Hisense kf-2302gwe User Guide

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Many of conventional split system air conditioners 
employ  the  flaring  method  to  connect  refrigerant 
tubes  which  run  between  indoor  and  outdoor  units. 
In  this  method,  the  copper  tubes  are  flared  at 
each end and connected with flare nuts.
5-2.Flaring Procedure with a Flare Tool
(1)Cut the copper tube to the required length with 
a tube cutter. It is recommended to cut approx. 
30-50cm  longer  than  the  tubing  length  you 
estimate.
(2)Remove burrs at the end of the copper tube with 
a  tube  reamer  or  file.  This  process  is 
important  and  should  be  done  carefully  to  make 
a good flare. (Fig.30)
When  reaming,  hold  the  tube  end  downward  and  be 
sure  that  no  copper  scraps  fall  into  the  tube. 
(Fig.31)
(3)Remove the flare nut from the unit and be sure 
to mount it on the copper tube.
(4)Make  a  flare  at  the  end  of  copper  tube  with  a 
flare tool.*(Fig.32)
     (*Use“RIGID”or equivalent.)
good 
flare 
should 
have 
the 
following 
characteristics:
·inside surface is glossy and smooth.
·edge is smooth.
·tapered sides are of uniform length.
5-3.Caution before Connecting Tubes Tightly
a)  Be  sure  to  apply  a  sealing  cap  or  water-proof 
tape to prevent dust or water from getting into 
the tubes before they are used.
b)  Be  sure  to  apply  refrigerant  lubricant  to  the 
matching surfaces of the flare and union before 
connecting them together. This is effective for 
reducing gas leaks.(Fig.33a)
c) For proper connection, align the union tube and 
flare tube straight with each other, then screw 
in  the  flare  nut  lightly  at  first  to  obtain  a 
smooth match. (Fig.33b)
5-4.Connecting  Tubing  between  Indoor  and  Outdoor 
Units
a)Tightly  connect  the  indoor  side  refrigerant 
tubing 
extended  from 
the  outdoor 
side 
tubing.(Fig.34)
B)  To  fasten  the  flare  nuts,  apply  specified 
torque as:
NOTE
NOTE
Tube Dia.
6.35mm
12.7mm
9.52mm
Tightening Torque
Approx.15-20N.m
Approx.50-55N.m
Approx.35-40N.m
5.5 Insulation of  Refrigerant Tubing
IMPORTANT
To prevent heat loss and wet floors due to dripping of
Cabinet
Access
panel
“C”
Fig.29
Before
After
Deburring
Fig.30
Copper
tubing
Reamer
Fig.31
Flare nut
Copper
tubing
Flare tool
Fig.32
Apply refrigerant
lubricant here and there
Union 
Flare nut
Fig.33a
Fig.33b