Bitzer HS.8551 Mode D'emploi page 22

– Automatic sequence change for systems with sev-
eral refrigerating circuits (approximately every 2
hours).
– Mount an additional check valve in the discharge
gas line if no temperature and pressure compens-
ation is reached even after long standstill times.
– If needed, mount a time and pressure-dependent
controlled pump down system or suction side suc-
tion accumulators – particularly for high refrigerant
charges and/or when the evaporator may become
hotter than the suction gas line or the compressor.
• For further information about pipe layout, see
manual SH-110.
I I n n f f o o r r m m a a t t i i o o n n
In the case of refrigerants with low isentropic ex-
ponent (e.g. R134a), a heat exchanger between
the suction gas line and the liquid line may have
a positive effect on the system's operating mode
and coefficient of performance.
Arrange the temperature sensor of the expan-
sion valve as described above.
7 7 O O p p e e r r a a t t i i o o n n
7 7 . . 1 1 R R e e g g u u l l a a r r t t e e s s t t s s
Check the system at regular intervals according to na-
tional regulations. Check the following points:
• Operating data, see chapter Operation, page 22.
• Oil supply, see chapter Operation, page 22.
• Safety and protection devices and all components
for compressor monitoring (check valves, discharge
gas temperature limiters, differential oil pressure
switches, pressure limiters, etc.).
• Tight seat of electrical cable connections and
screwed joints.
• Screw tightening torques.
• Check refrigerant charge.
• Tightness test.
• Update data protocol.
22 22
8 8 M M a a i i n n t t e e n n a a n n c c e e
8 8 . . 1 1 A A r r r r a a n n g g i i n n g g f f o o r r r r e e m m o o v v a a l l c c l l e e a a r r a a n n c c e e s s
When installing the compressor in the system, arrange
for sufficiently large clearances for removal and main-
tenance:
• HS.95: for dismantling the slider maintenance ac-
cess cover to replace the entire slider unit, provide a
minimum clearance of 70 mm for unscrewing the
screws forward!
• HS.85: in front of the oil filter chamber, for replace-
ment of the internal oil filter (see figure 13, page
23).
8 8 . . 2 2 I I n n t t e e g g r r a a t t e e d d p p r r e e s s s s u u r r e e r r e e l l i i e e f f v v a a l l v v e e
The valve is maintenance-free.
However, after repeated venting, it may leak constantly
due to abnormal operating conditions. The con-
sequences are reduced performance and a higher dis-
charge gas temperature. Check the valve and replace it
if necessary.
8 8 . . 3 3 I I n n t t e e g g r r a a t t e e d d c c h h e e c c k k v v a a l l v v e e
If the check valve is defective or contaminated, the
compressor runs for some time in reverse direction
after it has been switched off. The valve must then be
changed.
Recommended replacing interval: 20,000 .. 40,000 h.
W W A A R R N N I I N N G G
The compressor is under pressure!
Serious injuries are possible.
Depressurize the compressor!
Wear safety goggles!
8 8 . . 4 4 O O i i l l s s t t o o p p v v a a l l v v e e
In case of damage or contamination, the compressor
can be charged with oil during a prolonged shut-off
period.
HS.85: Valve installed on the compressor as part of the
oil management system.
HS.95: External solenoid valve.
SB-110-3 RUS SB-110-3