Refrigerant Piping Selection; Installing The Distributor; Twin, Triple And Quad System Installation; Correct Position Of Twin Distributor - Hitachi RPI-10FSNE Installation And Operation Manual

REFRIGERANT PIPING &
REFRIGERANT CHARGE

11.4.2. REFRIGERANT PIPING SELECTION

Select the piping connection sizes according to the following
•
procedures:
Between Outdoor Unit and branch pipe:
-
Select the same pipe connection size as the pipe size of the
Outdoor Unit
Between branch pipe and Indoor Unit:
-
Select the same pipe connection size as the pipe size of the
Indoor Unit
Gas piping Liquid piping
Unit
size size
RASC-5 15.88 (5/8") 9.53 (3/8")
RASC-10 25.4 (1") 12.7 (1/2")
For RASC-10 units, use a reducer pipe in the following
•
installations:
Pipe
Installation
Distributor
Dimensions
type
Type
a
Gas Ø 25.4 Ø 22.2
Single -
Liquid Ø 12.7 Ø 9.53
Twin TE-56N Liquid Ø 9.53 Ø 6.35 indoor 2.0HP
Triple TRE-810N Liquid Ø 12.7 Ø 9.53
Quad QE-810N Liquid Ø 12.7 Ø 9.53

11.4.3. Twin, TRIPLE AND QUAD System Installation

Height Difference Between Indoor Units and Distributor
•
Install all indoor units at the same height. When the
height difference between the indoor units due to building
construction is necessary, this should be less than 0,5
meters. Install the branch pipe at the same height of indoor
units or lower, but never higher.
Sample: Twin system
Height difference between two
indoors. Smaller than 0.5m
Indoor units
Smaller than
0.5mm
Installing Distributor
•
1. Install the Distributor supplied by HITACHI on request
A tee can not be installed instead of a branch pipe.
Sample: Twin System
Distributor
Twin Triple Quad
TE-56N - -
TE-10N TRE-810N QE-810N
Remarks
b
(*)
b
(*)
(*) Single installations with
-
RPI-10HP manufactured
from Feb'07, the reducer is
-
not required.
Branch pipe

2. Installing the Distributor.

Fix the branch pipe horizontally to the pillar, wall or ceiling.
Piping must not be fixed rigidly to the wall as thermal
expansion and contraction can cause pipe fracture.
Sample: Twin System
Horizontal
To indoor
unit
Fixing the branch pipie
To outdoor unit

NOTE:
a
- Fix the piping from outside of insulation or inserting
absorber between the pipe and a fixing metal.

3. Correct position of twin distributor

This is the correct position of twin Branch Pipe:
•
Greater
than 0.5m
This is wrong position.
•
Branch
pipe
4. Correct position of Triple and Quad Distributor.
Install the header horizontally
•
Sample: Triple Branch pipe
Gas piping
Liquid piping
PMGB0126A rev.2 - 11/2006
To indoor
unit
Horizontal
Fixing the branch pipe
to the surface of pillar to ceiling or beam
or wall
Up
Branch
Refrigerant
pipe
direction
Main Pipe
Main Pipe
Refrigerant direction
Down
Up
Main Pipe
Main Pipe
Refrigerant
direction
Branch
Branch
pipe
pipe
Down
Horizontal
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