3 Piping work and refrigerant charge
Refrigerant and drain hose installation
SMGB0099 rev.0 - 12/2016
122
X
Y(*)
INCORRECT
CORRECT
Incorrect: 
Upward 
Slope
Incorrect: 
Rising 
Part
Common Drain Piping
Drain 
trap
Drain Piping 
connection
1/25~1/100 
Down Slope
! CAUTION
•  It is very important the syphon installation in order to guarantee the proper condensate draining.
•  Do not create an upper-slope or rise for the drain piping, since drain water will ow back to the unit and leakage to the room will occur 
when the unit operation is stopped.
•  Do not connect the drain pipe with sanitary or sewage piping or any other drainage piping.
•  When the common drain piping is connected with other indoor units, the connected position of each indoor unit must be higher than 
the common piping. The pipe size of the common drain pipe must be large enough according to the unit size and number of unit.
•  Drain piping will require insulating if the drain is installed in a location where condensation forming on the outside of drain pipe may 
drop and cause damage. The insulation for the drain pipe must be selected to insure vapour sealing and prevent condensation 
forming.
•  Drain trap should be installed next to indoor unit. This trap must be designed to good practice and be checked with water (charged) 
and tested for correct ow. Do not tie or clamp the drain pipe and refrigerant pipe together.
? NOTE
•  (*)Y distance must be higher than X.
•  Install drainage in accordance with national and local codes.
After performing drain piping work and electrical wiring, check to ensure that water ows smoothly as in the following 
procedure:
Checking Unit without drain-up mechanism
 - Pour approximately 1.8 litres of water into the drain pan (in each unit).
 - Check to ensure that the water ows smoothly or whether no water leakage occurs.  When water cannot be found 
at the end of the drain piping, pour another approximately 1.8 litres of water into the drain pan of each unit.
? NOTE
•  Pay attention to the thickness of the insulation when the left side piping is performed. If it is too thick, piping can not be installed in 
the unit.
•  If there is excessive clearance between the drain pipe connection and the drain hose, add a sealing material between both parts in 
order to t and not deform the drain hose.