DC Inverter U-match Series Floor Ceiling Type Unit 
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(3).  When pipes are repeatedly bent or stretched, the material will harden, making 
it difficult to bend or stretch them any more. Do not bend or stretch the pipes 
more than three times. 
(4).  When bending the pipe, do  not bend it as is. 
The pipe will be collapsed. In this case, cut the 
heat  insulating  pipe  with  a  sharp  cutter  as 
shown in Fig. 4.10, and bend it after exposing 
the pipe. After bending the pipe as you want, 
be sure to put the heat insulating pipe back on 
the pipe, and secure it with tape. 
 
①.  To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of curvature of 150 
mm or over. 
②.  If the pipe is bent repeatedly at the same place, it will break. 
 
5.3.3 Connecting the Pipe at the Indoor Unit Side 
Detach the caps and plugs from the pipes. 
①.  Be sure to apply the pipe against the port on the indoor unit correctly. If the centering is improper, 
the  flare  nut  cannot  be  tightened smoothly.  If  the  flare nut  is  forced to  turn,  the  threads  will  be 
damaged. 
②.  Do not remove the flare nut until the connection pipe is to be connected so as to prevent dust and 
impurities from coming into the pipe system. 
When connecting the pipe to the unit or removing it from the unit, please do use 
both the spanner and the torque wrench.(Fig. 4.11) 
When connecting, smear both inside and outside of the flare nut with refrigeration 
oil, screw it hand tight and then tighten it with the spanner. 
Refer to Table 4.3    to check if the wrench has been tightened properly (too tight 
would mangle the nut and lead to leakage). 
Examine  the  connection  pipe  to  see  if  it  leaks,  then  take  the  treatment  of  heat 
insulation, as shown in the Fig. 4.12. 
Use the medium-sized sponge to insulate the coupler of the gas pipe.