Refrigerant Piping Task; Additional Refrigerant Charge - Mitsubishi MXZ-8B140VA Technical & Service Manual

12

REFRIGERANT PIPING TASK

12-1. ADDITIONAL REFRIGERANT CHARGE

A
H
h1
*1 Although two refrigerant pipes are used between the branch box and the Y-shape
connection pipe when connecting the P100 indoor unit, calculate the piping
lengths using only the length of one pipe.
Total piping length
Farthest piping length (L)
Permissible
length
Piping length between outdoor unit and
(one-way)
branch boxes
Farthest piping length after branch box (I)
Total piping length between branch
boxes and indoor units
In indoor / outdoor section (H) *2
Permissible
height difference
In branch box / indoor unit section (h1)
(one-way)
In each branch unit (h2)
In each indoor unit (h3)
Number of bends
*2 Branch box should be placed with in the level between the outdoor unit and indoor units.
• Additional charging is not necessary for this unit if the total pipe length (b1 + b2 + a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8)
does not exceed 40 m.
• If the total pipe length exceeds 40 m, charge the unit with additional R410A refrigerant according to the permitted pipe
lengths in the chart on the next page.
After charging the unit with refrigerant, note the added refrigerant amount on the service label (attached to the unit).
Refer to the "installation manual" for more information.
OCH480D
b1
B
*1
a1
a2 a3 a4
C
C C C
h3
2
B
c1 c2
b2
B
h2
a5 a6 a7 a8
C C
C
1
1 Indoor unit [P100 type]
2 Y-shape connection pipe
a1 = c1 + c2
C
b1 + b2 + a1+ a2 + a3 + a4 + a5 + a6 + a7 + a8 [ 115m
b2 + a8 [ 70m (b2 [ 55m, a8 [ 15m)
b1 + b2 [ 55m
a8 [ 15m
a1+ a2 + a3 + a4 + a5 + a6 a7 + a8 [ 60m
H [ 30m (In case of that outdoor unit is set higher than indoor unit)
H [ 20m (In case of that outdoor unit is set lower than indoor unit)
h1 + h2 [ 15m
h2 [ 15m
h3 [ 12m
| b1 + a1 |,| b1 + a2 |,| b1 + a3 |,| b1 + a4 |,| b1 + a5 |,| b2 + a6 |,
| b2 + a7 |,| b2 + a8 | [ 15
61
L
I
Outdoor unit
A
Branch box
B
Indoor unit
C
C