Midea R410A Direct Heating Type HPWH 50Hz Technical Manual                              MCAC-HTSM-201906 
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  Ensure there is enough air flow to supply the heat exchanger, take influence of down draft caused by tall 
building around the unit to air discharge into condenser when installing. 
  If install the unit at a place where ventilation is drastic, such as exposed roofs, short wall or louvers can 
be applied in case of turbulence disturbs air inlet. If short walls are applied, it should be shorter than the 
unit.  Distance  between  short  walls  or  louvers  to  unit  should  either  satisfy  requirements  of  unit 
installation minimum intervals. 
  If  the  unit  runs  in  winter,  and the  location  has  accumulated  snow,  the  unit  should  stand  higher  than 
snow in order to let airflow get through heat exchanger fluently. 
  If the unit is installed in the basement, ensure air around the unit and outdoor air can circulate without 
obstruction. 
2.6 Water pipeline system 
  Water pipe joint specifications of single unit. 
Table 3-2.1:   Water pipe joint specifications for single unit 
  Water  pipeline  system  design  and  construction  must  meet  the  national  water  and  heating  pipeline 
design requirements and relative standards. 
  All the pipes are recommended to use PPR pipe, and the PPR pipe specificatons refers to up table. 
  It must prevent dust and other sundries enter into the pipeline system during the pipeline installation 
and connection. 
  The water flow switch which is used to detect the circulating water flow volume should be prepaired in 
site. The cut-off value of water flow switch is not less than (0.1m3/h×amount of units). 
  Only after unit is fixed, the water pipes can be installed. 
  Use  thermal  insulation  material  to wrap the inlet  water  pipe,  outlet  water pipe  and  circulative  water 
pipes. 
  The pipe diameter of main water pipes: 
 
Table 3-2.2:   Water pipe joint specifications for multi units RSJ-120/ZN1-540V1 
Amount of units connected in parallel