ANGI ENERGY SYSTEMS CNG User manual

JUNE 2006
OPERATION AND
MAINTENANCE MANUAL
ELECTRIC MOTOR DRIVE ARIEL
CNG COMPRESSOR STATION

NOTICE
IMPORTANT SAFETY INFORMATION
Only operate this equipment in accordance with the instructions provided
in this manual. Improper operation of this equipment could cause serious
bodily harm or death and will void the equipment warranty.
Repair or maintenance of this equipment should only be completed by
ANGI Customer Service personnel or the Customer’s qualified service
representative.
Should you detect a gas leak…
1. Immediately shut down the compressor and leave the compressor
station.
2. Extinguish any open flame or source of ignition.
3. Shut off the supply valve and contact your authorized ANGI service
representative and/or gas supplier.

ANGI NATURAL GAS COMPRESSOR STATION
ELECTRIC MOTOR DRIVE, ARIEL PACKAGE
TABLE OF CONTENTS
USER MODIFICATIONS..................................................................................................................4
1. INTRODUCTION..........................................................................................................................5
2. DESCRIPTION.............................................................................................................................5
2.1 COMPRESSOR............................................................................................................5
2.2 GAS SYSTEM............................................................................................................5-6
2.3 DRIVER.........................................................................................................................6
2.4 CONTROLSAND INSTRUMENTATION ...................................................................6-7
3. COMPRESSOR SAFETY............................................................................................................8
3.1 GENERAL SYNOPSIS..................................................................................................8
3.2 OPERATING .................................................................................................................8
3.3 SERVICING ...............................................................................................................8-9
3.4 LIFTING/TIE DOWN .....................................................................................................9
4. INSTALLATION..........................................................................................................................10
4.1 UNPACKING AND HANDLING...................................................................................10
4.2 SITE REQUIREMENTS..............................................................................................10
4.3 STORAGE...................................................................................................................10
5. OPERATION .............................................................................................................................. 11
5.1 INITIAL START UP...................................................................................................... 11
6. MAINTENANCE.........................................................................................................................12
6.1 RECOMMENDED PREVENTATIVE MAINTENANCE SCHEDULE...........................12
6.2 SERVICE SPECIFICATION...................................................................................12-13
7. TROUBLESHOOTING...............................................................................................................14
8. APPENDIX .....................................................................................................................................
8.1. PREVENTIVE MAINTENANCE SCHEDULE ............................................................15

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
USER MODIFICATION
ANGI must authorize all modifications to this
equipment. Any unauthorized modifications will
void the warranty, may cause damage to the
equipment and could cause bodily harm.
DISCLAIMER
ANGI disclaims any responsibilities whatsoever to
the customer or to any person for injury or damage
to or loss of property or value resulting from the
use of its products which have been subjected to
misuse, accidents, misapplied, repaired by
unauthorized person, or improperly installed.
NOTICE: This manual is as current as possible at
the time of printing and is subject to change
without notice. For information not covered in this
manual, consult ANGI.
CONTRACTOR OR INSTALLER: Leave this
manual with the compressor station after
installation is complete.
CUSTOMER: Retain this manual for future
reference.

