LG LP-8091PC, Service Manual

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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.
• Procedure
① Recheck the piping connections.
② 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
valve stem.
③
Check for gas leakage.
-Check the flare connections for gas leakage.
④
Purge the air from the system.
- 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.
- Using the hexagonal wrench to press the valve
core pin, discharge for three seconds and then
wait for one minute. Repeat this three times.
⑤ Use torque wrench to tighten the service port nut.
⑥
Set the 3-way (gas side) valve to the back seat.
⑦
Mount the valve stem nuts to the 3-way (liquid
side)valve and 3-way (gas side) valves.
⑧
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.
Caution
If gas leakage is discovered in step ③ ③ above,
take the following measures:
If the gas leaks stop when the piping connections are
tightened further, continue working from step
④
.
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.
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.