7
Air Purging Method
5
◇ The connected piping between indoor and outdoor units contains air inside. Air-purge is the process to remove this
air.
Existence of non-condensable gas, such as oxygen or nitrogen gas, inside piping line causes increase of discharge
pressure, heating of compressor, degradation of the performance of air conditioner and refrigerant noise, etc.
Therefore, air-purge is an essentially required process.
◇ Air purging by refrigerant of outdoor unit (in case length of piping is of 10m or less)
▶Connect piping lines of indoor and outdoor units. (Service valves of gas and liquid are both closed.)
▶Loosely fasten nuts (④) for connection of gas service valve (so that the nuts can be unfastened by hand).
▶Remove nut caps (⑧,⑨) and port cap (⑩) of service
valve.
▶Using a hexagonal wrench, rotate spindle (⑦) of liquid
service valve by 90°in anticlockwise direction. Hold the
spindle in position for 8 ~ 10 seconds. Rotate it again by
90°in clockwise direction to close. Then, completely
fasten nuts (④) for connection of gas service valve.
▶Press side of the service port (⑥) of gas pipe service
valve 2 or 3 times (for 3 seconds per time) to completely
remove air from inside the valve.
▶Completely open gas and liquid service valve spindles
(⑤, ⑦) by using a hexagonal wrench.
▶Close all of nut caps (⑤, ⑥) and port caps (⑦, ⑧) of
service valve. Otherwise, refrigerant leakage may occur.
◇ Air purging by vacuum pump (in case length of piping is of 10m of more)
▶Connect piping lines of indoor and outdoor units. (Service valves of gas and liquid are both closed.)
▶Connect low pressure hose (③) of manifold gauge to service port (④) of gas service valve.
▶Open valve of the low pressure hose (①) of manifold gauge, connect vacuum pump as shown in the picture and start purging.
▶Run vacuum pump until gauge pressure reaches [-76cmHg] (for 10 ~ 20 minutes).
▶Close valve of the low pressure hose (①) or manifold
gauge, wait for 3 ~ 4 minutes and check if scale of
pressure gauge has changed. If scale of pressure gauge
has changed, check connection part to prevent refrigerant
leakage in advance.
▶Turn off vacuum pump and disconnect low pressure hose
(③) of manifold gauge from service valve.
▶Completely open gas and liquid service valves by using a
hexagonal wrench.
▶Close all of nut caps (⑤, ⑥) and port caps (⑦, ⑧) of
service valve. Otherwise, refrigerant leakage may occur.
Low High
Vaccumpump
ODU
IDU
Pressuregage
Open Close
Gas
Liquid
ODU
Gas
IDU
Liquid
85
6
10
4
9
3
1
2
7
1
3
54
7
6
8
2