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
1. INTRODUCTION
This manual is intended to assist in the operation
and maintenance of ANGI compressed natural gas
(CNG) compressors used in CNG vehicle re-
fueling applications.
ANGI Compressor Stations are designed for
continuous duty and unattended operation when
properly applied and serviced. This compressor
station is designed to compress natural gas to
desired discharge pressure. The compressor,
manufactured by Ariel Corporation, is a lubricated,
multi-stage, horizontally opposed, balanced,
reciprocating compressor.
An electric motor drives the compressor by means
of a direct coupling. The compressor package
includes forced-air inter-coolers and after-cooler to
cool the process gas between each stage of
compression and prior to discharge, relief valves,
and particulate and coalescing filters and priority
storage valves.
The compressor station is delivered with a control
system to provide automated compressor
operation, shut down limit monitoring and fault
annunciation.
The machine is designed and manufactured to
conform to NFPA 52 for Compressed Natural
Gas (CNG) Vehicular Fuel Systems and the
National Electrical Code ANSI/NFPA 70.
2. DESCRIPTION
2.1 COMPRESSOR
The compressor station utilizes an Ariel
compressor frame configured with specific
cylinders, pistons, and valve components sized to
provide the gas delivery performance required for
this application. Full details on the Ariel
compressor used in this application may be found
in the Ariel manuals provided with this machine.
Integral to the compressor is a chain driven frame
lube pump and filter system, a separate force feed
lube and manifold system to distribute lubricant to
the lube points for the packing seals and rings and
a venting system. The oil is cooled by means of a
remote oil cooler. An optional oil immersion heater
is used to maintain a minimum oil temperature in
cold service environments.
2.2 GAS SYSTEM
The gas system can be divided into the
induction system, compressing system, re-
circulation system.
2.2.1 Induction System
Gas is delivered to the station by a user-
supplied connection. If it is possible for the inlet
gas pressure to rise above the specified inlet
pressure, then the user must provide an inlet
regulator to restrict the inlet pressure to a value
within the limits of the machine. The control
system monitors the inlet gas pressure and will
shut down the compressor if the inlet gas is not
provided within the allowable pressure range.
The shut down levels for the inlet gas pressure
have been set for the proper operating pressure
range and should not be adjusted in the field.
Gas is also re-introduced into the inlet of the
compressor from the captive recovery tank
located on the skid. An on-skid regulator is
provided to regulate the pressure of the re-
circulated gas to match the specified inlet gas
pressure. By re-circulating the gas in this
fashion, the gas from the compressor blow-down
process is recovered.
An actuated inlet valve is provided on-skid to
interrupt gas flow to the compressor. This valve
is only open when the compressor running in
loaded operation and during the warm-up and
cool down cycle. This valve remains closed
when the compressor is off or in stand-by.
An inlet filter is provided to trap any incoming
particulate and minor slugs of water or oil from
the captive recovery tank. The bowl on this filter
is provided with a sight gauge to determine if the
filter should be drained.
The inlet piping is provided with a safety relief
valve to prevent over-pressurization due to
failure of one of the pressure regulators or 1st
stage compressor valves.
2.2.2 Compressing System
This portion of the system contains the
reciprocating compressor, safety relief valves,
inter-stage filtration, inter-stage cooling and after
cooling. The gas is compressed to the specified
discharge pressure in multiple stages of
compression.
Between each stage of compression, the gas is
passed through air-cooled fin and tube heat
exchangers to be cooled. The heat exchangers
and fan system have been sized to meet the
application.

