Gree FG20/BNa-M, Service Manual

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47
Duct Type Split Air Conditioner
Service Manual
3 REFRIGERATION PIPING WORK
3.1 Refrigeration Piping Work Procedures
1).
Align the flared end of the copper pipe with the center of the thread joint. Manually tighten the flared
end nut.
2).
Use torque spanner to tighten the flared end nut until the spanner clatters.
Fitting Pipe for
Indoor unit
Flaring Nuts Fitting Pipe
Spanner
Torque Spanner
3.2 Caution in Connecting Pipes
Note: Do not loosen the cap of the pipes when connecting the pipes between the indoor unit
and the outdoor unit. Connecting the pipes as soon as possible after loosening the cap of the pipes
to avoid the entering of water and dust. A metal pipe should be utilized if a pipe should be installed
through a wall.
1).
The connection of the pipes should confirm to the following principles:
2). Make sure to lessen the length of connecting pipe, the height difference between the
indoor and outdoor unit, and the number of bends, and enlarge the diameter of bends.
The permitted maximum value of each case
Height difference between the indoor and outdoor unit
＜
30m
90
0
Number of bends
＜
12
Length of connecting pipes
＜
50m
The pipe meld type could be employed for the connection of the pipes between the indoor and outdoor
units.
The pipe joint should be tightly connected when a pipe joint is employed between two pipes. It is better to
use only one connecting pipe if the distance is not far.
The pipes should not be shriveled when the pipes are connecting. The bend diameter should be longer
than 200 millimeter. The connecting pipes should not be extended or curved frequently and the curving process
should not be larger than 3 times in the same bending position.
3.3 Specification of Connection Pipe
Model
External Diameter
Maximum Length
of Connection Pipe
(m)
Maximum Difference in
Height between Outdoor
and Indoor Unit (m)
Max.No. of
elbows. (90
o
)
Additional
Charge of
Refrigerant (g/m)
Gas Pipe
(Inch)
Liquid Pipe
(Inch)
FG20/BNa-M
3/4″ 3/8″
50 30 12 60
FGR20/BNa-M
FG25/CNa-M
1″ 3/8″
50 30 12 60
FGR25/CNa-M
FG30/BNa-M
9/8″ 1/2″
50 30 12 120
FGR30/BNa-M
FG40/BNa-M
9/8″ 5/8″
50 30 12 170
FGR40/BNa-M