12
Please  pay  attention  to  avoid  the  components  where  it  is connecting to the connecting pipes.
CAUTION
To  prevent  the  refrigerant  piping  from  oxidizing  inside  when welding, it is necessary to charge nitrogen, or oxide 
will chock the circulation system.
●
Back out pipe:Undersurface outlet pipe: the  knock  out  should  from  inside  to outside, and then piping and wiring 
through this.Pay attention to the piping, the fat connecting pipe should out from the largest hole,  otherwise  the  pipes 
will  be  rubbed.  Please  do the  moth proofing for the knocked out hole, to avoid the pest processing into and destroy 
the components.Please  wipe  off  the  piping  support  rubber  blanket  beside  the inner outlet pipe cover of the machine 
while back side getting out pipes.
A B
Check point of outdoor unit
7.2  Leakage Detection
Use soap water or leakage detector to check every joint whether  leak or not (Refer to Fig.7-2 ).Note: 
A is high pressure side stop valve
B is low pressure side stop valve
C and D is connecting pipes interface of indoor and outdoor units
Check point of indoor unit
D
C
The unit body
Affiliated heat pump belt
Site pipe side
Cut from upward
7.3  Heat Insulation
Do  the  heat  insulation  to  the  pipes  of  gas  side  and  liquid  side separately. The temperature of the pipes of gas side and liquid side when 
cooling,  for  avoiding  condensation  please  do  the  heat  insulation fully.  
1)  The  gas  side  pipe  should  use  closed  cell  foamed  insulation material,  which  the  fire-retardant  is  B1  grade  and  the  heat resistance 
     over 120 
℃.
2)  When  the  external  diameter  of  copper  pipe≤Φ12.7mm,  the thickness of the insulating layer at least more than 15mm; When  the 
     external  diameter  of  copper  pipe≥Φ15.9mm,  the thickness of the insulating layer at least more than 20mm.  
3) Please  use  attached  heat-insulating  materials  do  the  heat insulation without clearance for the connecting parts of the indoor unit pipes. 
Fig.7-2
●
●
Fig.7-3