Preparing Refrigerant Piping; Refrigerant Piping Requirements; To Select The Piping Size - Daikin RWEYQ8T9Y1B Installer And User Manual

D When there are no smaller room divisions:
E When there is a room division that has an opening
sufficiently large to permit free air flow.
a
a Opening between the rooms. In case there is a door
the openings above and below the door each must be
equivalent in size to 0.15% or more of the floor area.
b Room division
3 Calculate the refrigerant density using the results of the
calculations in steps 1 and 2 above. If the result of the above
calculation exceeds the maximum concentration level, a
ventilation opening to the adjacent room shall be made.
Formula: F/G≤H
F Total volume of refrigerant in the refrigerant system.
G Size (m³) of smallest room in which there is an indoor unit
installed.
H Maximum concentration level (kg/m³).
4 Calculate the refrigerant density using the total volume of the
room where the indoor unit is installed and the adjacent room.
Install ventilation openings in other doors of adjacent rooms
until the resulting refrigerant density is smaller than the
maximum concentration level.
5.3

Preparing refrigerant piping

5.3.1

Refrigerant piping requirements

NOTICE
The refrigerant R410A requires strict cautions for keeping
the system clean, dry and tight.
▪ Clean and dry: foreign materials (including mineral oils
or moisture) should be prevented from getting mixed
into the system.
▪ Tight: R410A does not contain any chlorine, does not
destroy the ozone layer, and does not reduce earth's
protection against harmful ultraviolet radiation. R410A
can contribute slightly to the greenhouse effect if it is
released. Therefore pay special attention to check the
tightness of the installation.
NOTICE
The piping and other pressure-containing parts shall be
suitable for refrigerant. Use phosphoric acid deoxidised
seamless copper for refrigerant.
▪ Foreign materials inside pipes (including oils for fabrication) must
be ≤30 mg/10 m.
RWEYQ8~14T9V1B + RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1 – 2017.04
b
▪ Temper grade: use piping with temper grade in function of the
pipe diameter as listed in table below.
Pipe Ø Temper grade of piping material
≤15.9 mm
≥19.1 mm
▪ All piping lengths and distances have been taken into
consideration (see "5.3.4 About the piping length" on
▪ The pipe thickness of the refrigerant piping shall comply with the
applicable legislation. The minimal pipe thickness for R410A
piping must be in accordance with the table below.
Pipe Ø
6.4 mm/9.5 mm/12.7 mm
15.9 mm
19.1 mm/22.2 mm
28.6 mm
34.9 mm
41.3 mm
▪ In case the required pipe sizes (inch sizes) are not available, it is
also allowed to use other diameters (mm sizes), taken the
following into account:
▪ Select the pipe size nearest to the required size.
▪ Use the suitable adapters for the change-over from inch to mm
pipes (field supply).
▪ The additional refrigerant calculation has to be adjusted as
mentioned in "6.7.3 To determine the additional refrigerant
amount" on page 28.
5.3.2

To select the piping size

INFORMATION
Please select the proper pipe sizes depending on the
mode of your system. There are 2 possible modes:
▪ heat pump,
▪ heat recovery.
Determine the proper size using the following tables and reference
figure (only for indication).
In case of heat pump mode
A
a x
D F
b 3
G
E
1 2 4 5
1,2 VRV DX indoor unit
3 BP box
4,5 RA DX indoor unit
a,b Indoor branch kit
x,y Outdoor multi connection kit
5 Preparation
O (annealed)
1/2H (half hard)
page 15).
Minimal thickness t
0.80 mm
0.99 mm
0.80 mm
0.99 mm
1.21 mm
1.43 mm
B B B
C
y
Installer and user reference guide
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