Refrigerant Piping - Mitsubishi Electric PAC-SF29LB Manuel D'installation

4. Refrigerant Piping

Indoor unit connection example
• Connect one R-Converter unit per indoor unit.
• Connect the R-Converter unit to the liquid pipe.
• The thermistor-L (liquid) is installed close to the connecting point of
the extension piping (liquid) for the indoor unit.
• The thermistor-G (gas) is installed close to the connecting point of
the extension piping (gas) for the indoor unit.
Thermistor-G (gas)
Outdoor unit
MAX. 10 m
R-Converter unit
Piping connection size
Indoor unit capacity
Liquid pipe size (mm)
BTU HP
07 —
09 1
ø6.35 × 0.8
12, 13 1.6
18 2
ø9.52 × 0.8
24, 30 2.5
∗R-Converter unit ø6.35 × 0.8
If using a liquid pipe that is ø9.52 mm, use joint pipe "PAC-493PI" (op-
tional parts)or a locally procured tandem joint (ø6.35 →ø9.52 mm).
Additional refrigerant quantity
• If necessary, add additional refrigerant to the unit by following the
calculation method given in the outdoor unit (PUMY) manual.
• When calculating the refrigerant quantity, be sure to include the R-
Converter unit-to-indoor unit liquid pipe length.
Thermistor-L (liquid)
Indoor unit
Extension piping
connecting point (flare)
Refrigerant piping system
∗ For details, see PUMY series installation manual.
Install sections a, b, c, d and e as shown in the illustration to the R-
Converter unit.
A
A+B+C+D+a+b+c+d+e
L=A+B+C+D+e
r=B+C+D+e
H 30 m (Outdoor lower H
h 12 m
A
B C
B
a
b c
C
C C
A
A+a+b+c+d+e
L=A+e 70 m, r=e
H 30 m (Outdoor lower H
A
h 12 m
B
a b c
C C
C C
• The installation condition for the R-Converter unit - to - indoor unit
are as shown in the illustration below.
• The refrigerant pipe length from the indoor unit to the R-Con-
verter unit must be less than 10 m and its height difference less
than 8 m.
• Install the R-Converter unit within an indoor-unit-to-indoor-unit height
difference of 12 m.
• Match the refrigerant piping size to the indoor unit.
Outdoor unit
R = MAX. 10 m
100 m
70 m
30 m
20 m)
L
R
D
d
e
C
C
A: Outdoor unit
B: First Branch
100 m
C: Indoor unit
30 m
D: Cap
20 m)
L
R
D
e
d
C
Indoor unit
R-Converter unit
R
Indoor unit
5