Refrigerant Piping Requirements; Refrigerant Piping Material; To Select The Piping Size - Daikin LRMEQ4BY1 Installer And User Manual

5 Preparation
Item
Piping diameter Must comply with requirements. See
"5.3.2 Refrigerant piping requirements" on
Piping material
page 12.
Piping length and
height difference
Piping insulation If deteriorated, must be replaced.
Must comply with requirements. See
"6.6 To insulate the refrigerant piping" on
page 21.
Welded connections Must be checked for gas leaks.
Cleaning piping If the old condensing unit did NOT use the
same refrigerant (R410A) and the same oil
(FVC68D) as the new one, you must clean
the piping to remove any residue.
5.3.2

Refrigerant piping requirements

INFORMATION
Also read the precautions and requirements in the
"General safety precautions" chapter.
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.
5.3.3

Refrigerant piping material

▪ Piping material: Phosphoric acid deoxidised seamless copper.
▪ Piping temper grade and thickness:
Outer diameter Temper grade
(Ø)
6.4 mm (1/4") Annealed (O)
9.5 mm (3/8")
12.7 mm (1/2")
15.9 mm (5/8") Annealed (O)
19.1 mm (3/4") Half hard (1/2H)
(a) Depending on the applicable legislation and the unit's
maximum working pressure (see "PS High" on the unit
name plate), larger piping thickness might be required.
5.3.4

To select the piping size

Determine the proper size using the following tables and reference
figure (only for indication).
Installer and user reference guide
12
Description
(a)
Thickness (t)
Ø
≥0.80 mm
t
≥0.99 mm
≥0.80 mm
1
A B C D2
D1
F E
H
2 2 3
e
f d1
a b c d2
1 Outdoor unit
2 Indoor unit (Showcase)
3 Indoor unit (Blower coil)
A~F Liquid piping
a~f Gas piping
H Height difference outdoor-indoor
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 22.
A/a: Piping between outdoor unit and piping
branching
Liquid piping
Gas piping
(a) Same diameter as the connection on the outdoor unit.
(b) Use the accessory piping to adapt the diameter of the
outdoor unit stop valve (Ø15.9 mm) to that of the field
piping (Ø19.1 mm).
B+C/b+c: Piping between piping branching
Use diameters depending on the total capacity of the indoor units
connected downstream.
LRMEQ3+4 Capacity
Liquid piping <4.0 kW
4.0≤x<8.4 kW
Gas piping <1.0 kW
1.0≤x<6.0 kW
6.0≤x<8.4 kW
(a) For showcases, capacity is calculated at evaporating
temperature –10°C. For blower coils, capacity is calculated
at temperature difference (= evaporating temperature –
room temperature) of 10°C.
LRLEQ3+4 Capacity
Liquid piping
Gas piping <2.3 kW
2.3≤x<3.62 kW
(a) For showcases, capacity is calculated at evaporating
temperature –35°C. For blower coils, capacity is calculated
at temperature difference (= evaporating temperature –
room temperature) of 10°C.
3
(a)
Ø9.5 mm
(b)
Ø19.1 mm
(a)
Piping outer
diameter
Ø6.4 mm
Ø9.5 mm
Ø9.5 mm
Ø12.7 mm
Ø15.9 mm
(a)
Piping outer
diameter
— Ø6.4 mm
Ø12.7 mm
Ø15.9 mm
LRMEQ+LRLEQ3+4BY1
Air-cooled refrigeration condensing unit
4P500362-1A – 2018.09