Refrigerant Piping Work - York MKL/MKM 25 Technical Manual

REFRIGERANT PIPING WORK

Refrigerant piping is import 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 unit will drop. As the number of bends increase, resistance
to flow of refrigerant system increase, thus lowering cooling capacity and as a result the compressor may become
defective. Always choose the shortest path and follow the recommendation as tabulated below.
MODEL
Max. length (m)
Max. elevation (m)
Max. no. of bends
Liquid pipe size
Gas pipe size
Piping Connection
• Do not use contaminated or damaged copper tubing. If any piping, evaporator or condenser had been exposed or
had been opened for 15 seconds or more, than vacuum and purge with field supplied refrigerant. Generally, do not
remove plastic, rubber plugs and brass nuts from the valves, fitting, tubing and coils units it is ready to connect
suction or liquid line into valves or fittings.
• If any brazing work is required, ensure that nitrogen gas is passed through coil and joints while the brazing work is
being done. This will eliminate soot formation on the inside wall of copper tubing.
• Cut the pipe stages by stages, advancing the blade of pipe cutter slowly. Extra force and a deep cut will cause more
distortion of pipe and therefore 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 until which is pre-charge with refrigerant R407C, 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.
02_MKL-MKM.p65
INDOOR MKL-MKM 25
OUTDOOR MOL-MOM 25
15 m
8 m
10
3/8"
5/8"
9
MKL-MKM 35 MKL-MKM 45
MOL-MOM 35 MOL-MOM 45
20 m 20 m
10 m 10 m
10 10
3/8" 3/8"
5/8" 3/4"
13/6/02, 11:08 am
YORK CASSETTE (EN) 035T76015-000
MKL-MKM 55
MOL-MOM 55
20 m
10 m
10
3/8"
3/4"
9
CASSETTE