Daikin Multi+ R32 Split Series - Piping Installation; Preparing Refrigerant Piping; Refrigerant Piping Requirements

7 | Piping installation
Installer reference guide
32
4MWXM-A9
R32 Split series
4P708645-1 – 2022.09
7 Piping installation
In this chapter
7.1 Preparing refrigerant piping................................................................................................................................................... 32
7.1.1 Refrigerant piping requirements ........................................................................................................................... 32
7.1.2 Refrigerant piping insulation.................................................................................................................................. 33
7.1.3 Refrigerant piping length and height difference ................................................................................................... 33
7.2 Connecting the refrigerant piping.......................................................................................................................................... 34
7.2.1 About connecting the refrigerant piping............................................................................................................... 34
7.2.2 Precautions when connecting the refrigerant piping............................................................................................ 34
7.2.3 Guidelines when connecting the refrigerant piping.............................................................................................. 36
7.2.4 Pipe bending guidelines ......................................................................................................................................... 36
7.2.5 To flare the pipe end.............................................................................................................................................. 36
7.2.6 Connections between outdoor and indoor unit using reducers........................................................................... 37
7.2.7 Using the stop valve and service port.................................................................................................................... 38
7.2.8 To connect the refrigerant piping to the outdoor unit ......................................................................................... 40
7.3 Checking the refrigerant piping.............................................................................................................................................. 40
7.3.1 About checking the refrigerant piping................................................................................................................... 40
7.3.2 Precautions when checking the refrigerant piping ............................................................................................... 41
7.3.3 To check for leaks................................................................................................................................................... 41
7.3.4 To perform vacuum drying .................................................................................................................................... 41
7.1 Preparing refrigerant piping
7.1.1 Refrigerant piping requirements
CAUTION
Piping and joints of a split system shall be made with permanent joints when inside
an occupied space except joints directly connecting the piping to the indoor units.
NOTICE
The piping and other pressure-containing parts shall be suitable for refrigerant. Use
phosphoric acid deoxidised seamless copper for refrigerant piping.
INFORMATION
Also read the precautions and requirements in the "2 General safety
precautions"[47].
▪ Foreign materials inside pipes (including oils for fabrication) must be
≤30mg/10m.
Refrigerant piping diameter
Liquid piping Gas piping
4× Ø6.4mm (1/4") 2× Ø9.5mm (3/8")
2× Ø12.7mm (1/2")
INFORMATION
Usage of reducers might be required based on the indoor unit. See
"7.2.6 Connections between outdoor and indoor unit using reducers" [4 37] for
more information.