LG LP-F8081ZL Service Manual ▷ View online
–32–
Gas side
Liquid side
Indoor unit
Outdoor unit
Closed
3-way
valve
Closed
3-way
valve
7.1 Air purging
Required tools: hexagonal wrench, adjustable wrench, torque wrench, and gas leak detector.
The additional gas for air purging has been charged in the outdoor unit.
However, if the flare connections have not been done correctly and there gas leaks, a gas cylinder and the charge
set will be needed.
The air in the indoor unit and in the piping must be purged. If air remains in the refrigeration pipes, it will affect the
compressor, reduce cooling capacity, and can lead to a malfunction.
The additional gas for air purging has been charged in the outdoor unit.
However, if the flare connections have not been done correctly and there gas leaks, a gas cylinder and the charge
set will be needed.
The air in the indoor unit and in the piping must be purged. If air remains in the refrigeration pipes, it will affect the
compressor, reduce cooling capacity, and can lead to a malfunction.
• Procedure
¤
Recheck the piping connections.
¤Ł
Open the valve stem of the 3-way(liquid side) valve
counterclockwise approximately 90°, wait 10
seconds, and then set it to closed position.
- Be sure to use a hexagonal wrench to operate the
counterclockwise approximately 90°, wait 10
seconds, and then set it to closed position.
- Be sure to use a hexagonal wrench to operate the
valve stem.
¤Ø
Check for gas leakage.
-Check the flare connections for gas leakage.
-Check the flare connections for gas leakage.
¤Œ
Purge the air from the system.
- Set the 3-way(liquid side) valve to the open
- Set the 3-way(liquid side) valve to the open
position and remove the cap from the 3-way(gas
side) valve's service port.
side) valve's service port.
- Using the hexagonal wrench to press the valve
core pin, discharge for three seconds and then
wait for one minute. Repeat this three times.
wait for one minute. Repeat this three times.
¤º
Use torque wrench to tighten the service port nut.
¤
Set the 3-way (gas side) valve to the back seat.
¤
Mount the valve stem nuts to the 3-way (liquid
side)valve and 3-way (gas side) valves.
side)valve and 3-way (gas side) valves.
¤
Check for gas leakage.
• At this time, especially check for gas leakage from
the 3-way (liquid side) valve and 3-way (gas side)
valve's stem nuts, and from the service port nut.
valve's stem nuts, and from the service port nut.
Caution
If gas leakage is discovered in step
¤
¤Ø
Ø
above,
take the following measures:
If the gas leaks stop when the piping connections are
tightened further, continue working from step
If the gas leaks stop when the piping connections are
tightened further, continue working from step
¤Œ
.
If the gas leaks do not stop when the connections are
retightened, repair the location of the leak, discharge
all of the gas through the service port, and then
recharge with the specified amount of gas from a gas
cylinder.
retightened, repair the location of the leak, discharge
all of the gas through the service port, and then
recharge with the specified amount of gas from a gas
cylinder.
Service port nut.
Be sure, using a torque wrench to tighten the service port nut (after using the service port), so that it prevents the
gas leakage from the refrigeration cycle.
gas leakage from the refrigeration cycle.
7.2 Pump down
• Procedure
¤
Confirm that both 3-way(liquid side) and 3-
way(gas side) valves are set to the open position.
way(gas side) valves are set to the open position.
• Remove the valve stem caps and confirm that the
valve stems are in the raised position.
• Be sure to use a hexagonal wrench to operate
the valve stems.
¤Ł
Operate the unit for 10 to 15 minutes.
¤Ø
Stop operation and wait for 3 minutes, then
connect the charge set to the service port of the
3-way (gas side) valve.
- Connect the charge hose with the push pin to the
connect the charge set to the service port of the
3-way (gas side) valve.
- Connect the charge hose with the push pin to the
service port.
¤Œ
Air purging of the charge hose.
• Open the low-pressure valve on the charge
• Open the low-pressure valve on the charge
equipment slightly to purge air from the charge
hose.
hose.
