Gardner Denver AUTO SENTRY EAU99G Service manual

GARDNER DENVER®
13-10-614
Version: 04
October 29, 2003
ELECTRA-SAVER
STATIONARY BASE-MOUNTED
COMPRESSOR
AUTO SENTRY-- ES+ CONTROLS
DOMESTIC MODELS
EAU99G & M – 200, 250 & 300 HP
INTERNATIONAL MODEL
EAU99H – 150, 186 & 225 KW
OPERATING AND
SERVICE MANUAL

13-10-614 Page ii
MAINTAIN COMPRESSOR RELIABILITY AND PERFORMANCE WITH
GENUINE GARDNER DENVER® COMPRESSOR PARTS AND SUPPORT SERVICES
Gardner Denver® Compressor genuine parts, manufactured to design tolerances, are developed for optimum
dependability – specifically for Gardner Denver compressor systems. Design and material innovations are the result
of years of experience with hundreds of different compressor applications. Reliability in materials and quality
assurance is incorporated in our genuine replacement parts.
Your authorized Gardner Denver Compressor distributor offers all the backup you’ll need. A worldwide network of
authorized distributors provides the finest product support in the air compressor industry. Your local authorized
distributor maintains a large inventory of genuine parts and he is backed up for emergency parts by direct access to
the Master Distribution Center (MDC) in Memphis, Tennessee.
Your authorized distributor can support your Gardner Denver air compressor with these services:
1. Trained parts specialists to assist you in selecting the correct replacement parts.
2. Factory warranted new and remanufactured rotary screw airends. Most popular model remanufactured airends
are maintained in stock at the Remanufacturing Center in Indianapolis, IN., for purchase on an exchange basis
with liberal core credit available for the replacement unit.
3. A full line of factory tested AEON™ compressor lubricants specifically formulated for use in Gardner Denver
compressors.
4. Repair and maintenance kits designed with the necessary parts to simplify servicing your compressor.
Authorized distributor service technicians are factory trained and skilled in compressor maintenance and repair. They
are ready to respond and assist you by providing fast, expert maintenance and repair services.
For the location of your local authorized Gardner Denver Air Compressor distributor, refer to the yellow
pages of your phone directory or contact:
Distribution Center: Factory:
Gardner Denver
Master Distribution Center
5585 East Shelby Drive
Memphis, TN 38141
Gardner Denver
1800 Gardner Expressway
Quincy, IL 62301
Phone: [phone]
[phone] Phone: [phone]
Fax: [phone] Fax: [phone]
INSTRUCTIONS FOR ORDERING REPAIR PARTS
When ordering parts, specify Compressor MODEL, Method of Cooling, HORSEPOWER and SERIAL NUMBER (see
nameplate on unit). The Serial Number is also stamped on top of the discharge bearing carrier casting.
All orders for Parts should be placed with the nearest authorized distributor.
Where NOT specified, quantity of parts required per compressor or unit is one (1); where more than one is required
per unit, quantity is indicated in parenthesis. SPECIFY EXACTLY THE NUMBER OF PARTS REQUIRED.
DO NOT ORDER BY SETS OR GROUPS.
To determine the Right-Hand and Left-Hand side of a compressor, stand at the motor end and look toward the
compressor. Right-Hand and Left- Hand are indicated in parenthesis following the part name, i.e. (RH) and (LH),
when appropriate.

