Acson international A4LC 20B, Manual

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48
Refrigerant piping is important in particular. Refrigeration cycle of the split air conditioner is realized
by the perfect piping work.
PIPING LENGTH AND ELEVATION
If the piping is too long, both the capacity and reliability of the unit will drop. As the number of bends increases,
resistance to flow of refrigerant increases, thus lowering the cooling capacity and as a result overloading the compressor
which may cause the compressor to become defective. Always choose the shortest path and follow the recommendation
as tabulated below.
Indoor ACK15B/BR
ACK20A/AR
ACK20B/BR ACK25A/AR
ACK25B/BR ACK30A/AR
ACK30B/BR
ACK40A/AR ACK50A/AR
MODEL
Outdoor ALC15B/BR ALC20B/BR ALC25B/BR ALC30B ALC30C/CR ALC40C/CR ALC50C/CR
Max. length (m) 10 15 15 15 35 35 35
Max. elevation (m) 5 8 8 8 15 15 15
Max. no. of bends 10 10 10 10 10 10 10
Liquid pipe size 1/4" 1/4" 3/8’’ 3/8’’ 3/8’’ 3/8" 3/8’’
Gas pipe size 1/2” 5/8” 5/8’’ 5/8’’ 5/8’’ 3/4'’ 3/4'’
PIPING CONNECTION
Do not use contaminated or damaged copper tubing. If piping for evaporator or condenser are exposed or had been
opened for 15 seconds or more, vacuum and purge with field supplied refrigerant. Generally, do not remove plastic,
rubber plugs and brass nuts from valves, fittings, tubing and coils until it is ready to do the connection for suction and
liquid line.
If any brazing work is required, ensure that nitrogen gas is passed through coil and joints while brazing work is being
carried out. This will eliminate soot formation on the inside wall of copper tubing.
Cut the pipe stage by stage, advance the blade of pipe cutter slowly. Extra force and deep cut will cause more distortion
of pipe and therefore produce extra burr.
Remove burrs from cut edges of pipes with a remover. This will avoid unevenness on the flare face which will cause gas
leak.
Align the center of the piping and sufficiently tighten the flare nut with fingers. Finally, tighten the flare nut with torque
wrench until the wrench clicks.
Be sure to execute heat insulation (polyurethane form with thickness more than 15 mm).
Except the outdoor unit which is pre-charged with refrigerant, the indoor unit and the refrigerant connection pipes must
be purged because the air that contain moisture remaining in the refrigerant cycle may cause malfunction to the
compressor.
ADDITIONAL CHARGE
The refrigerant is pre-charged in the outdoor unit, but additional charge of refrigerant after vacuuming is necessary.
Follow the recommendation as tabulated below.
Coo
ling Only
INDOOR ACK20A ACK25A ACK30A ACK40A ACK50A
MODEL
OUTDOOR ALC20B ALC25B ALC30C ALC40C ALC50C
L <= 5 m 0.250 0.100 0.400 - -
L = 7 m 0.280 0.176 0.600 0.100 0.100
L = 10 m 0.325 0.290 0.650 0.250 0.250
L = 15 m 0.400 0.480 0.900 0.500 0.500
L = 20 m - - 1.150 0.750 0.750
L = 35 m - - 1.500 1.500 1.500
11. REFRIGERANT PIPING WORK