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VSS/VSR/VSM/VSH/VSSH Compressor • Installation, Operation and Service Manual • Emerson • 35391S
Section 1 • General Information
Bare Shaft Refrigeration and Heat Pump Compressor Model Designations
The compressor bare shaft model designation can be found on the nameplate.
VSS – 1851 – CIH – STR – SD – A – VIB
Compressor Type
CIH- Standard Cast Iron Material
w/Discharge Connection
Horizontal
CID- Standard Cast Iron Material
w/Discharge Connection Down
STH- Steel Compressor Material w/
Discharge Connection Horizontal
DIH- Ductile Iron (750 MAWP) w/
Discharge Connection Horizontal
DIHST- Ductile Iron (750MAWP)
w/Steel Housing, Discharge
Connection Horizontal
DID- Ductile Iron Material w/
Discharge Connection Down
Special Designations
MV- Manual Volume Slide
MCV- Manual Capacity and
Volume Slide
CC- Cool Compression
EX- Expander
O- Large Economizer Port
AF- AFLAS O-rings
PC - Slide Piston C ast Iron
EO - External Oil Feed
VIB- Main Housing with
Vibration Mounting
LT- 205mm LITE Compressor
B- Balanced Main Rotor
PPS- Slide with Ryton Clamps
N- 900# Flange
PPC- Carbon Slide Clamp
Drive Shaft Type
STD- Standard Drive shaft
(tapered or straight)
STR- Straight Shaft for
Heavy Duty
SDS- Severe Duty Straight
Shaft
Slide Design Type
SD- Standard Slide Assembly
LR- Low Ratio Slide
HR- Standard Slide (Balance
Grooves for >325 PSID)
FR- Fixed Ratio Single Slide
RS- Reinforced Shaft Rack
FV- Fixed Volume
Alphabet*- 205mm LITE
compressor
Size
CFM- Nominal CFM
displacement of the
compressor at 3600
rpm
Seal Type
A- Ammonia Service
H-Halocarbon Service
TA- Tandem Seal for
Ammonia Service
TH- Tandem Seal for
Halocarbon Service
AH- Ammonia Service High
Pressure
AHF- Ammonia Service
High Pressure Aas O-ring
HV- High Pressure Design
w/ Viton o-rings
Compressor Model
VSS- Vilter Single Screw
Compressor
VSM-Vilter Single Mini Screw
Compressor
VRS- Vilter Twin Screw
Compressor
VSR- Vilter Single Gaterotor
Compressor
VSH- Vilter Single Screw Heat
Pump
VSSH- Vilter Single Screw
Heat Pump (High Pressure)
Note- *: 205mm LITE compressor-
Use alphabet of slide number used
in compressor BOM.
Example: 26376A then slide
designation: A.