13-10-614 Page iii
FOREWORD
Gardner Denver Rotary Screw compressors are the result of advanced engineering and skilled
manufacturing. To be assured of receiving maximum service from this machine the owner must exercise
care in its operation and maintenance. This book is written to give the operator and maintenance
department essential information for day-to-day operation, maintenance and adjustment. Careful
adherence to these instructions will result in economical operation and minimum downtime.
DANGER
Danger is used to indicate the presence of a hazard which will cause severe
personal injury, death, or substantial property damage if the warning is ignored.
WARNING
Warning is used to indicate the presence of a hazard which can cause severe
personal injury, death, or substantial property damage if the warning is ignored.
CAUTION
Caution is used to indicate the presence of a hazard which will or can cause
minor personal injury or property damage if the warning is ignored.
NOTICE
Notice is used to notify people of installation, operation or maintenance
information which is important but not hazard-related.
This book covers the following models:
HP PSIG Air Cooled and
Water Cooled Parts List Controller Manual
200, 250, 300 100, 125, 150 EAU99G 13-10-512 13-9-653
200, 250, 300 100, 125, 150 EAU99M 13-10-517 13-9-653
HP
(Kw) PSIG (Bar) Air Cooled and Water Cooled Parts List Controller Manual
200, 250, 300
(150, 186, 225)
100, 125, 150
(6.9, 8.6, 10.3) EAU99H 13-10-513X 13-9-653

13-10-614 Page iv
TABLE OF CONTENTS
Maintain Compressor Reliability And Performance With Genuine
Gardner Denver Compressor Parts And Support Services .................................................................i
Instructions For Ordering Repair Parts ..................................................................................................i
Foreword............................................................................................................................................ii
Section 1, General Information.............................................................................................................1
Section 2, Installation..........................................................................................................................9
Section 3, Starting & Operating Procedures........................................................................................20
Section 4, Controls & Instrumentation.................................................................................................23
Section 5, Lubrication - Oil Cooler, Oil Filter & Separator.....................................................................37
Section 6, Air Filter............................................................................................................................57
Section 7, Coupling...........................................................................................................................59
Section 8, Maintenance Schedule......................................................................................................62
Section 9, Troubleshooting................................................................................................................64

13-10-614 Page v
INDEX
Addition Of Oil Between Changes ..................44
Air Filter Element Life....................................58
Air Filter, Section 6........................................57
Air Flow In The Compressor System................1
Air-Cooled Units, Location.............................10
AutoSentry Operation....................................23
Auxiliary Air Receiver....................................13
Cold Ambient Operation ................................44
Cold Weather Installation...............................12
Cold Weather Operation................................12
Compression Principle.....................................1
Compressor Capacity Control........................28
Compressor Oil Cooler - Water-Cooled Heat
Exchanger.................................................51
Compressor Oil System Check......................55
Control Devices ............................................23
Control Piping...............................................13
Controls & Instrumentation, Section 4.............23
Cooling, Sealing And Lubrication.....................2
Coupling.......................................................59
Coupling, Section 7.......................................59
Daily Check..................................................22
Decals............................................................8
Decals............................................................7
Discharge Service Line..................................14
Electrical Wiring............................................18
Element Life, Air Filter...................................58
Enclosure.....................................................11
Filter
Compressor Oil .........................................49
Filter Element ...............................................57
Filter, Heavy Duty Air (Standard)....................57
Foundation...................................................11
General Information, Section 1.........................1
Grounding ....................................................18
High Temperature Operation.........................38
Inlet Line ......................................................14
Inlet Tube.....................................................58
Installation For Cold Cold Weather Operation .12
Installation, Section 2......................................9
Lifting Unit......................................................9
Location .........................................................9
Air-Cooled Units........................................10
Water-Cooled Units ...................................10
Lubricant
Recommended..........................................37
Lubricant Change Procedure.........................45
Lubrication
Motor........................................................19
Lubrication, Cooling And Sealing.....................2
Lubrication, Section 5....................................37
Maintenance Schedule, Section 8..................62
Moisture In The Oil System ...........................38
Moisture Separator/Trap................................13
Motor Lubrication..........................................19
Oil Change Interval .......................................46
Oil Cooler
Compressor..............................................50
Oil Level Gauge............................................46
Oil Reservoir.................................................53
Oil Reservoir Drain........................................11
Oil Separator
Compressor (GD Eliminator).......................53
Inspection .................................................54
Oil Carryover.............................................53
Removal For Inspection Or Replacement ....55
Oil Specifications ..........................................37
Oil System
Compressor..............................................37
Draining And Cleaning ...............................47
Filling Oil Reservoir....................................48
Oil System Check.........................................55
Air And Oil Discharge Temperature.............55
Compressor Oil Inlet Temperature..............55
Oil Cooler Oil Pressure Differential..............55
Oil Cooler Oil Pressure Differential (Air-
Cooled Radiator)....................................55
Oil Cooler Temperature Differential.............55
Oil Cooler Temperature Differential (Air-
Cooled Radiator)....................................55
Oil Cooler Water Pressure Differential.........56
Oil Inlet Pressure.......................................55
Operation
Cold Ambient.............................................44
Piping
Aftercooler................................................43
Blowdown Valve........................................16
Control......................................................13
Heat Exchanger (Oil).................................43
Parallel .....................................................18
Series .......................................................18
Water........................................................16
Pressure Differential Gauging........................54
Prestart-Up Instructions.................................20
Remote Mounted Elevated Cooler Assembly
Procedure.................................................42
Safety Precautions..........................................6
Sealing, Lubrication And Cleaning....................2
Service Check List........................................62
Every 1000 Hours Operation ......................62
Every 125 Hours Operation........................62

