Emerson Vilter VSS - Coalescing Oil Return Line Setup

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Section 4 • Operation
VSS/VSM/VSH/VSSH • Installation, Operation and Maintenance Manual • Emerson • 35391SD
Coalescing Oil Return Line Setup
Over time, oil will accumulate on the coalescing side
of the oil separator. As a result, an oil return line with a
shut-off valve, sight-glass, check valve and needle valve
are installed between the coalescing side and compres-
sor to return this oil back to the compressor.
To adjust the return ow, proceed with the follow
procedure:
NOTE
Do not fully open the needle valve unless directed by
Vilter
TM
Technical Support. Leaving the needle valve
fully open will reduce efciency of the compressor unit.
1. Open shut-off valve on coalescing side of oil separa-
tor, see Figure 4-13.
2. While the unit is in operation, crack open needle
valve and observe oil ow through sight-glass.
3. Slowly open needle valve more until a small amount
of oil is seen in the sight-glass.
NOTE
The sight-glass should never be full with oil.
4. Periodically check oil in the sight-glass and ensure
that there is ow.
Figure 4-13. Coalescing Oil Return Line
Coalescing Oil Return Line
Needle
Valve
Sight-
Glass
Shut-Off
Valve
Check
Valve