¤º
Set the 3-way(liquid side) valve to the closed
position.
position.
¤
Operate the air conditioner at the cooling cycle
and stop it when the gauge indicates 1 kg/cm
and stop it when the gauge indicates 1 kg/cm
2
g
¤
Immediately set the 3-way(gas side) valve to the
closed position.
- Do this quickly so that the gauge ends up
closed position.
- Do this quickly so that the gauge ends up
indicating 3 to 5kg/cm
2
g.
¤
Disconnect the charge set, and mount the
3-way(liquid side) and 3-way(gas side) valve's
stem nuts and the service port nut.
3-way(liquid side) and 3-way(gas side) valve's
stem nuts and the service port nut.
- Use torque wrench to tighten the service port nut.
- Be sure to check gas leakage.
- Be sure to check gas leakage.
Lo
CLOSE
CLOSE
Purge the air
Gas side
Liquid side
Indoor unit
Outdoor unit
Closed
Open
3-Way
valve
3-Way
valve
–33–
1) Re-airpurging
(Re-installation)
• Procedure
¤
Confirm that both the 3-way (liquid side) valve
and the 3-way(gas side) valve are set to the
closed position.
and the 3-way(gas side) valve are set to the
closed position.
¤Ł
Connect the charge set and a gas cylinder to the
service port of the 3-way(gas side) valve.
• Leave the valve on the gas cylinder closed.
• Leave the valve on the gas cylinder closed.
¤Ø
Air purging.
• Open the valves on the gas cylinder and the
charge set. Purge the air by loosening the flare
nut on the 3-way(liquid side) valve approximately
45° for 3 seconds then closing it for 1 minute;
repeat 3 times.
nut on the 3-way(liquid side) valve approximately
45° for 3 seconds then closing it for 1 minute;
repeat 3 times.
• After purging the air, use a torque wrench to
tighten the flare nut on liquid side valve.
¤Œ
Check gas leakage.
• Check the flare connections for gas leakage.
• Check the flare connections for gas leakage.
¤º
Discharge the refrigerant.
• Close the valve on the gas cylinder and
• Close the valve on the gas cylinder and
discharge the refrigerant until the gauge indicates
3 to 5kg/cm
3 to 5kg/cm
2
g
¤
Disconnect the charge set and the gas cylinder,
and set the 3-way(liquid side) and 3-way(gas side)
valves to the open position.
• Be sure to use a hexagonal wrench to operate
and set the 3-way(liquid side) and 3-way(gas side)
valves to the open position.
• Be sure to use a hexagonal wrench to operate
the valve stems.
¤
Mount the valve stem nuts and the service port nut.
• Use torque wrench to tighten the service port nut.
• Be sure to check gas leakage.
CLOSE
OPEN
R22
Gas side
Gas cylinder
Liquid side
Indoor unit
Outdoor unit
Closed
3-Way
valve
Closed
3-Way
valve
–34–
2) Balance refrigerant of the 3-way(liquid side), 3-way(gas side) valves
(Gas leakage)
• Procedure
¤
Confirm that both the liquid side and gas side valves are set to the back seat.
¤Ł
Connect the charge set to the 3-way(gas side) valve's port.
• Leave the valve on the charge set closed.
• Connect the charge hose with the push pin to the service port.
• Connect the charge hose with the push pin to the service port.
¤Ø
Open the valve (Lo side) on the charge set and discharge the refrigerant until the gauge indicates 0 kg/cm
2
g.
- If there is no air in the refrigerant cycle (the pressure when the air conditioner is not running is higher than 1
kg/cm
2
g), discharge the refrigerant until the gauge indicates 0.5 to 1 kg/cm
2
g. In case of this, it will not be
necessary to apply an evacuation.
- Discharge the refrigerant gradually; if it is discharged too suddenly, the refrigeration oil will also be discharged.
CLOSE
OPEN
Gas side
Liquid side
Indoor unit
Outdoor unit
Open
Open
3-Way
valve
3-Way
valve
–35–
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