13-10-614 Page vi
Every 8 Hours Operation............................62
Every 8000 Hours Operation ......................62
Every Year................................................63
Motor Lubrication.......................................62
Oil Separator.............................................62
Service Check List
Air Filter....................................................62
Starting & Operating Procedures, Section 3....20
Starting The Unit...........................................22
Unit Cold...................................................22
Unit Hot.....................................................22
Stopping The Unit.........................................22
Thermal Control (Thermostatic Mixing) Valve..50
Troubleshooting, Section 9............................64
Turn Valve......................................................2
Water Flow Control Valve For Heat Exchanger
................................................................52
Water Piping.................................................16
Water Shutoff Valve - Water-Cooled Heat
Exchanger.................................................52
Water-Cooled Units, Location ........................10

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LIST OF ILLUSTRATIONS
Figure 1-1 – Compression Cycle..........................................................................................................1
Figure 1-2 – Starter Box ......................................................................................................................3
Figure 1-3 – Package – Controller & Starters........................................................................................3
Figure 1-4 – Package – Drive Motor & Air Filter.....................................................................................4
Figure 1-5 – Package – Oil Filter, Oil Level Gauge, Mixing Valve ...........................................................5
Figure 1-6 – Package – Air/Oil Flow Diagram........................................................................................5
Figure 2-1 – Typical Compressor Room.............................................................................................10
Figure 2-2 – Air Flow Chart................................................................................................................10
Figure 2-3 – Cold Weather Installation................................................................................................12
Figure 2-4 – Inlet Line Lengths...........................................................................................................13
Figure 2-5 – Heat Exchanger (Oil Cooler) Approximate Water Flow......................................................15
Figure 2-6 – Aftercooler Approximate Water Flow...............................................................................15
Figure 2-7 – Series Piping .................................................................................................................17
Figure 2-8 – Parallel Piping................................................................................................................17
Figure 4-1 – Schematic Tubing Diagram.............................................................................................24
Figure 4-2 – Minimum Discharge Pressure/Check Valve......................................................................25
Figure 4-3 – Inlet Valve .....................................................................................................................26
Figure 4-4 – Shuttle Valve .................................................................................................................26
Figure 4-5 – Blowdown Valve.............................................................................................................27
Figure 4-6 – Turn Valve Actuator (Sectioned)......................................................................................28
Figure 4-7 – Control Schematic – Compressor At Full Load.................................................................30
Figure 4-8 – Control Schematic – Compressor Fully Unloaded – Low Demand Mode Switch Off............31
Figure 4-9 – Control Schematic – Compressor Fully Unloaded – Low Demand Mode Switch On............32
Figure 4-10 – Wiring Diagram – (Wye Delta, ES+ Controller, Air-Cooled)..............................................33
Figure 4-11 – Wiring Diagram – Wye Delta ES+ Controller – Water Cooled..........................................35
Figure 5-1 – Dew Point Chart °F........................................................................................................39
Figure 5-2 – Dew Point Chart °C........................................................................................................39
Figure 5-3 – Flow Diagram ................................................................................................................40
Figure 5-4 – Oil Flow Diagram – Remote Overhead Mounted...............................................................41
Figure 5-5 – Cooler Drain Detail.........................................................................................................42
Figure 5-6 – Oil Level Gauge.............................................................................................................46
Figure 5-7 – Oil Change Interval ........................................................................................................46
Figure 5-8 – Approximate Oil System Capacities.................................................................................48
Figure 5-9 – Thermostatic Mixing Valve Element.................................................................................50
Figure 5-10 – Water Control Valve .....................................................................................................52
Figure 5-11 – Oil Separator...............................................................................................................53
Figure 6-1 – Heavy Duty Air Filter (Standard)......................................................................................57
Figure 7-1 – Installation Of Coupling Cushions....................................................................................59

