Recommendations When Servicing (Compressors Without Slide Valves); Preparation Of Unit For Servicing - Emerson Vilter VSS Installation, Operation & Maintenance Manual

Section 5 • Maintenance/Service
Recommendations when Servicing
(Compressors Without Slide Valves)
When working on the compressor, care must be taken to
ensure that contaminants (i.e. water from melting ice, dirt
and dust) do not enter the compressor while it is being
serviced. It is essential that all dust, oil or ice that has ac-
cumulated on the outside of the compressor be removed
before servicing the compressor.
After servicing the compressor, all gaskets, O-rings, roll
pins and lock washers must be replaced when reassem-
bling the compressor.

Preparation of Unit For Servicing

WARNING
Follow local lock-out/tag-out procedure. Compressors
must be depressurized before attempting to do any
work on them. Failure to comply may result in serious
injury, death and/or damage to equipment.
A) Shut down the unit, open the electrical disconnect
switch and pull the fuses for the compressor motor
to prevent the unit from starting. Put a lock on the
disconnect switch and tag the switch to indicate that
maintenance is being performed.
WARNING
Be cautious when isolating sections of CO
CO has a very steep pressure curve, and as sections
2
containing CO warm up, pressures can rise
2
dramatically & well beyond system design.
WARNING
When working with LFG, NG or other dangerous
or fl ammable gases, ensure there are adequate
ventilation and vapor detectors. Refer to national fi re
and building codes. Failure to comply may result in
serious injury or death.
WARNING
Avoid skin contact with any condensate or oil. Wear
rubber gloves and a face shield when working with
condensate or oil. Failure to comply may result in
serious injury or death.
5 – 6
piping.
2
VSS/VSM/VSH/VSSH • Installation, Operation and Maintenance Manual • Emerson • 35391SD
B) Isolate the unit by manually closing the discharge Stop
valve. Allow the unit to equalize to suction pressure
before closing the Suction Bypass. After the unit
has equalized to suction pressure and suction valve
closed, use an acceptable means to depressurize the
unit that complies with all Local, State and Federal
Ordinances.
WARNING
At shutdown, open any other valves that may trap
liquids to prevent serious injury and/or damage to
equipment.
NOTICE
Recover or transfer all gas vapor in accordance with
local ordinances before opening the compressor unit
to the atmosphere.
C) Remove drain plugs from the bottom of compressor
housing and the discharge manifold. Drain the oil
into appropriate containers.