Engineering Manual

B-129
Installing the refrigerant piping
Permissible
length
(one-way)
Total piping length c1 + b1 + b2 + a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8 ≤ 150 m (492 ft.)
Farthest piping length (L) c1 + b2 + a8 ≤ 80 m (262 ft.)
Piping length between outdoor unit and branch boxes c1 + b1 + b2 ≤ 55 m (180 ft.)
Farthest branch box from the first joint (b2) b2 ≤ 30 m (98 ft.)
Farthest piping length after branch box (l) a8 ≤ 25 m (82 ft.)
Total piping length between branch boxes and indoor units a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8 ≤ 95 m (311 ft.)
Permissible
height difference
(one-way)
In indoor/outdoor section (H) *1 H ≤ 50 m (164 ft.) (In case of outdoor unit is set higher than indoor unit)
H ≤ 40 m (131 ft.) (In case of outdoor unit is set lower than indoor unit)
In branch box/indoor unit section (h1) h1 + h2 ≤ 15 m (49 ft.)
In each branch unit (h2) h2 ≤ 15 m (49 ft.)
In each indoor unit (h3) h3 ≤ 12 m (39 ft.)
Number of bends
| c1 + b1 + a1 |, | c1 + b1 + a2 |, | c1 + b1 + a3 |, | c1 + b1 + a4 |, | c1 + b1 + a5 |, | c1 + b2 + a6 |,
|
c1 + b2 + a7 |, | c1 + b2 + a8 | ≤ 15
*1 Branch box should be placed within the level between the outdoor unit and indoor units.
L
I
h2
b2
b1
c1
5a 6a
2a 3a 4a
h3
h1
H
a1
a7 a8
Fig.
Outdoor unit
Branch box
Indoor unit
The first joint
MXZ-8C48NA MXZ-8C60NA
Operating Range
Indoor intake air temp.
Outoor intake air temp.
M series S, P series
Cooling
Maximum 90 ºFDB, 73 ºFWB 95 ºFDB, 71 ºFWB 115 ºFDB
Minimum 67 ºFDB, 57 ºFWB 67 ºFDB, 57 ºFWB 23 ºFDB
Heating
Maximum 80 ºFDB, 67 ºFWB 80 ºFDB, 67 ºFWB 70 ºFDB, 59 ºFWB
Minimum 70 ºFDB, 60 ºFWB 70 ºFDB, 60 ºFWB -4 ºFWB
MXZ-4C36NAHZ MXZ-5C42NAHZ MXZ-8C48NAHZ
Operating Range
Indoor intake air temp.
Outoor intake air temp.
M series S, P series
Cooling
Maximum 90 ºFDB, 73 ºFWB 95 ºFDB, 71 ºFWB 115 ºFDB
Minimum 67 ºFDB, 57 ºFWB 67 ºFDB, 57 ºFWB 23 ºFDB
Heating
Maximum 80 ºFDB, 67 ºFWB 80 ºFDB, 67 ºFWB 70 ºFDB, 59 ºFWB
Minimum 70 ºFDB, 60 ºFWB 70 ºFDB, 60 ºFWB -13 ºFWB
Pipe length and height difference
Flared connections
• This unit has flared connections on each indoor unit and branch box and outdoor unit sides.
• Remove the valve cover of the outdoor unit, then connect the pipe.
• Refrigerant pipes are used to connect the branch box and outdoor unit.