13-10-614 Page 1
SECTION 1
GENERAL INFORMATION
Figure 1-1– COMPRESSION CYCLE
COMPRESSOR - The Gardner Denver Rotary Screw compressor is a single stage, positive displacement
rotary machine using meshing helical rotors to effect compression. Both rotors are supported between
high capacity roller bearings located outside the compression chamber. Single width cylindrical roller
bearings are used at the inlet end of the rotors to carry part of the radial loads. Tapered roller bearings at
the discharge end locate each rotor axially and carry all thrust loads and the remainder of the radial loads.
COMPRESSION PRINCIPLE(Figure 1-1) - Compression is accomplished by the main and secondary
rotors synchronously meshing in a one-piece cylinder. The main rotor has four (4) helical lobes 90°apart.
The secondary rotor has five (5) matching helical grooves 72°apart to allow meshing with main rotor
lobes.
The air inlet port is located on top of the compressor cylinder near the drive shaft end. The discharge port
is near the bottom at the opposite end of the compressor cylinder. Figure 1-1, is an inverted view to show
inlet and discharge ports. The compression cycle begins as rotors unmesh at the inlet port and air is
drawn into the cavity between the main rotor lobes and secondary rotor grooves (A). When the rotors
pass the inlet port cutoff, air is trapped in the interlobe cavity and flows axially with the meshing rotors (B).
As meshing continues, more of the main rotor lobe enters the secondary rotor grove, normal volume is
reduced and pressure increases.
Oil is injected into the cylinder to remove the heat of compression and seal internal clearances. Volume
reduction and pressure increase continues until the air/oil mixture trapped in the interlobe cavity by the
rotors passes the discharge port and is released to the oil reservoir (C). Each rotor cavity follows the
same “fill-compress-discharge” cycle in rapid succession to produce a discharge air flow that is
continuous, smooth and shock free.
AIR FLOW IN THE COMPRESSOR SYSTEM (Figure 5-3, page 40) - Air enters the air filter and passes
through the inlet unloader valve to the compressor. After compression, the air/oil mixture passes into the
oil reservoir where most of the entrained oil is removed by velocity change and impingement and drops
back into the reservoir. The air and remaining oil passes into the separator and separator housing where
the oil is separated and passes through tubing connecting the separator housing and compressor. The
air passes through the minimum pressure valve, discharge check valve and cooler, then to the plant air
lines.

13-10-614 Page 2
LUBRICATION, COOLING AND SEALING - Oil is forced by air pressure from the oil reservoir through
the oil cooler, thermostatic mixing valve, and oil filter and discharges into the compressor main oil gallery.
A portion of the oil is directed through internal passages to the bearings, gears and shaft oil seal. The
balance of the oil is injected directly into the compression chamber to remove heat of compression, seal
internal clearances and lubricate the rotors.
TURN VALVE- The turn valve is a rotary helical valve located on the discharge side of the cylinder
toward the inlet end. The valve opens and closes ports in the cylinder which communicates with the inlet
passage. This varies the compressor rotor volume to match the demand for air, thus reducing the part-
load power requirement.

