Panasonic U-72MF1U9 Technical Data Manual page 18

1. Model Selecting and Capacity Calculator
1-3. Tubing Length
Select the installation location so that the length and size of refrigerant tubing are within the allowable range shown
in the figure below.
L5
H3
C
Balance tubing
(ø3/8")
Explanation of symbols
Distribution joint
1
(purchased separately)
Ball valve (field supply)
T-joint (field supply)
Solidly welded shut
2
(pinch weld)
Note: Do not use commercially available T-joints for the liquid tubing
* Be sure to use special R410A distribution joints (CZ: purchased separately) for outdoor
3
unit connections and tubing branches.
Table 2-1 Ranges that Apply to Refrigerant Tubing Lengths and to Differences in Installation Heights
Item
4
Allowable tubing
length
5
Allowable elevation
6
difference
Allowable length of
joint tubing
L = Length, H = Height
7
NOTE
1: The outdoor connection main tubing (LO portion) is determined by the total capacity of the outdoor units that
are connected to the tube ends.
2: If the longest tubing length (L1) exceeds 295 ft. (equivalent length), increase the sizes of the main tubes (LM)
8 by 1 rank for the discharge tubes, suction tubes, and narrow tubes. (field supplied)
3: If the longest main tube length (LM) exceeds 164 feet, increase the main tube size at the portion before 164 ft.
by 1 rank for the suction tubes and discharge tubes. (field supplied)
(For the portion that exceeds 164 feet, set based on the main tube sizes (LA) listed in the table on the following page.)
1.
2.
3. The outdoor connection main tubing (LO portion) is determined by the total capacity of the
outdoor units that are connected to the tube ends.
4.
LM
B A
LO
LB LC
LA
For
LF extension
Max.1.3 ft
For
extension
Max.1.3 ft
LG
L4
Mark
L1 Max. tubing length
Difference between max. length and min.
L (L2 – L4)
length from the No. 1 distribution joint
LM Max. length of main tubing (at max. diameter)
1 , 2 ... 40 Max. length of each distribution tube
L1+ + 1 2 ... 40 Total max. tubing length including length of
A + B+LF+LG+LH each distribution tube (only liquid tubing)
L5 Distance between outdoor units
When outdoor unit is installed higher than indoor unit
H1
When outdoor unit is installed lower than indoor unit
H2 Max. difference between indoor units
H3 Max. difference between outdoor units
T-joint tubing (field-supply); Max. tubing length between
L3
the first T-joint and solidly welded-shut end point
Main tubing length LM = LA + LB ... < 262 ft
Main distribution tubes LC – LH are selected according to the capacity after the
distribution joint.
Sizes of indoor unit connection tubing 1 – 40 are determined by the connection
tubing sizes on the indoor units.
L1
L2
T-joint tubing
(header joint system)
LD LE L3
4 5 6 7
Solenoid valve kit
LH
3
1 2
and parts.
Contents
Actual length
Equivalent length
2 - 4
Design of 3WAY VRF SYSTEM
_
R410A distribution joint
CZ-P900PH1U (for outdoor unit)
CZ-P224BH1U (for indoor unit)
CZ-P680BH1U (for indoor unit)
CZ-P1350BH1U (for indoor unit)
H1
40
H2
Length (ft.)
<
492
<
574
<
131
<
*2
262
<
98
<
984
<
32
<
164
<
131
<
49
<
13
<
6.6