Piping Installation; Preparing Refrigerant Piping; Refrigerant Piping Requirements; Refrigerant Piping Insulation - Daikin FXFN71A2VEB Installation And Operation Manual

13 Piping installation

a Plastic watering can
b Service drain outlet (with rubber plug). Use this outlet to
drain water from the drain pan
c Drain pump location
d Drain pipe connection
e Drain pipe
5 Turn OFF the power.
6 Disconnect the electrical wiring.
▪ Remove the service cover.
▪ Disconnect the power supply.
▪ Disconnect the user interface.
▪ Reattach the service cover.
When installation of the system is already completed
1 Start cooling operation (see the reference guide or the service
manual of the user interface).
2 Gradually pour approximately 1 l of water through the water
inlet, and check for leaks (see
completed" [ 4 17]).
is not yet
13 Piping installation
13.1

Preparing refrigerant piping

13.1.1

Refrigerant piping requirements

NOTICE
Refrigerant R744 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 and oil. Use K65 copper-iron alloy
tube system for high-pressure applications with a working
pressure of 120 bar at the air conditioner side and 90 bar
at the refrigeration side.
▪ Foreign materials inside pipes (including oils for fabrication) must
be ≤30 mg/10 m.
NOTICE
If the ability to close the stop valves for field piping is
wanted, the installer MUST install a pressure relief valve
on the following piping:
▪ Outdoor unit to refrigeration indoor units: on liquid
piping
▪ Outdoor unit to air conditioning indoor units: on liquid
piping AND gas piping
Installation and operation manual
18
e
d
c
b
a
"When installation of the system
Refrigerant piping diameter
Liquid piping
Ø9.5 mm
Refrigerant piping material
▪ Piping material: K65 copper-iron alloy (CuFe2P), maximum
operating pressure = 120 bar
▪ Piping temper grade and thickness:
Outer diameter Temper grade
(Ø)
9.5 mm (3/8") R420
12.7 mm (1/2")
(drawn)
(a)
Depending on the applicable legislation and the maximum
working pressure of the unit (see "PS High" on the unit name
plate), larger piping thickness might be required.
13.1.2

Refrigerant piping insulation

▪ Use polyethylene foam as insulation material:
▪ with a heat transfer rate between 0.041 and 0.052 W/mK (0.035
and 0.045 kcal/mh°C)
▪ with a heat resistance of at least 120°C
▪ Insulation thickness
Pipe outer diameter Insulation inner
(Ø ) diameter (Ø
p
9.5 mm (3/8") 10~14 mm
12.7 mm (1/2") 14~16 mm
Ø Ø
i i
Ø Ø
p p
t
If the temperature is higher than 30°C and the humidity is higher
than RH 80%, the thickness of the insulation materials should be at
least 20 mm to prevent condensation on the surface of the
insulation.
13.2

Connecting the refrigerant piping

DANGER: RISK OF BURNING/SCALDING
13.2.1 To connect the refrigerant piping to the
indoor unit
CAUTION
Install the refrigerant piping or components in a position
where they are unlikely to be exposed to any substance
which may corrode components containing refrigerant,
unless the components are constructed of materials that
are inherently resistant to corrosion or are suitably
protected against corrosion.
▪ Pipe length. Keep refrigerant piping as short as possible.
Gas piping
Ø12.7 mm
(a)
Thickness (t)
Ø
≥0.65 mm
t
≥0.85 mm
Insulation thickness
) (t)
i
≥10 mm
≥10 mm
FXFN50~112A2VEB
CO₂ Conveni-Pack: indoor unit
3P672850-1B – 2022.01