Hitachi FSXN1E Series Installation And Operation Manual page 56

Piping work and refrigerant charge
D A N G E R
• Check that the gas and liquid stop valves are fully closed.
• Check that there is no gas inside the pipe before remo-
ving the stop pipe. Otherwise, the pipe may explode
when heated with the blow torch.
Special care should be taken to ensure that the flame from the
blow torch does not fall on the body of the stop valve, on the com-
pressor and cover or on the insulation bushings; insert a metal
plate in front of the oil return pipe: see on chapter
Connect the indoor units to the outdoor units using copper pipes
specifically for use with refrigerant. When laying the pipes make
sure that they do not directly rest on or touch walls or other parts
of the building (when the refrigerant is flowing through the pipes,
this could cause strange noises).
Specific torques for the flared connections: see on chapter
connection mounting.
While welding, apply a flow of nitrogen gas inside the pipe.
Fully insulate the refrigerant pipes.
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Example of installation
For heat pump systems (2 pipes)
• For 3 units combination
Front side piping connection
A Gas pipe (field-supplied)
B Liquid pipe (field-supplied)
C1
Gas connection kit 1
C2 Gas connection kit 2
For heat recovery systems (3 pipes)
• For 3 units combination
Front side piping connection
A Gas pipe, low pressure (field-supplied)
B
Gas pipe, high pressure (field-supplied)
C Liquid pipe (field-supplied)
D1 Gas connection kit, low pressure 1
D2 Gas connection kit, low pressure 2
42
PMML0294A_rev.2_02-2014.indb 42
Gas stop
> 500 mm
D1 Liquid connection kit 1
D2 Liquid connection kit 2
E
Accessory for connection of pipes (L-shaped)
F Outdoor unit 1
E1 Gas connection kit, high pressure 1
E2
Gas connection kit, high pressure 2
F1 Liquid connection kit 1
F2 Liquid connection kit 2
G Accessory for connection of pipes (L-shaped)
PMML0294A rev.2 - 07/2014
C A U T I O N
Fit the pipe protection provided with the outdoor unit on comple-
tion of the installation work. Otherwise, the unit may be damaged
by the entrance of snow, water or rodents
N O T E
For heat pump systems (2 pipes)
valve.
Refer to the Factory-Supplied Accessories
accessory pipes (B) and (C).
Ensure that the closing pipes of the high/low and low pressure
gas stop valves (2 parts) are removed firstly.
For heat recovery systems (3 pipes)
Refer to the Factory-Supplied Accessories
Flared
accessory pipes (A), (B) and (C).
Ensure that the closing pipes of the high/low and low pressure
gas stop valves (1 parts) are removed firstly.
Downward piping connection
G Outdoor unit 2
H Outdoor unit 3
I
Accessory for connection of pipes (Z-shaped)
Downward piping connection
H
I
J
K
N
for the details of the
for the details of the
Outdoor unit 3
Outdoor unit 2
Outdoor unit 1
Accessory for connection of pipes
(Z-shaped)
Accessory for connection of pipes
14/07/2014 12:28:28