Midea MGA-D10/N1 Manual page 51

Installation
3.3.2 Refrigerant Piping
Note:
1. Refrigerant piping connection is on the right side of outdoor unit.
2. The piping connects to refrigerant piping connection.
3. Install the refrigerant piping towards left, right or back.
4. Refer to system identifiers in valve installation board for corresponding connections of indoor units.
a. Choose the sizes of refrigerant piping: φ9.5+φ19
b. Connection: refer to connection of refrigerant piping
c. Length and height drop permitted of refrigerant piping
Maximum length of piping (L)
Maximum height drop
(Height drop between water pump box and outdoor unit H)
d. Remove dirt or water in the piping
● Make sure there is no any dirt or water in the piping before connecting it to the outdoor unit.
● Please clean the piping with high-pressure nitrogen rather than refrigerant of outdoor unit.
e. Vacuuming with vacuum pump
● Please vacuum with vacuum pump.
● Vacuuming should be done from the gas side.
f. O pen all valves
g. R efrigerant volume to be added
Calculate the volume according to the diameter and the length of the liquid side piping between
outdoor unit and water pump box. The refrigerant volume to be added is based on the following table:
Piping on liquid side
<5m
≥5m
Expel the air
1. Flaring
Cut a pipe with a pipe cutter.
Insert a flare nut into a pipe and flare the pipe.
2. Fasten the nuts
Put the connecting tubing at the proper position, wrench the nuts with hands then fasten it with a wrench.
50
Method
Use refrigerant in outdoor unit
Use vacuum pump or refrigerant box
MCAC-UTSM-2008-11
Outdoor unit (up)
Outdoor unit (down)
Refrigerant volume to be added
60g/m× (length of piping -5m)
10m
5m
5m
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Installation