary tubing.
5. Water may lead to corrosion of parts in the refrigeration system.
Therefore, after evacuating the system, take a leak test for the piping and tubing between the indoor and outdoor unit.

1. Preparation

• Check that each tube(both liquid and gas side tubes) between the indoor and outdoor units have been properly connected and

all wiring for the test run has been completed. Remove the service valve caps from both the gas and the liquid side on the out-
door unit. Note that both the liquid and the gas side service valves on the outdoor unit are kept closed at this stage.

2. Leak test

• Connect the manifold valve(with pressure gauges) and dry nitrogen gas cylinder to this service port with charge hoses.

• Pressurize the system to no more than 150 P.S.I.G. with dry nitrogen gas and close the cylinder valve when the gauge

reading reached 150 P.S.I.G. Next, test for leaks with liquid soap.

1. Do a leak test of all joints of the tubing(both indoor and outdoor) and both gas and liquid side service valves.

Bubbles indicate a leak. Be sure to wipe off the soap with a clean cloth.

2. After the system is found to be free of leaks, relieve the nitrogen pressure by loosening the charge hose connector at

the nitrogen cylinder. When the system pressure is reduced to normal, disconnect the hose from the cylinder.

Lo

Hi

Indoor unit

Outdoor unit

Manifold valve

Charge hose

Nitrogen gas
cylinder(in vertical
standing position)

Pressure 

gauge

1. Remove the caps from the 2-way and 3-way valves.
2. Remove the service-port cap from the 3-way valve.
3. To open the 2-way valve turn the valve stem counterclock-

wise approximately 90°, wait for about 2~3 sec, and close it.

4. Apply a soap water or a liquid neutral detergent on the

indoor unit connection or outdoor unit connections by a soft
brush to check for leakage of the connecting points of the
piping.

5. If bubbles come out, the pipes have leakage

1. Connect the charge hose end described in the preceding

steps to the vacuum pump to evacuate the tubing and
indoor unit.
Confirm the "Lo" knob of the manifold valve is open.
Then, run the vacuum pump.
The operation time for evacuation varies with tubing
length and capacity of the pump. The following table
shows the time required for evacuation.

2. When the desired vacuum is reached, close the "Lo"

knob of the manifold valve and stop the vacuum pump.

1. With a service valve wrench, turn the valve stem of liquid

side valve counter-clockwise to fully open the valve.

2. Turn the valve stem of gas side valve counter-clockwise

to fully open the valve.

3. Loosen the charge hose connected to the gas side ser-

vice port slightly to release the pressure, then remove
the hose.

4. Replace the flare nut and its bonnet on the gas side ser-

vice port and fasten the flare nut securely with an
adjustable wrench. This process is very important to pre-
vent leakage from the system.

5. Replace the valve caps at both gas and liquid side ser-

vice valves and fasten them tight.

This completes air purging with a vacuum pump. 
The air conditioner is now ready to test run.

Gas side

Liquid side

Cap

Hexagonal wrench

2-way valve

(Open)

3-way valve

(Close)

Required time for evacuation when 30 gal/h vacuum

pump is used

10 min. or more

15 min. or more

If tubing length is less

than 10m (33 ft)

If tubing length is longer

than 10m (33 ft)

Indoor unit

Outdoor unit

Lo

Hi

Manifold valve

Vacuum pump

Pressure 
gauge

Open

Close