Refrigerant Piping Requirements; Refrigerant Piping Material; To Select The Piping Size; To Select Refrigerant Branch Kits - Daikin LRLEQ3BY1 Installation And Operation Manual

4 Preparation
Item
Piping insulation If deteriorated, must be replaced.
Must comply with requirements. See
"5.5 To insulate the refrigerant piping" on
page 17.
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.
4.2.2

Refrigerant piping requirements

NOTICE
Refrigerant R410A requires strict cautions for keeping the
system clean and dry. Foreign materials (including mineral
oils or moisture) should be prevented from getting mixed
into the system.
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.
4.2.3

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.
4.2.4

To select the piping size

Determine the proper size using the following tables and reference
figure (only for indication).
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
Installation and operation manual
10
Description
(a)
Thickness (t)
Ø
≥0.80 mm
≥0.99 mm
≥0.80 mm
3
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 "5.6.2 To determine the additional refrigerant
amount" on page 17.
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
Liquid piping
Gas piping
(a) For showcases, capacity is calculated at evaporating
temperature –10°C. For blower coils, capacity is calculated
at temperature difference (= evaporating temperature –
t
room temperature) of 10°C.
LRLEQ3+4
Liquid piping
Gas piping
(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.
D~F/d~f: Piping between piping branching and
indoor unit
Use the same diameters as the connections (liquid, gas) on the
indoor units.
NOTICE
If only 1 indoor unit is connected to the outdoor unit, and
the connections on the outdoor unit are different from
those on the indoor unit, then use the same piping
diameter as the connections on the outdoor unit, and install
suitable adapters as near to the indoor unit as possible.
4.2.5

To select refrigerant branch kits

For refrigerant piping branching, it is allowed to use T-joints, Y-joints,
refnet joints, and refnet headers. It is possible to use a refrigerant
branching option kit from the table below.
Description
(a)
Refnet header
(a)
Ø9.5 mm
(b)
Ø19.1 mm
(a)
Capacity Piping outer
diameter
<4.0 kW Ø6.4 mm
4.0≤x<8.4 kW Ø9.5 mm
<1.0 kW Ø9.5 mm
1.0≤x<6.0 kW Ø12.7 mm
6.0≤x<8.4 kW Ø15.9 mm
(a)
Capacity Piping outer
diameter
— Ø6.4 mm
<2.3 kW Ø12.7 mm
2.3≤x<3.62 kW Ø15.9 mm
Model name
KHRQ22M29H
LRMEQ+LRLEQ3+4BY1
Air-cooled refrigeration condensing unit
4P545024-1 – 2018.09