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
After cooling, the gas is past through a filter to
remove any condensed liquids and to reduce the
amount of oil introduced into the gas stream by the
compressor.
At the discharge of each stage of compression, the
gas temperature and pressure is monitored
against shutdown limits and the compressor will
shutdown should any inter-stage pressure or
temperature trend outside of the operational limits.
Exiting the final stage of compression, the gas is
passed through an air-cooled, fin and tube heat
exchanger for after-cooling. The after-cooler and
cooling fan have been sized to meet the
application.
The gas is then passed through a pre-coalescing
filter and a coalescing filter to remove oil from the
gas stream prior to delivery to the storage system
or dispenser.
After the final stage filtration, the discharge
pressure is monitored by the control system
against START and STOP limits to determine if the
compressor should resume, continue or stop
compressing gas.
Safety relief valves are provided on each stage of
the compressor discharge piping to prevent
dangerous over-pressurization due to compressor
valve failure, flow blockage or control system
failure.
2.2.3 Re-circulation System
Tubing lines and valves are installed between the
inter-stage and discharge filter bowls and the
captive receiver tank. At pre-determined intervals
of operation and during warm-up and cool-down
sequences, the gas is allowed to flow from the
discharge of the compressor stages, through the
filter bowls and into the receiver tank. During this
time, the compressor is effectively operating
unloaded and, consequently, allows for smooth
compressor starts and stops. This system also
allows for automatic purging of the filter bowls of
accumulated liquids.
2.3.COMPRESSOR AND FAN DRIVER
An electric motor rated for the application is used
to drive the compressor. The motor has been
sized for this application and has adequate power
to drive the compressor with ample reserve power
to maintain a continuous duty rating. A smaller
secondary motor is provided to drive the cooler
fan.
Amotor starter starts the compressor motor.
Inside the motor starter enclosure is a motor
contractor for starting the fan motor. The motors
are started and stopped automatically based on
control signals sent to the motor starters from
the control system.
2.4 CONTROLS AND INSTRUMENTATION
2.4.1 Control System
This compressor station is delivered with a PLC
based control system. The control system
provides all the compressor controls and
monitoring function required to allow fully
automatic, unattended operation and to provide
fault code annunciation for quick fault recovery.
For additional technical information on the
control system refer to the control system
operations manual and the electrical drawing
package included in this manual.
2.4.1.1 Modes of Operation
With power supplied to the station and the
ON/OFF keyswitch placed in the ON position,
the control system is capable of supporting five
modes of operation. These modes of operation
are;
1) STAND-BY
In this mode the storage is considered to be full
and the compressor is stopped. The control
system monitors the discharge pressure against
a START pressure limit. The compressor will
remain in this mode until the storage is depleted
below this START pressure limit.
2) WARM-UP
Once the control system detects that the gas
storage has been emptied below the START
pressure limit, the pre-lube pump runs for a
period of time, the inlet valve opens, the fan
motor is started and runs and then the
compressor drive motor is started and runs.
During this warm-up period the load/recirculation
valve is open so that gas is simply re-circulated
through the captive receiver tank.
3) COMPRESSION
After the completion of the warm-up cycle, the
control system switches to loaded compressor
operation. During the transition from warm-up
mode, the fan and compressor motors remain
on and the load/recirculation valve is closed so
that gas flows into to the discharge piping.
During longer, uninterrupted operation in this
mode, the load/recirculation valve will open
during pre-determined intervals to drain the filter
bowls of accumulated fluids. The control system

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
will continue to run in this mode until the discharge
pressure reaches the STOP pressure set point
defined in the controller (or the compressor faults)
4) COOL-DOWN
Once the controller determines that the storage
pressure is above the STOP pressure set-point,
the load/recirculation valve opens and the
compressor motor and fan motor continue to run
for a period of time to allow the compressor to
unload and cool. After a cool down timer expires,
the fan and compressor motors are stopped and
the control system returns to STAND-BY mode.
5) FAULTED
During any of the modes mentioned above, the
control system may detect a shutdown condition
and the machine will be placed in FAULTED mode.
In this mode the suction valve is closed and the
fan and compressor motor is stopped. The nature
of the fault is announced on the front panel of the
control enclosure.
2.4.1.2 Fault Conditions
A number of digital inputs and analog transducers
are monitored by the control system to initiate a
machine shutdown due to faulted operation.
Only a subset of all the inputs and transducers are
monitored for fault conditions in any one of the
possible modes of operation. For example, the
compressor oil pressure reading is ignored during
STAND-BY operation.
The fault tables below identify possible fault
conditions.
DIGITAL FAULTS
DESCRIPTION
Keyswitch
Reset
Oil Level Low
High Vibration
Low Oil Flow – Compressor
High Final Pressure
Emergency Stop Activated
High Liquid Level – Receiver
High Lube Temp – Compressor
Too Many Starts Per Hour
Note: An Emergency Stop Fault is an indication
that either a remote or local E-Stop pushbutton
has been depressed (or a rate of rise heat
detector has detected a fire or the gas detector
has detected a gas leak).
HIGH ANALOG FAULTS
DESCRIPTION
High Suction Pressure
High Receiver Pressure
High Final Pressure
High 1st Stage Pressure
High 2nd Stage Pressure
High 3rd Stage Pressure
High 4th Stage Pressure
High Oil Pressure – Compressor
High 1st Stage Temperature
High 2nd Stage Temperature
High 3rd Stage Temperature
High 4th Stage Temperature
LOW ANALOG FAULTS
DESCRIPTION
Low Suction Pressure
Low Receiver Pressure
Low Final Pressure
Low 1st Stage Pressure
Low 2nd Stage Pressure
Low 3rd Stage Pressure
Low 4th Stage Pressure
Low Oil Pressure – Compressor
Low 1st Stage Temperature
Low 2nd Stage Temperature
Low 3rd Stage Temperature
Low 4th Stage Temperature

