Lubrication/Oil Level Monitoring; Set High-Pressure And Low-Pressure Limiters (Hp + Lp); Set The Condenser Pressure; Vibrations And Frequencies - Bitzer CSH6553-35Y Instructions De Service

6.6.2

Lubrication/oil level monitoring

• Check the lubrication of the compressor directly after
the compressor start.
The oil level must be visible in the zone of both sight
glasses.
• Check the oil level repeatedly within the first hours of
operation!
During the start phase, oil foam may arise but its level
should decrease at stable operating conditions. Other-
wise high proportions of liquid in the suction gas are
suspected.
NOTICE
!
!
Risk of wet operation!
Maintain the discharge gas temperature well
above the condensing temperature: at least
20 K.
at least 30 K for R407A, R407F and R22.
NOTICE
!
!
Risk of liquid slugging!
Before adding larger quantities of oil: check the
oil return!
6.6.3 Set high-pressure and low-pressure limiters (HP
+ LP)
Check exactly the cut-in and cut-out pressure values
according to the operating limits by testing them.
6.6.4

Set the condenser pressure

• Set the condenser pressure so that the minimum
pressure difference is reached within 20 s after the
compressor start.
• Avoid quick pressure reduction with finely stepped
pressure control.
Application limits, see BITZER Software, manual
SH-170 and brochure SP-171 (CSH) / SP-172 (CSW).
6.6.5

Vibrations and frequencies

Check the system carefully to detect any abnormal vi-
bration, check particularly pipelines and capillary tubes.
In case of strong vibrations, take mechanical meas-
ures: e.g. use pipe clamps or install vibration dampers.
NOTICE
!
!
Risk of burst pipes and leakages on the com-
pressor and system components!
Avoid strong vibrations!
48
6.6.6

Checking the operating data

• Evaporation temperature
• Suction gas temperature
• Condensing temperature
• Discharge gas temperature
– min. 20 K above condensing temperature
– min. 30 K above condensing temperature for
R407C, R407F and R22
– max. 120°C on the outside of the discharge gas
line
• Oil temperature directly under the oil sight glass
• Cycling rate
• Current values
• Voltage
• Prepare data protocol.
Application limits, see BITZER Software, manual
SH-170 and brochure SP-171 (CSH) / SP-172 (CSW).
6.6.7

Control logic requirements

NOTICE
!
!
Risk of motor failure!
The specified requirements must be ensured by
the control logic!
• Desirable minimum running time: 5 minutes!
• Minimum standstill time:
– 5 minutes
This is the time the control slider needs to reach
the optimal start position.
– 1 minute
Only if the compressor has been shut off from the
25%-CR step!
– Also observe minimum standstill times during
maintenance work!
• Maximum cycling rate:
– CS.65 and CS.75: max. 6 starts per hour
– CS.85 and CS.95: max. 4 starts per hour
• Switching time of the motor contactors:
– Part winding: 0.5 s
– Star-delta: 1 to 2 s for CS.65, CS.75 and CS.85
– Star-delta: 1.5 to 2 s for CS.95
SB-170-7