Horizontal Installation; Vertical Installation; Pipe Selection - Mitsubishi Electric CITY MULTI PUHY-P72TNU-A-B Manuel D'installation

・Restriction on installing the indoor unit twinning kit CMY-Y202S-G2 or CMY-Y302S-G2 on the gas piping
To outdoor unit or heat source unit
- - The indoor unit twinning kit on the gas piping must be installed horizontally (as shown in the figure at left below)
or with the branched pipes facing up (as shown in the figure at right below).
- - If the size of the refrigerant pipe that is selected by following the instructions under section 9-4 does not match
the size of the indoor unit twinning kit, use a reducer to connect them. A reducer is included in the indoor unit
twinning kit.

Horizontal installation

±15° or less
・If the length of the pipe between the branching point and the outdoor unit exceeds 2 m (6 ft), provide a trap within 2
m (6 ft) from the branching point.
The trap must be at least 200 mm (7-7/8 in) in height. (gas pipe only) If there is no trap, oil can accumulate inside
the pipe, causing a shortage of oil and may damage the compressor.
* Small dots in the figures indicate branching points.
2 m (6 ft)
To indoor units
Ⓐ
Ⓑ Trap (gas pipe only)
Ⓒ Gas pipe

9-2. Pipe selection

Use refrigerant piping made of phosphorus deoxidized copper (copper and copper alloy
seamless pipes) that meets local requirements. Pipe joints should also meet local
requirements. Keep the inner and outer surfaces of the pipes clean and free of sulphur,
oxides, dust/dirt, shaving particles, oils, moisture, or any other contaminants.
- Contaminants on the inside of the refrigerant piping will cause the refrigerant oil to deteriorate
and cause the compressor to malfunction.
Use refrigerant pipes for use with R410A refrigerant system. Piping for systems for use with other types of refrigerants
may not be able to be used.
Use refrigerant pipes with the thicknesses specified in the table below.
Size [mm (in)] Minimum wall thickness [mm (in)]
ø6.35 (ø1/4)
ø9.52 (ø3/8)
ø12.7 (ø1/2)
ø15.88 (ø5/8)
ø19.05 (ø3/4)
ø22.2 (ø7/8)
ø25.4 (ø1)
ø28.58 (ø1-1/8)
ø31.75 (ø1-1/4)
ø34.93 (ø1-3/8)
ø41.28 (ø1-5/8)
WT09452X01
To indoor unit (branched pipe)

Vertical installation

Indoor-unit side (branched pipe)
Outdoor-unit or heat-source-unit side (main pipe)
Ⓐ
0.67 (0.0265)
0.72 (0.0285)
0.72 (0.0285)
0.8 (0.0315)
0.98 (0.0385)
1.04 (0.0410)
1.17 (0.0460)
1.17 (0.0460)
1.28 (0.0505)
1.28 (0.0505)
1.41 (0.0555)
* The branched pipes must face up.
±15° or less
Ⓑ
Ⓐ
Ⓒ
≤ 2 m (6 ft)
GB-25