Panasonic U-72MF1U9 Technical Data Manual page 22

1. Model Selecting and Capacity Calculator
1-5. Installation Standards
Relationship between A/C units and refrigerant tubing
Outdoor unit
Install the solenoid valve kit 98 ft. or less from the indoor unit.
In quiet locations such as hospitals, libraries, and hotel rooms, the refrigerant noise may be somewhat noticeable. It is recom-
mended that the solenoid valve kit be installed inside the corridor ceiling, at a location outside the room.
Room
Indoor unit
Hallway
1
Common solenoid valve kit
Multiple indoor units under group control can utilize a solenoid valve kit in common.
2
Categories of connected indoor unit capacities are determined by the solenoid valve kit.
Type of solenoid valve kit
160
56
If the capacity range is exceeded, use 2 solenoid valves connected in parallel.
3
(2) When adding ball valve for outdoor unit
1. Location: Install the ball valve at the main tube of the distribution joint.
4
5
6
2. Installation requirements
• Be sure to install the ball valve up-grade to prevent the inadvertent flow of oil.
• Install the ball valve at the shortest distance (within 1.3 ft.) from the main tube. If the diameter of the ball valve
7
is smaller than that of the main tube, use a reducer or the like to reduce the size of the tubing at that location.
NOTE
• If the ball valve is installed at the outdoor unit (including extension for outdoor unit), face the service port of
8
the valve toward the outdoor unit side (see above illustration; dotted line) and allow a distance of over 1.6 ft
from the outdoor unit. If the ball valve is installed between the indoor unit (including extension for indoor unit)
and the main tube, face the ball valve toward the indoor unit side (see above illustration; dotted line).
• Use a field supply ball valve.
4-tube layout
Outdoor unit
Suction tube
Discharge tube
Liquid tube
Balance tube
Desirable
Room
Indoor unit
Total capacity of indoor units (BTU/h)
19.000 < Total capacity
7.500 Total capacity
Outdoor unit
for extension
Ball valve (for extension)
(Planned expansion)
Main tube of distribution joint
3-tube layout Solenoid
valve kit
Suction tube
Discharge tube
Liquid tube
Room
Indoor unit
Hallway
Solenoid
valve kit
54.600
19.000
Balance tube
Discharge tube
Less than 1.3 ft
2 - 8
Design of 3WAY VRF SYSTEM
2-tube layout
Indoor unit
Gas tube
Liquid tube
Undesirable
Room
Indoor unit
Distribution joint
(Suction tube)
Main tube
Liquid tube
To indoor unit
Solenoid
valve kit