070.250-IOM (APR 11)
Page 5
408 MM ROTARY SCREW COMPRESSOR
INSTALLATION - OPERATION - MAINTENANCE
Break vacuum with dry nitrogen and bring pressure to zero
psig.
Pump oil into the same ports mentioned in step 1. Johnson
Controls-Frick recommends break-in oil P/N 111Q0831809
for storage purposes. The amount of oil needed is:
408 XL 120 gallons
408 L 115 gallons
408 S 100 gallons
After the compressor is oil charged, pressurize compressor
to 15 psig with nitrogen.
MAINTAINING COMPRESSOR
Ensure that the 5-15 psig nitrogen charge is maintained
with 15 psig preferred.
Rotate the male rotor shaft every two weeks. Mark the
shaft to ensure the rotor does not return to the original
position.
The compressor must be stored inside a dry building
environment.
Grease the male rotor shaft to prevent rust.
Record all information in a “Compressor Long Term Storage
Log.” See bottom of page 4.
Contact Johnson Controls-Frick Service with any
questions regarding long term storage.
DESCRIPTION
FRICK 408 MM COMPRESSOR
The Frick 408 mm rotary screw compressor utilizes mating
asymmetrical profile helical rotors to provide a continuous
flow of vapor and is designed for both high-pressure and
low-pressure applications. The compressor incorporates
the following features:
1. High-capacity roller bearings to carry radial loads at
both the inlet and outlet ends of the compressor.
2. Heavy-duty, angular-contact bearings are mounted at
the discharge end of the compressor to carry axial loads.
3. Balance pistons, located in the inlet end of the
compressor, reduce axial loads on the male axial bearings
to increase bearing life.
4. Moveable slide valve to provide fully modulating capacity
control from 100% to approximately 15% (condition
dependent) of full load capacity.
5. VOLUMIZER volume ratio control to allow infinitely
variable volume ratio from 2.2 to 5.0 for all 408 mm models
(except the 408XL: Vi = 2.2 – 4.3) during compressor
operation.
6. A hydraulic cylinder to operate the slide stop and slide
valve.
7. Housings are designed for 600 psig pressure.
8. Shaft seal housing is designed to maintain operating
pressure on seal well below discharge pressure for increased
seal life.
9. Oil injected into the rotors to maintain good volumetric
and adiabatic efficiency even at very high compression
ratios.
10. Shaft rotation clockwise facing compressor, suitable for
all types of drives.
SEE FOLLOWING WARNING.
WARNING
Compressor rotation is clockwise when facing the
compressor drive shaft. The compressor should never
be operated in reverse rotation, as bearing damage
will result.
11. Suction and discharge flanges are ANSI B16.1 Class 300
for all models.
12. The 408 mm compressors must be fitted with a suitable
strainer, #60 mesh X .0065” diameter stainless steel wire or
better, to prevent damage to the compressor from particles
entering the suction area.
COMPRESSOR LUBRICATION SYSTEM
The lubrication system on a 408 mm screw compressor
performs several functions:
1. Provides lubrication to bearings and seal.
2. Provides a cushion between the rotors to minimize
noise and vibrations.
3. Helps keep the compressor cool and prevents
overheating.
4. Provides an oil supply to hydraulically actuate the slide
valve and slide stop.
5. Provides oil pressure to the balance piston to help
increase bearing life.
6. Provides an oil seal between the rotors to prevent rotor
contact or gas bypassing.
BALANCE PISTON PRESSURE REGULATION
Axial bearing loads and life are determined by the oil
pressure supplied to the balance piston. The 408 compressor
will require balance piston oil pressure regulation. Refer to
CES 6605 for a standard system and CES 6607 for guidelines
in how to determine the acceptability of a standard system
or the need for a custom regulator.
BALANCE PISTON OIL PUMP BOOST
An oil pump boost to the balance piston (SB-2) may be
required to maintain acceptable axial bearing life. CoolWare
will provide a warning if an oil pump is required.
Refer to CES 6606 for basic oil pump requirements and
basic piping diagrams. Actual system operating conditions
may necessitate the need for piping systems other than
those addressed by CES 6606. Contact Johnson Controls-
Frick Service for assistance.
CONTROL OIL PUMP
The 408 mm Compressor incorporates a slide valve to
regulate compressor loading and a Slide Stop to control