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
3. COMPRESSOR SAFETY
3.1 GENERAL SYNOPSIS
ANGI designs and manufactures all its products
for safe operation. However, the responsibility for
safe operation rests with those who use and
maintain these products. The following safety
precautions are offered as a guide, which, if
followed, will minimize the possibility of accidents
throughout the useful life of this equipment.
Only those delegated individuals who have read
and understand the operator’s manual and have
satisfactorily completed the ANGI training should
operate this CNG compressor station. Failure to
follow the instructions, procedures and safety
precautions in this manual may increase the
possibility of accidents and injuries.
Never start this CNG compressor station unless it
is safe to do so. Do not attempt to operate the
CNG compressor station with a known unsafe
condition. Lock Out / Tag Out the compressor
station to render it inoperative so others who do
not know of the unsafe condition will not attempt to
operate the unit until the unsafe condition has
been corrected.
Never clean, adjust or repair this machinery while
it is in an operating state. To reduce the risk of
injury while performing service follow the
instructions in the manual for placing the CNG
compressor station in a zero energy state.
Use and operate this CNG compressor only in full
compliance with all pertinent OSHA requirements
and pertinent federal, state and local code
requirements.
Do not modify this CNG compressor station except
with written factory approval.
3.2 OPERATING
3.2.1 Before You Start the Compressor
* Assure that there are no obstructions near
the enclosure that may restrict ventilation
flow.
* Check fluid levels
* Check for any signs of fluid leaks on the
floor/ground.
* Remove all tools and/or loose items from the
equipment.
* Verify that the inlet gas pressure does not
exceed allowable limits of this machinery.
* Verify that all guards are in place
* Verify that all sources of ignition are
extinguished.
* Verify that authorized personnel have
satisfactorily completed all scheduled
maintenance tasks.
* Verify that all valves between compressor
discharge and storage are open.
3.2.2 Use of Compressor Station
* Do not wear loose clothing around the
machinery.
* Do not operate the equipment with loose,
broken or out of balance fan blades.
* Do not operate the equipment with a
known gas leak.
* Routinely (daily) monitor and record all
gauge pressures as part of your predictive
maintenance program.
3.2.3 Other Safety Precautions
* Do not touch hot surfaces or moving parts,
such as exhaust or fans.
* Do not adjust or restrict relief valves.
* Do not disconnect or alter shutdown
sensors or switches.
* Be aware of hot surfaces, sharp corners
and edges.
3.3 SERVICING
* Before servicing this compressor station,
place the station in a zero energy
condition in accordance with the
instructions below.
* Make repairs only in clean, dry, well-lighted
and well-ventilated areas. Keep all parts
of the body and any hand held tools or
other metal objects away from exposed
live parts of the electrical system.
3.3.1 Zero Energy Condition
To minimize the risk of injury or accident during
servicing, these procedures should be followed
to place the station in a zero energy state.
CAUTION! ELEVATED PRESSURES WILL
STILL EXIST IN PORTIONS OF THE
COMPRESSOR STATION PIPING AFTER
PERFORMING THESE PROCEDURES.
1) Using your companies approved Lock Out /
Tag Out procedures, disconnect the three
phase electrical voltage and the control
voltage. Consult site drawings for the
location.
2) Using approved Lock Out / Tag Out
procedures, turn off the main inlet gas valve.
3) Using approved Lock Out / Tag Out
procedures, turn off the isolation valves on
the storage cascade. Consult site drawings
for the location.

