Hitachi RAS-2HVNP Installations- Und Betriebshandbuch Seite 24

14
1 Refrigerant piping & refrigerant charge
14.2 PIPING CONNECTION FOR OUTDOOR UNIT
1 Take the piping cover away from the unit. Then fetch the pipes
through the rear side and route piping according to the ins-
tallation place as shown in the figure. Make holes by cutting
along the guideline at the rear of the cover or punching with
a driver. Remove the burr with a cutter, and place a insulation
(field supplied) to protect cables and pipes.
Rear side
piping
Direction to remove pipe cover
2 Attach the pipe cover in order to prevent rainwater from ente-
ring inside the cabinet.
3 Use a pipe bender for pipe bending work when connecting
pipes.
4 Check to ensure that the stop valves are completely closed
before connecting pipes.
5 Connect the field supplied refrigerant pipes to the indoor unit
and outdoor unit. Apply the oil thinly at the seat flare nut and
pipe before tightening.
The required tightening torque is as follows:
Pipe Size
Ø 6.35 mm (1/4)
Ø 9.52 mm (3/8)
Ø 12.70 mm (1/2)
Ø 15.88 mm (5/8)
Ø 19.05 mm (3/4)
Do not work with
two spanners
here.
Refrigerant
leakage shall
occur
24
Pipe cover
Stop valve
Tightening Torque (Nm)
20
40
60
80
100
Use two spanners
here for pipe con-
nection
PMML0248A
6 After connecting the refrigerant piping, seal the open space
between knockout hole and refrigerant pipes by using insula-
tion material.
Unit
Side
Connec-
ting piping
7 Operation of stop valve should be performed according to the
figure below.
8 Close before shipment
14.2.1 Outdoor unit stop valve
Operation of stop valve should be performed according to the
figures and tables below:
Spindle Type

Spindle valve

Flare nut

Cap

Check joint for service port
Outdoor unit
RAS-(2-2.5)HVNP
RAS-3HVNC
RAS-3HVRNS3
Spindle valve
Tighten the spindle with a torque above:
Counterclockwise.... Open
Clockwise .... Close
Closed before shipment
Check joint
(Only charging hose can
be connected)
Tighten the cap with 16 N.m torque.
Cap
Tighten the cap with 37 N.m torque
(Attach this after work)
Nº
Insulation Material

Insulation Material

Field Supplied

Insulation Material

Tightening Torque (Nm)
 
Gas Liquid Gas Liquid
valve valve valve valve valve
7-9 7-9 33-42 33-42 33-42
9-11 7-9 68-82 33-42 33-42
9-11 7-9 68-82 33-42 33-42
Refrigerant
pressure
Description
Stop valve (liquid)
Stop valve (gas)
 
Gas Liquid Gas Liquid
valve valve valve
33-42 14-18 14-18
33-42 14-18 14-18
33-42 14-18 14-18
Refrigerant piping
Hexagonal wrench
(field supplied) (*)