6 Piping installation
Installation manual
9
CTXF20~35C5V1B
Daikin room air conditioners
3P519299-13V – 2020.08
a
b
a
b
a
Insulation fixing screw
b
Drain hose
4
Attach the drain hose to the refrigerant piping bottom side using
adhesive vinyl tape.
A
B
C
b
a
A
Left-side piping
B
Left-back piping
C
Left-bottom piping
a
Remove the pipe port cover here for left-side piping
b
Remove the pipe port cover here for left-bottom piping
To check for water leaks
1
Remove the air filters.
2
Gradually pour approximately 1 l of water in the drain pan, and
check for water leaks.
6
Piping installation
6.1
Preparing refrigerant piping
6.1.1
Refrigerant piping requirements
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.
Refrigerant piping diameter
Use the same diameters as the connections on the outdoor units:
Class
L1 liquid piping
L1 gas piping
20~35
Ø6.4
Ø9.5
Refrigerant piping material
▪
Piping material:
Phosphoric acid deoxidised seamless copper.
▪
Piping temper grade and thickness:
Outer diameter
(Ø)
Temper grade
Thickness (t)
(a)
6.4 mm (1/4")
Annealed (O)
≥0.8 mm
t
Ø
(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.
6.1.2
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
(Ø
p
)
Insulation inner
diameter (Ø
i
)
Insulation thickness
(t)
6.4 mm (1/4")
8~10 mm
≥10 mm
Ø
i
Ø
i
t
Ø
p
Ø
p
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.
6.2
Connecting the refrigerant piping
DANGER: RISK OF BURNING/SCALDING
WARNING
▪ Only use R32 as refrigerant. Other substances may
cause explosions and accidents.
▪ R32 contains fluorinated greenhouse gases. Its global
warming potential (GWP) value is 675. Do NOT vent
these gases into the atmosphere.
▪ When charging refrigerant, ALWAYS use protective
gloves and safety glasses.
6.2.1
Guidelines when connecting the
refrigerant piping
Take the following guidelines into account when connecting pipes:
▪ Coat the flare inner surface with ether oil or ester oil when
connecting a flare nut. Tighten 3 or 4 turns by hand, before
tightening firmly.
▪ ALWAYS use 2 wrenches together when loosening a flare nut.
▪ ALWAYS use a spanner and torque wrench together to tighten the
flare nut when connecting the piping. This to prevent nut cracking
and leaks.