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
4) Insure there is no source of ignition near or
down wind of the compressor station.
5) Open the manual ball valve, located near the
final compressor stage relief valve, in the final
stage discharge line to vent discharge line
gas.
6) Open the manual ball valve on the captive
receiver tank to vent the gas in the tank.
Failure to heed any of the above warnings or
misuse of the compressor, even though not
expressly mentioned herein, may result in
severe injury or death, property damage and/or
mechanical failure for which ANGI will not be
held responsible.
3.4 LIFTING/TIE DOWN
The compressor station will be provided with four
lifting eyes on the outside corners of the station or
it will be supplied with four overhead lifting eyes. If
overhead lifting eyes are provided, use them
instead of the 4 corner lift points to eliminate the
requirement for the long spreader bar and to
reduce the occurrence of damage to the
compressor enclosure.
If there are any question regarding lifting, tie
down or securing this equipment, contact
ANGI prior moving this equipment.
Only designated personnel shall do the lifting.
The load capacity rating shall be clearly
marked on hoist. Do not exceed load rating.
Inspection and testing for cracks or defects in
hoist system shall be performed on a regular
basis. Before lifting, alert personnel in
immediate areas. Do not stand under unit while
it is being moved from one area to another on
a hoist. Do not stand under unit to do
maintenance work.
Lifting eyes are positioned to provide safe
lifting and/or tie down and must be used
properly. Secure or lift using all rings at all
times. Secure at approved tie down points
only. Failure to follow proper procedures can
result in damage to equipment and injury to
personnel.

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ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
4. INSTALLATION
4.1 UNPACKING AND HANDLING
Occasionally, damage may occur during shipping.
Be sure to carefully inspect the unit before and
after unpacking. If damage has occurred, contact
the freight carrier and file the appropriate claim
forms. Then inform your ANGI representative
immediately.
Your compressor station has been prepared for
shipping at ANGI’s factory. This preparation
requires disassembly of some of the station
components. Re-assembly at the site is to be
completed with proper instruction or supervision of
the ANGI service representative.
4.2 SITE REQUIREMENTS
Installation is only to be completed with the
direct involvement of an authorized ANGI
customer service representative or with full
installation drawings present at the installation
site. Do not attempt to install this equipment
without these resources.
During installation, should any discrepancy be
found between the actual machinery and the
machine prints or site drawing, immediately
notify the installation coordinator and the ANGI
customer service representative.
4.2.1 Foundation
Your ANGI compressor station should be installed
on a level pad of 8 inch (minimum thickness)
reinforced concrete. The compressor station
should not be operated prior to being secured to
the concrete pad.
4.2.2 Gas Supply
CAUTION! THE INDUCTION MUST NEVER BE
ALLOWED TO FLOAT HIGHER THAN THE
SPECIFED MAXIMUM INDUCTION PRESSURE.
MACHINE DAMAGE MAY RESULT.
The volume of gas required is dependent on
induction pressure and discharge pressure
conditions.
4.2.3 High Pressure Gas Connections
High-pressure discharge lines between the
compressor station and the storage and/or
dispenser(s) are typically connected by qualified
contractors or by an ANGI authorized customer
service representative. Consult the site diagrams
and the on-site ANGI representative prior to
making these connections.
4.2.4 Electrical Connections
High voltage connections are to be made only
by a qualified electrician, in accordance with the
ANGI interconnection diagrams.
Each of the following connections is required
between the compressor station and the site’s
control and power distribution center:
1) Grounding connections
2) Control power lines
3) Control signal wires
4) Infallible ground connection
5) ESD wiring
6) Telephone wiring (If required)
Verify that each of these connections have been
made as specified on ANGI’s interconnection
diagrams.
4.3 STORAGE
In some cases it may be necessary to store the
compressor for extended periods of time before
placing the unit in operation:
1) Place the station in a zero energy condition
in accordance with the instructions provided
in this manual.
2) Cover and seal all machine openings to
prevent the entrance of water and dirt.
3) If the storage conditions are below freezing,
make sure any moisture is drained off
aftercoolers, traps, water-cooled heat
exchangers and attendant piping.
4) Cover with a waterproof tarpaulin that can
be easily removed for in-storage
maintenance.
5) Place a fresh desiccant package in the
control enclosure and in the on skid motor
starter enclosure (if supplied)
6) Compressor cylinders, valves, valve
pockets, cross-head guides and the inside of
the cylinder lube pump box should be
coated with a polar anti-seize/anti-rust agent
such as Mobil Oil Corporation, Mobilarma
No. 246.
7) Pour 3 ounces of liquid vapor corrosion
inhibitor such as Corroless 300 into the
crankcase.
8) Every two or three months, manually crank
the compressor motor over one turn plus 90
degrees to prevent flat spots on the bearings
that could lead to premature failure.
At the end of the storage period, follow the
uncrating and start up procedures. If the unit
has been stored for an extended period, contact
ANGI before restarting the compressor.

