Compressor Unit Isolation For Maintenance/Service (Compressors With Slide Valves) - Emerson VILTER VSS Installation, Operation And Service Manual

Section 5 • Maintenance/Service
Compressor Unit Isolation For
Maintenance/Service (Compressors
with Slide Valves)
WARNING
Avoid skin contact with any liquid refrigerant or oil.
Wear rubber gloves and a face shield when working
with liquid refrigerant or oil. Failure to comply may
result in serious injury or death.
WARNING
When working with refrigerants, ensure there is
adequate ventilation and refrigerant vapor detectors
as per ASHRAE standards. Failure to comply may
result in serious injury or death.
WARNING
At shutdown, open any other valves that may trap
liquids to prevent serious injury and/or damage to
equipment.
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.
NOTICE
Recover or transfer all refrigerant vapor in accordance
with local ordinances before opening any part of the
package unit to atmosphere.
The compressor unit must be isolated and depressurized
to atmosphere prior to servicing.
Figure 5-1. Discharge Bleed Valve, Suction Equalizing Line and Valve
VSS/VSR/VSM/VSH/VSSH Compressor • Installation, Operation and Service Manual • Emerson • 35391S
1. Shut down the compressor unit, refer to Stopping/
Restarting procedure in Section 4.
2. Turn motor and oil pump starter disconnect switch-
es into the OFF position. Lock-out/tag-out discon-
nect switches.
3. If suction equalizing valve is not open, open it to
allow oil separator pressure to vent to low-side
system pressure, see Figure 5-1. Close valve when
complete.
4. Isolate the compressor unit by closing all valves to
the house system. Lock-out/tag-out valves.
If drain valves are installed on suction and discharge
headers, open these valves too to remove build up
of liquid during shut-down periods.
5. Open any other valves that may trap gas or liquid.
Lock-out/tag-out valves.
6. Recover and/or transfer all vapors per local/state
codes and policies.
7. Servicing the compressor unit can proceed at this
point. After servicing, ensure to perform a leak
check, see Compressor Unit Leak Check procedure.
Suction
Equalizing Line
NOTE
Suction
Equalizing Valve
Discharge
Bleed Valve
5 – 5