Hitachi UTOPIA IVX PREMIUM Série Manuel D'utilisation page 19

REFRIGERANT PIPING & REFRIGERANT CHARGE
Spindle Type
 Spindle valve
 Flare nut
 Cap
  C heck joint for service port
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)
Hexagonal wrench size used for spindle valve:
2HP, 2.5HP
(*) Size
Gas valve
Liquid valve
Do not apply two
spanners at this
position. If applied,
leakage will occur
Do not work with two
spanners here.
Refrigerant leakage
shall occur
Use two spanners here
for pipe connection
8.3 BRAZING WORK
!
C A U T I O N
• Use nitrogen gas for blowing during pipe brazing. If oxygen, acetylene or fluorocarbon gas is used, it will cause an explosion or poisonous gas.
• A lot of oxidation film will occur inside of tubes if no nitrogen gas blowing is performed during brazing work. This film will be flecked off after
operation and will circulate in the cycle, resulting in clogged expansion valves, etc. This will cause bad influence to the compressor.
• Use a reducer valve when nitrogen gas blowing is performed during brazing. The gas pressure should be maintained within 0.03 to 0.05MPa. If a
excessively high pressure is applied to a pipe, it will cause an explosion.
9 PMML0398B rev.0 - 11/2015 - P5416651
Stop valve (liquid)
Stop
valve
(gas)
Closed upon factory shipping
Refrigerant pressure
Refrigerant piping
Hexagonal wrench
(field supplied) (*)
3HP
4 mm 5 mm
4 mm 4 mm
Stop valve
(Spindle type)
Flare nut

Outdoor unit
Gas Liquid
valve valve
RAS-(2-2.5)HVNP1 7-9 7-9
RAS-3HVNC1 9-11 7-9
RAS-3HVRNS3 9-11 7-9
!
C A U T I O N
• At the test run, fully open the spindle and ball stop valve.
• If not fully opened, the devices will be damaged.
• Do not attempt to turn service valve rod beyond its stop.
• Do not loosen the stop ring. If the stop ring is loosened, it is dangerous
since the spindle will hop out.
• An excess or a shortage of refrigerant is the main cause of trouble
to the units. Charge the correct refrigerant quantity according to the
description of label at the inside of service cover.
• Check for refrigerant leakage in detail. If a large refrigerant leakage
occurs, it will cause difficulty with breathing or harmful gases would
occur if a fire was being used in the room.
8.2.2 Connecting flare adapter
Flare nut (accessories)
Liquid line
Pipe
(field
supplield)
Gas line
The piping sizes for indoor unit and outdoor unit are different.
Attach the flare adapter (accessories) at the indoor piping union
part.
Use the adequate flare adapter as follows:
Indoor unit
2.0 HP
2.5 HP
Tightening Torque (Nm)
 
Gas Liquid Gas Liquid Gas
valve valve valve valve valve
34-42 34-42 33-42 33-42 14-18
68-82 34-42 33-42 33-42 14-18
68-82 34-42 33-42 33-42 14-18
Pipe (accessories)
Flare adapter (accessories)
Flare adapter
Gas pipe Liquid pipe
Big size
( 15.88→ 12.70)
∅ ∅
Big size Small size
( 15.88→ 12.70) ( 9.52→
∅ ∅ ∅

Liquid
valve
14-18
14-18
14-18
Indoor unit
-
6.35)
∅