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5. OPERATION
5.1 INITIAL START UP
IMPORTANT! READ ARIEL CORPORATION’S
SERVICE MANUAL AND COMPLETE THE
ARIEL START-UP CHECK LIST.
1) Verify that all scheduled installation tasks have
been completed and inspected and all
auxiliary equipment is prepared.
2) Complete the Ariel Compressor Start Up
Check List in entirety
3) Inspect fan blades to insure they are not
missing, cracked or otherwise damaged.
4) Verify all belts are in place and properly
tensioned and guards are in place and that
they do not interfere with rotating equipment.
5) Verify that all safety devices and Emergency
Stop circuits are functional.
6) Verify inlet pressure is correct.
7) Verify all electrical connections to the motor
starter are properly made.
8) Verify that all personnel are at a clear and safe
distance from the machine and have been
instructed that the machine is to be started.
9) When ready to start, apply power to the station
and place the ON/OFF keyswitch in the ON
position.
10) Observe that the fan motor starts smoothly
without lugging and without belt slippage.
11) Observe that the compressor motor starts
smoothly without lugging and absent of harsh
vibrations and noises.
12) Verify that the compressor crankcase
develops oil pressure and that the indicator pin
is moving on the compressor lubrication
distribution block.
13) Observe that there are no excessive vibrations
or unusual noises.
14) Check for any gas leaks.
15) Check for any oil leaks.
16) Monitor and record inter-stage and discharge
pressures.

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6. MAINTENANCE
6.1 RECOMMENDED PREVENTATIVE
MAINTENANCE SCHEDULE
ANGI has developed a preventative maintenance
schedule for this equipment based on number of
hours of operation. Adhering to this schedule will
minimize unscheduled downtime and assure long
machine life.
This maintenance schedule is summarized in the
Preventative Maintenance Table included in the
Appendix in this section. The maintenance
intervals in this table are based on the hours of
operation displayed on the control panel hour
meter. When using this table, refer to the Service
Specifications in this manual for detailed servicing
procedures and considerations.
This table has been set-up based on nominal
operating conditions and will need to be
altered for harsh operating environments.
When performing any maintenance, lock out
the controls to prevent inadvertent starting.
6.2 SERVICE SPECIFICATIONS
6.2.1 COMPRESSOR CRANKCASE LUBE
SYSTEM
6.2.1.1. Compressor Lubrication Spec.
See Compressor Operation & Maintenance
Manual for the correct lubrication specifications.
The compressor is shipped with Polyglycol
lubricant in the crankcase on all North
American orders. DO NOT MIX with Petroleum
based oils.
International shipments have diester synthetic
oil in the crankcase. Diester synthetic will mix
with petroleum oils.
6.2.1.2. Compressor Crankcase Lube Level
A sight glass is provided on the auxiliary end of the
crankcase that identifies the lubrication level. The
oil should always be replenished by removing the
breather cap and adding oil through the top cover.
DO NOT ADD OIL WHILE THE COMPRESSOR
IS RUNNING
The oil level should be filled 2/3-3/4 of the sight
glass. DO NOT OVERFILL THE CRANKCASE
SUMP. After running the compressor, it may be
necessary to add oil to the crankcase sump to
one-half level on the sight gauge, but never must
exceed two-thirds height when the compressor is
primed and running.
Assure that the system has been fully primed
prior to checking oil levels.
6.2.1.3. Compressor Crankcase Oil Pressure
A spring loaded oil pressure regulator is
provided on the compressor. The oil pressure
may be adjusted by removing the cover on the
regulator and turning the adjusting bolt. The oil
pressure has been set by ANGI to the proper
operating pressure of 55-60 psig as measured
on the downstream side of the oil filter.
6.2.1.4. Compressor Crankcase Oil Filtration
A strainer basket and oil filter is provided to
provide filtration. Always replace the oil filter
element and clean the strainer basket when
replacing the crankcase oil.
The strainer basket is located on the auxiliary
end of the compressor frame below the oil level.
Only the replace filter element with a same
grade element. Element replacement interval
should be completed per the Periodic
Maintenance Schedule or any time a 10 psig
pressure drop is detected across the filter.
6.2.2. COMPRESSOR FORCED FEED
LUBRICATION SYSTEM
6.2.2.1. Lubrication Reservoir Level
A separate lubrication reservoir and sight glass
is provided to lubricate the worm gear and cam
on the lubricator.
6.2.2.2. Lubrication Rate
The lubrication feed rate may be adjusted by
turning an adjuster knob on top of the lubricator.
Proper lubrication rate may be confirmed by
observing the indication on the digital no-flow
switch. This switch is mounted to the lubrication
distribution block. Verify that the lubrication rate
by observing the indication and comparing the
rate to that specified on data plate attached to
the lubricator.
6.2.3. COOLING SYSTEM
6.2.3.1 Cooling Fan
The fan blade should be inspected for cracked
or broken blades. Additionally, the blade pitch
should be uniform between blades. Verify that
the fan is not rubbing on the bell or on any fan
guarding.
Never operate the station with missing or
damaged fan blades or without the fan blades
properly installed.

