5.  The  horizontal  pipe  layout  should 
avoid converse flow or bad flow 
Drainage pipe
Water flow
Drainage pipe
Drainage pipe
Drain tee
Drain tee
Water flow
Water flow
Water flow
Water flow
Water flow
Water flow
Water flow
Water flow
Drain tee
 
Branch pipe
Water flow
Water flow
Keep a certain degree
Branch pipe
Gas
Gas
Main pipe
Main pipe
 
  The  correct  installation  will  not  cause 
converse  water  flow  and  the  slope  of  the 
branch pipes can be adjusted freely 
  The  false  installation  will  cause  converse 
water flow and the slope of the branch pipe 
cannot be adjusted. 
6.  Water storage pipe setting 
  If  the  indoor  unit  has  high  extra  static 
pressure  and  without  water  pump  to 
elevate the condensate water, such as high 
extra  static  pressure  duct  unit  ,  the  water 
storage  pipe  should  be  set  to  avoid 
converse flow or blow water phenomena. 
Indoor unit
More than 50mm
More than 25mm
Plug
Water storage pipe
 
7.  Lifting pipe setting of indoor unit with 
water pump 
  The length of lifting pipe should not exceed 
the pump head of indoor unit water pump. 
  The  drainage  pipe  should  be  set  down 
inclined after the lifting pipe immediately to 
avoid wrong operation of water level switch. 
  Refer  the  following  picture  for  installation 
reference.   
Flexible pipe 300mm
Hanger
A
A:Length of horizontal pipe≤150mm
B: Lift height≤the pump head of water pump
Down incline pipe
B
 
8.  Blowhole setting 
  For the concentrated drainage pipe system, 
there  should  design  a  blowhole  at  the 
highest  point  of  main  pipe  to  ensure  the 
condensate water discharge smoothly.   
  The air outlet shall face down to prevent dirt 
entering pipe.   
  Each  indoor  unit  of  the  system  should  be 
installed it. 
  The  installation  should  be  considering  the 
convenience for future cleaning. 
Blowhole
Plug
Indoor unit
Plug
Indoor unit
 
9.  The  end  of  drainage  pipe  shall  not 
contact with ground directly. 
 
14.5.3  Drainage test   
14.5.3.1. Water leakage test 
After finishing the construction of drainage pipe 
system, fill the  pipe with water and keep it for 
24 hours to check whether there is leakage at 
joint section.   
14.5.3.2. Water discharge test 
1.  Natural drainage mode(the indoor unit with   
outdoor drainage pump) 
Infuse above 600ml water through water test 
hole slowly into the water collector, observe 
whether the water can discharge through the 
transparent hard pipe at drainage outlet.