Refrigerant Piping System - Mitsubishi Electric City Multi PQHY-P-YLM-A series Installationshandbuch

Copper pipe size and radial thickness for R410A CITY MULTI.
Radial thickness
Size (mm) Size (in)
(mm)
ø6.35 ø1/4 0.8
ø9.52 ø3/8 0.8
ø12.7 ø1/2 0.8
ø15.88 ø5/8 1.0
*ø19.05 ø3/4 1.2
*ø19.05 ø3/4 1.0
ø22.2 ø7/8 1.0
ø25.4 ø1 1.0
ø28.58 ø1-1/8 1.0
ø31.75 ø1-1/4 1.1
ø34.93 ø1-3/8 1.2
ø41.28 ø1-5/8 1.4
* Both pipe types can be used for pipe size ø19.05 mm (3/4 in) for R410A air
conditioner.
6 Use a fitting if a specified refrigerant pipe has a different diameter from that
of a branching pipe.
7 Follow the restrictions on the refrigerant piping (such as rated length, height
difference, and piping diameter) to prevent equipment failure or a decline in
heating/cooling performance.
Indoor twinning pipe set model PQHY-P·Y(S)LM-A ONLY
Line branch
Down-stream unit Down-stream unit
model model
Less than 200 in More than 201 and
total less than 400 in total
CMY-Y102SS-G2 CMY-Y102LS-G2
Indoor twinning pipe set model PQHY-P·Y(S)LM-A ONLY
Header branch
4 branching 8 branching
CMY-Y104-G CMY-Y108-G
Heat source twinning kit model PQHY-P·Y(S)LM-A ONLY
Total heat source model Total heat source model
P400 ~ P600
CMY-Y100VBK3
8 Indoor units cannot be further branched down stream after the branch
header. (See diagram below.) *PQHY-P·Y(S)LM-A ONLY.
To the heat source unit
To the heat source
unit
9 A lack or an excess of refrigerant can cause the unit to stop. Charge the
system with the appropriate amount of refrigerant. When servicing, always
check the information concerning pipe length and amount of additional
refrigerant at the refrigerant volume calculation table on the back of the
service panel and the additional refrigerant section on the labels for the
combined number of indoor units (Refer to item 9.2. for detailed information
on refrigerant piping system).
0 Charge the system using liquid refrigerant.
a Never use refrigerant to air purge. Always evacuate using a vacuum
pump.
b Always insulate the piping properly. Insufficient insulation will result in
a decline in heating/cooling performance, condensation and other such
problems (Refer to item 10.4 for insulation of the refrigerant piping).
c When connecting the refrigerant piping, make sure the valve of the heat
source unit is completely closed (the factory setting) and do not operate
it until the refrigerant piping for the heat source unit, indoor units and
BC controller has been connected, a refrigerant leakage test has been
performed, and the evacuation process has been completed.
d Braze only with non-oxided material. Failure to do so may damage the
compressor. Braze using nitrogen purge.
Do not use any commercially available anti-oxidizing agent, because it
may cause pipe corrosion and degrade the refrigerant oil.
Contact Mitsubishi Electric for more details.
(Refer to item 10.2. for details of the piping connection and valve operation)
e Never perform piping connections when raining.
Radial thickness
Pipe type
(mil)
32 Type-O
32 Type-O
32 Type-O
40 Type-O
48 Type-O
40 Type-1/2H or H
40 Type-1/2H or H
40 Type-1/2H or H
40 Type-1/2H or H
44 Type-1/2H or H
48 Type-1/2H or H
56 Type-1/2H or H
Down-stream unit Down-stream unit
model model
More than 401 and More than 651 in
less than 650 in total total
CMY-Y202S-G2 CMY-Y302S-G2
10 branching
CMY-Y1010-G
P700 ~ P900
CMY-Y200VBK2
CAP
Warning:
When installing and relocating the unit, do not charge the system with any
other refrigerant other than what is specified.
- Mixing different refrigerant, air, etc. may cause the refrigerant cycle to
malfunction and result in severe damage.
Caution:
• Use a vacuum pump with a reverse flow check valve.
- If the vacuum pump does not have a reverse flow check valve, the vacuum
pump oil may flow back into the refrigerant cycle and cause deterioration of
the refrigerant oil.
• Do not use the tools shown below used with conventional refrigerant.
(Gauge manifold, charge hose, gas leak detector, check valve,
refrigerant charge base, vacuum gauge, refrigerant recovery
equipment)
- Mixing of conventional refrigerant and refrigerant oil may cause the
refrigerant oil to deteriorate.
- Mixing of water will cause the refrigerant oil to deteriorate.
- R410A refrigerant does not contain any chlorine. Therefore, gas leak
detectors for conventional refrigerants will not react to it.
• Manage tools used for R410A carefully.
- If dust, dirt, or water gets in the refrigerant cycle, the refrigerant oil will
deteriorate.
• Never use existing refrigerant piping.
- The large amount of chlorine in conventional refrigerant and refrigerant oil
in existing piping will cause the new refrigerant to deteriorate.
• Store the piping to be used during installation indoors and keep both
ends of the piping sealed until just before brazing.
- If dust, dirt, or water get into the refrigerant cycle, the oil will deteriorate
and the compressor may fail.
• Do not use a charging cylinder.
- Using a charging cylinder may cause the refrigerant to deteriorate.
• Do not use special detergents to wash the piping.

9.2. Refrigerant piping system

Example of refrigerant piping system
[Fig. 9.2.1] (P.4, P.6 - 7)
Heat source model
Gas side
Liquid pipe
Model number
The 1st branch of P450 ~ P650
Joint
4-Branch header (Downstream unit model total ≤ 200)
8-Branch header (Downstream unit model total ≤ 400)
10-Branch header (Downstream unit model total ≤ 650)
Heat source twinning kit
A Heat source unit
C Indoor unit
E Heat source twinning kit
*1 ø12.7 for over 90 m [295-1/4 in]
*2 ø12.7 for over 40 m [131-3/16 in]
*4 The pipe sizes listed in columns A1 to A2 in this table correspond to the sizes
for the models listed in the unit 1 and 2 columns. When the order of the models
for unit 1 and 2 change, make sure to use the appropriate pipe size.
*5 B If the piping length after the first joint exceeds 40 m (≤ 90 m), use the one
size larger liquid pipe for the indoor unit. (for PQHY-P·Y(S)LM-A)
*6 C When the height difference between the indoor units is 15 m or greater
(≤ 30 m), use the one size larger liquid pipe for the indoor unit (lower side). (for
PQHY-P·Y(S)LM-A)
[Fig. 9.2.2] (P.5 - 7)
Heat source model
Low-pressure side
Liquid pipe
Model number
Heat source twinning kit
Low-pressure gas pipe
A Heat source unit
C BC controller (main)
E Indoor unit (15 ~ 80)
G Heat source twinning kit
*3 When the piping length is 65 m or longer, use the ø28.58 [1-1/8] pipe for the
part that exceeds 65 m.
*4 The pipe sizes listed in columns A1 to A2 in this table correspond to the sizes
for the models listed in the unit 1 and 2 columns. When the order of unit 1 and
2 is changed, make sure to use the appropriate pipe size for the model.
Liquid side
Total capacity of indoor units
Gas pipe
Downstream unit model total
The first branch of P700 ~ P900
B 1st branch
D Cap
F Header
High-pressure side
Total capacity of indoor units
Gas pipe
Downstream unit model total
High-pressure gas pipe
B BC controller (standard)
D BC controller (sub)
F Indoor unit (100 ~ 250)
25