Start-Up; Avoiding Slugging; Connection Of Oil Level Regulator - Danfoss BOCK UL-HGX44e Operating Manual

6 | Commissioning

6.6 Start-up

Check that the safety and protection devices (pressure switch, motor protection, electrical
contact protection measures, etc.) are all functioning properly.
Switch on the compressor and allow to run for a minimum of 10 min.
Check the oil level by: The oil must be visible in the sight glass.

6.7 Avoiding slugging

To prevent slugging:
The complete refrigeration system must be properly designed.
All components must be compatibly rated with each other with regard to output
D
(particularly the evaporator and expansion valves).
US
Suction gas superheat at the compressor input should be min. 7 - 10 K. (check the setting
of the expansion valve).
F
The system must reach a state of equilibrium.
E
Particularly in critical systems (e.g. several evaporator points), measures are recommended such
as replacement of liquid traps, solenoid valve in the liquid line, etc.
There should be no movement of coolant whatsoever while the compressor is at a
standstill.

6.8 Connection of oil level regulator

Oil level regulation systems have proven themselves with parallel circuits of several compressors.
The connection "0" is provided for installing an oil level regulator (see dimensions drawing). All
common oil level regulators from AC&R, ESK and Carly as well as the OM3 TraxOil oil level regulation
system from Alco can be connected directly without adapters (see Fig. 15). A sight glass on the oil
level regulator is not required.
Mechanical oil level regulator
at the "O" connection
26 | AQ450440081306en-US0201
Ensure that both shut-off valves are open before starting the
compressor!
If larger quantities of oil have to be topped up, there is a risk of
oil hammer effects.
If this is the case check the oil return!
Slugging can damage the compressor and cause refrigerant to
leak.
Fig. 15
M6 x 10
3 times each je 3 mal
47,6
3 hole connection diagramm for
3-Loch-Anschlussbild für ESK,
ESK, AC&R and CARLY
AC&R und CARLY
3 hole diagramm for TraxOil 3-Loch-Anschlussbild für TraxOil
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