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6.2.3.2 Gas Cooler Cores
Inspect coolers for loose inlet and discharge
clamps, leaks and debris caught in the cooler fins.
Clear all debris from cooler fins and/or cooler
levers to assure full, unrestricted air flow is
permitted across the entire cooler face.
6.2.5. MONITORING & REPORTING GAUGE
PRESSURES AND TEMPERATURES
Recording and charting of gauge pressures and
gauge temperatures can help identify a developing
compressor problem before downtime or damage
results.
ANGI recommends that all gauge temperatures
and pressures be recorded on a daily basis and
charted for trends. Be sure to also record time of
day, ambient temperature and any other
environmental condition that may influence gauge
readings.
6.2.4. RECEIVER TANK
Fluids filtered from the filter bowls are
automatically drained and will collect in the
receiver tank. Therefore, the receiver tank should
be drained periodically. To drain the receiver tank,
slowly open the manual valve located on the drain
piping exiting the bottom of the receiver tank.
A high liquid level switch is provided in the receiver
tank to fault the station should the liquid level
become to high.
6.2.5. COMPRESSOR VALVES
This compressor is equipped with premium
compressor valves manufactured by the Hoerbiger
Corporation.
Compressor valves require periodic inspection,
cleaning and rebuild. These operations should be
performed per instructions provided in the
Hoerbiger service manual and the Ariel
compressor service manual included with this
manual.
Careful attention must be paid to component
orientation and assembly sequence. When
replacing springs, use replacement springs with
identical springing valves.
6.2.6. FILTERS AND OIL SEPARATORS
6.2.6.1 Inlet Filter
An inlet filter is provided to keep particulate
material and minor slugs of water and oil out of
the compression system. This filter is equipped
with sight gage to indicate if any amount of liquid
is accumulating in the filter bowl.
If liquid has collected in the bowl, drain the filter
bowl using the manual service valve at the
bottom of the filter bowl.
Since this filter has only limited capacity to
protect the compressor from damage due to
liquid in the gas stream, any observance of
liquid in the filter bowl should be investigated. If
an inlet gas dryer is used in the process it may
need to be serviced. If no dryer is present, one
may need to be added.
The inlet filter has a replaceable or washable
filter element installed. This element needs to be
changed or cleaned at the prescribed service
interval.
6.2.6.2 Coalescing Filters
Inter-stage and final discharge coalescing filters
are provided to control oil introduced into the
gas by the compression process and to
eliminate in liquids which may have condensed
out of the gas stream during compression.
The inter-stage filters utilize removable fine
mesh strainer elements that may be cleaned
and re-used. These elements should be pulled
out of the filter housing for inspection and
cleaning at the prescribed service interval. If
any portion of the element appears damaged or
stressed, then replace the element with a new
one. Inspect the sealing o-ring on the element
holder and the housing cover to assure it has
not been damaged. Use care not the damage
the seals when re-installing the element and
element holder.
The final filters utilize replaceable filter elements
that should be replaced at intervals prescribed
on the periodic maintenance schedule. When
replacing these elements, assure they are
properly mounted in the filter assembly and use
caution not to cut or damage pressure-sealing o-
rings on the filter.

