2.  Pump drainage mode 
  2.1  Disconnect  the  plug  of  water  level  switch, 
remove the cover of water test hole and slowly 
infuse  about  2000ml  water  through  the  water 
test hole, be sure that the water will  not touch 
the motor of drainage pump. 
 
 
2.2  Power  on  and  let  the  air  conditioner 
operate for cooling. Check operation status 
of  drainage  pump,  and  then  connect  the 
plug  of  water  level  switch,  check  the 
operation  sound  of  water  pump  and 
observe  whether  the  water  can  discharge 
through  the  transparent  hard  pipe  at 
drainage  outlet.  (In  light  of  the  length  of 
drainage  pipe,  water  shall  be  discharged 
about 1 minute delayed)   
2.3  Stop the operation of air conditioner, power 
off the  power supply and  put  the  cover of 
water test hole back to the original place. 
a.  After stopped the air conditioner 3 minutes, 
check whether there is anything abnormal. 
If drainage pipes have not been distributed 
properly, over back-flow water shall cause 
the  flashing  of  alarm  indicator  at 
remote-controlled  receiving  board  and 
even  water  shall  run  over  the  water 
collector. 
b.  Continuously  infusing  water  until  water 
level alarmed, check whether the drainage 
pump  could  discharge  water  at  once.  If 
water level does not decline under warning 
water  level  3  minutes  later,  it  shall  cause 
shutdown  of  unit.  When  this  situation 
happens,  the  normal  startup  only  can  be 
recovered  by  turning  down  power  supply 
and eliminating accumulated water. 
Note:  Drain  plug  at the  main  water-containing 
plate is used for eliminating accumulated water 
in  water-containing  plate  when  maintaining  air 
conditioner fault.  During normal  operation,  the 
plug shall be filled in to prevent leakage. 
 
14.5.4  Insulation work of drainage pipe 
Refer  the  introduction  to  the  insulation 
engineering parts. 
 
14.6 Vacuum Drying and Leakage 
Checking 
14.6.1  Purpose of vacuum drying 
  Eliminating  moisture  in  system  to  prevent 
the phenomena of ice-blockage and copper 
oxidation.