Refrigerant Piping Size - Hitachi RAS-3.0HNSKQ Original Instruction

(2) Precaution for branch pipe connection
Use the branch pipe to connect the outdoor/indoor units. Mounted the branch pipes to a pillar, a wall, or a
ceiling.
Keep the inlet pipe of the branch pipe straight, and the length of the straight pipe is no less than 0.5 meter.

4.3 Refrigerant Piping Size

Example of connection: connection of 4 indoor units.
Model
RAS-3.0~7.0HNSKQ
Table 4.1 Piping Size of Main Pipe
Stop Valve(mm)
Gas Liquid
Φ15.88 Φ9.53
Pipe between the outdoor unit and the 1st branch pipe;
The pipes between the branch pipes.
Gas
Φ15.88
23
Liquid Marks
Φ9.53▲ a; b; c