14
ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
7. TROUBLESHOOTING
1. Low Compressor Oil Pressures
A. Check the oil level
B. Check/Replace oil filter element
C. Clean oil strainer bowl
D. Check for oil leak
E. Check for defective pressure switch
F. Check/Adjust oil pressure reg. setting
G. Check oil pressure pump
H. Check 3 phase circuit breaker/fuses
2. High Discharge Temperature
A. Check for failed compressor valve
B. Check cooler fins for debris
C. Check cooler fan.
D. Check for high discharge temperature
E. Compare RTD reading to thermometer
reading to verify RTD function
3. High Inlet Pressure
A. Check induction regulator setting (off
skid)
B. Check receiver tank discharge regulator
setting
4. High Discharge Pressure
A. Check compressor valves
B. Check for blockage in discharge piping
5. Low Discharge Pressure
A. Check for low induction pressure
B. Check for leaks
C. Check valves
D. Check for restrictions in inlet
E. Check/Replace Filter Elements
6. Low Flow Capacity
A. Check for leaks
B. Check for low induction pressure
C. Check for proper driver rpm
D. Check compressor valves
E. Inspect compressor piston rings
8. Unit Shuts Down After Start Sequence
A. Read fault indications
B. Verify that the motor starter did not
overload
9. High Oil Carry-over In Discharge Gas
A. Check/Replace inter-stage & final filters
B. Verify operation of automatic drain
sequence
C. Check for proper crankcase lube level
D. Verify force-feed lube rate
E. Check compressor inlet valves
10. High Lube Temp – Compressor
A. Clear any debris from oil cooler
B. Check/Replace oil filter element
C. Change oil if required.
11. High Receiver Tank Pressure
A. Verify receiver discharge reg. setting
B. Make sure liquid level float switch is
functioning and the receiver tank is
drained
C. Check discharge check valve for
leakage
12. Hi/Low Analog Temperature Readings
On Several Channels
A. Verify that DC power supply in the
control panel is delivering 24.0 VDC
B. Replace or swap analog input card
13. Hi/Low Analog Temperature Readings
on a Single Channel
A. Check wiring between A/D card and
barrier and between barrier and
traducer.
B. Replace transmitter or RTD
C. Replace input barrier

15
ANGI OPERATION AND SERVICE MANUAL Rev 2006/06
APPENDIX 1. Preventive Maintenance Schedule
Maintenance Levels Level 1 Level 2 Level 3 Level 4 Level 5
Operation Interval Daily Monthly Every 2000
Hours Of
Operation
Every
4000
Hours Of
Operation
Every
8000
Hours Of
Operation
Shutdown Required Yes Yes Yes Yes Yes
Item
Service Item
1 Monitor & Record Working Pressures and Temperatures 9
2 Check Compressor, Piping and Tubing For Obvious Leaks, Loose
Connections or Loose Clamps
9
3 Check For Rough/Unusual Noises 9
4 Check Compressor Oil Level 9
5 Drain Receiver Tank If Required 9
6 Drain Condensate Pot 9
7 Change Compressor Oil & Filter And Clean Strainer
9
8 Clean Inter-stage Stage Filter Elements and Replace Final Filter Elements
and Inlet Filter Elements
9
9 Inspect Safety Relief Valves 9
10 Inspect Compressor Valves
9
11 Inspect Compressor Rings and Seals
9
12 Verify Driver / Compressor Alignment
9
13 Inspect Compressor Crank Shaft Main & Rod Bearings
9
14 Inspect Compressor Lub. Drive Chain
9
15 Drain and Clean Heat Exchanger Cores
9