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Figure 1-2– STARTER BOX
Figure 1-3– PACKAGE – CONTROLLER & STARTERS
201EAU797
(Ref. Drawing)

13-10-614 Page 4
Figure 1-4– PACKAGE – DRIVE MOTOR & AIR FILTER
201EAU797
(Ref. Drawing)

13-10-614 Page 5
Figure 1-5– PACKAGE – OIL FILTER, OIL LEVEL GAUGE, MIXING VALVE
MINIMUM PRESSURE VALVE & CHECK VALVE
Figure 1-6– PACKAGE – AIR/OIL FLOW DIAGRAM
201EAU797
(Ref. Drawing)

13-10-614 Page 6
SAFETY PRECAUTIONS
Safety is everybody’s business and is based on your use of good common sense. All situations or
circumstances cannot always be predicted and covered by established rules. Therefore, use your past
experience, watch out for safety hazards and be cautious. Some general safety precautions are given
below:
DANGER
Failure to observe these notices could result in injury to or death of personnel.
•Keep fingers and clothing away from revolving fan, drive coupling, etc.
•Do not use the air discharge from this unit for breathing – not suitable for human consumption.
•Do not loosen or remove the oil filler plug, drain plugs, covers the thermostatic mixing valve or
break any connections, etc., in the compressor air or oil system until the unit is shut down and
the air pressure has been relieved.
•Electrical shock can and may be fatal.
•Perform all wiring in accordance with the National Electrical Code (NFPA-70) and any applicable
local electrical codes. Wiring and electrical service must be performed only by qualified
electricians.
•Open main disconnect switch, tag and lockout before working on the control.
•Disconnect the compressor unit from its power source, tag and lockout before working on the
unit – this machine is automatically controlled and may start at any time.
WARNING
Failure to observe these notices could result in damage to equipment.
•Stop the unit if any repairs or adjustments on or around the compressor are required.
•Disconnect the compressor unit from its power source, tag and lockout before working on the
unit – thismachine is automatically controlled and may start at any time.
•An Excess Flow Valve should be on all compressed air supply hoses exceeding 1/2 inch
inside diameter (OSHA Regulation, Section 1926.302).
•Do not exceedthe rated maximum pressure values shown on the nameplate.
•Do not operate unit if safety devices are not operating properly. Check periodically. Never
bypass safety devices.

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DECALS
206EAQ077 212EAQ077
218EAQ077
211EAQ077 207EAQ077

13-10-614 Page 8
DECALS
216EAQ077
217EAQ077
222EAQ077
221EAQ077 208EAQ077

13-10-614 Page 9
SECTION 2
INSTALLATION
GENERAL - On receipt of the unit, check for any damage that may have been incurred during transit.
Report any damage or missing parts as soon as possible.
CAUTION
Do not electric weld on the compressor or base; bearings can be damaged by
passage of current.
LIFTING UNIT - Proper lifting and/or transporting methods must be used to prevent damage. Lifting slots
are provided in the base for tow motor use. The unit may also be moved into location by rolling on bars.
CAUTION
Lift compressor unit by base only. Do not use other places such as motor,
compressor or discharge manifold piping as lifting points.
DANGER
The eyebolts or lugs provided on the motor are for lifting the motor only and
should not be used to lift any additional weight. All eyebolts must be securely
tightened. When lifting the motor, the lifting angle must not exceed 15 degrees.
Failure to observe this warning may result in damage to equipment or personal
injury.
DANGER
Compressor, air/oil reservoir, separator chamber and all piping and tubing may
be at high temperature during and after operation.
LOCATION - The compressor should be installed, whenever possible, in a clean, well-lighted, well-
ventilated area with ample space all around for maintenance. Select a location that provides a cool,
clean, dry source of air. In some cases it may be necessary to install the air filter at some distance from
the compressor to obtain proper air supply.
Both the air-cooled and water-cooled units require cooling air as well as air to the compressor inlet.
Proper ventilation MUST be provided; hot air must be exhausted from the compressor operating area.
Ducting air in and/or out will be required when using the quiet enclosure. A typical inlet-outlet air flow
arrangement is shown in Figure 2-1, page 10.

