Flooded type water cooled screw chiller (PCB Control)
89
When the unit is in stable operation, the oil level in the high oil immersion lens should be at least above
the 1/2 position. And there shall be no deterioration (blackness) of the lubricating oil, or else, qualified
lubricating oil shall be changed before operating the unit.
6) Inspect whether the pressure sensor stop valve, dry filter front/rear angle valve and liquid/air sampling
stop valve etc. are all opened.
When the unit stops, the high and low voltages shall be almost the same. After the start-up, the low
voltage decreases, and the high voltage increases. If there is no voltage change certain time after the
start-up, inspect whether the liquid/air sampling stop valve is open.
7) After the unit is installed and before connected, it is principle required to tighten the connections in the
electrical cabinet of the unit one by one.
8) Inspect the bolts of the unit for looseness.
After the unit is transported and installed, it is required to inspect whether the fixing bolts of the unit (e.g.
fixing bolts at compressor base angle, at post and beam of the unit, and at pipe clamp, etc.) and of the
electrical elements (e.g. fixing bolts of PCB and of insulating transformer, and connection bolts of
upper/lower terminals of AC contactor, etc.) are firmly fixed.
9) Inspect the connections in the electrical cabinet for looseness, especially the electric part in the
cabinet. The parts connected by bolts might be loose due to transportation. If there is any looseness,
tighten it to avoid burnout of circuit or element caused by poor contact.
Inspect the terminals for looseness and poor contact caused by vibration and collision during
transportation and installation (especially the electric part; ensure the connection points of all terminals
are firm and reliable before electrification).
Inspect whether there is poor contact and short circuit caused by dust, moisture, etc. in the electrical
cabinet, and whether the values of all temperature sensors are normal. During the shutdown of the
machine, the indicated temperatures of discharge, fin, and the environment shall be almost the same,
The oil must be full in stop
status of the unit, and above
the 1/2 position in stable
operation.
All connection points
of terminals must be
firm and reliable.
Inspect all terminals
for
firmness
and
reliability
before
electrification.
