Hitachi SET FREE MINI RAS-3 Manuel D'installation page 10

2
IMPORTANT NOTICE
2

DANGER:
− Pressure Vessel and Safety Device: This air
conditioner is equipped with a high pressure vessel
under PED (Pressure Equipment Directive). The
pressure vessel has been designed and tested before
shipment according to PED. Also, in order to prevent
the system from an abnormal pressure, a high
pressure switch, which needs no field adjustment, is
utilized in the refrigeration system.
Therefore, this air conditioner is protected from
abnormal pressures. However, if abnormally high
pressure is applied to the refrigeration cycle including
the high pressure vessel(s), it will result in serious
injury or death due to explosion of the pressure
vessel. Do not apply a pressure higher than the
following pressure to the system, by modifying or
changing the high pressure switch.
− Maximum Allowable Pressure and High Pressure Cut-out Value:
No Product Series
1 FSVG Series
2 FSVNE Series
NOTE:
The label for the vessel under PED are attached on
the high pressure vessel. The pressure vessel
capacity and vessel category are indicated on the
vessel.
High Pressure Switch Location
Outdoor Unit Model
RAS-3FSVG to RAS-6FSVG
RAS-3FSVNE to RAS-6FSVNE
No. Description
Accumulator

Compressor

High Pressure Switch

− Start-up and Operation: Check to ensure that all the
stop valves are fully opened and no obstacle exists at
the inlet/outlet sides before start-up and during the
operation.
− Maintenance: Periodically check the high pressure
side pressure. If the pressure is higher than the
maximum allowable pressure, stop the system and
clean the heat exchanger or remove the cause.
Maximun
Refrigerant Allowable
Pressure (MPa)
R407C 3.3
R410A 4.15
NOTE:
The high pressure switch is indicated on the electrical
wiring diagram in the outdoor unit as "PSH"
connected to printed circuit board (PCB1) in the
outdoor unit
High Pressure Switch Structure

DANGER:
− Do not change the high-pressure switch locally or
change the high pressure cut-out set value locally. If
changed, it will cause serious injury or death due to
explosion.
High Pressure
Switch Cut-out
Value (MPa)
3.15 ~ 3.25
4.00 ~ 4.10
No. Description
Connected to

electrical wire
Contact Point

Pressure Detected