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Figure 2-1– TYPICAL COMPRESSOR ROOM
Minimum Air Flow * for Compression
and Cooling
DOMESTIC (CFM)
HP Air-Cooled
Package Air-Cooled Module Water-Cooled Package
200 28,500 20,500 8,000
250 35,900 26,000 9,900
300 37,900 26,000 11,900
INTERNATIONAL (M3/MIN)
KW Air-Cooled
Package Air-Cooled Module Water-Cooled Package
150 806 580 226
186 1,016 736 280
224 1,072 736 337
* 80°F (27°C) Inlet Air
Figure 2-2– AIR FLOW CHART
Air-Cooled Units- A combination oil/aftercooler is supplied as standard equipment on all air-cooled
units. The air-cooled unit with the standard enclosure requires sufficient flow, Figure 2-2, for the
compressor oil/aftercooling system and for electric motor cooling. Air is drawn into the unit at the motor
side of the enclosure and is exhausted at the oil cooler side. Do not block the air flow to and from the
unit. Allow three and one-half (3-1/2) feet (1.1 m) to the nearest obstruction on the starter end and control
box end of the unit. Allow three (3) feet (.9 m) to the nearest obstruction above and on other sides of unit.
For continuous efficiency, oil cooler cores must be periodically cleaned with either vacuum or compressed
air. If wet cleaning is required, shield motor and spray on a mild soap solution and flush with clean water.
Water-Cooled Units- The water-cooled unit with the standard enclosure requires sufficient air flow,
Figure 2-2, page 10, for electric motor cooling. Air is drawn into the unit at the top of the enclosure and is
exhausted at the motor side. Do not block air flow to and from unit. Allow three and one-half (3-1/2) feet

13-10-614 Page 11
(1.1 m) to the nearest obstruction on the starter end and control box side of the unit. Allow three (3) feet
(.9 m) to the nearest obstruction above and on other sides of the unit.
WARNING
For aluminum oil coolers, do not use any cleaning solution that is not
compatible with aluminum. Use of improper solution may result in damage to
the cooler.
FOUNDATION - The Gardner Denver Rotary Screw compressor requires no special foundation, but
should be mounted on a smooth, solid surface. Whenever possible install the unit near level. Temporary
installation may be made at a maximum 10°angle lengthwise or 10°sidewise.
Mounting bolts are not normally required. However, installation conditions such as piping rigidity, angle of
tilt, or danger of shifting from outside vibration or moving vehicles may require the use of mounting bolts
and shims to provide uniform support for the base.
OIL RESERVOIR DRAIN - The oil drain is piped from the bottom of the reservoir to the side of the frame.
This drain is approximately 4.50 inches (115 mm) above the floor level. If this is not sufficient to
conveniently drain the oil some other methods of providing drain are:
1. Elevate the compressor unit on a suitable structure to obtain the desired drain height.
CAUTION
If the compressor unit base is raised above floor level, the space between the
floor and the base bottom must be closed with solid material all around to
prevent recirculation of hot air from the oil cooler end and over temperature
operation.
2. Construct an oil sump or trough below the floor level and pump or bail the drained oil.
3. Pump oil from the reservoir filler opening or drain to a container.
ENCLOSURE - The compressor, electric motor, oil cooler and aftercooler are mounted inside the
enclosure. Service doors are provided for maintenance access. Be sure to allow enough space around
the unit for the doors to open completely.
Any of the enclosure doors may be removed by opening the door and lifting it up slightly to disengage the
hinges.
WARNING
Ducting will be required on air-cooled quiet enclosure machines.

13-10-614 Page 12
DANGER
Do not operate the compressor with the fan and coupling guard removed.
Exposed fan and couplings may cause injury to personnel.
Figure 2-3– COLD WEATHER INSTALLATION
INSTALLATION FOR COLD WEATHER OPERATION (Figure 2-3) - It is recommended that the unit be
installed inside a shelter that will be heated to temperatures above freezing (32°F, 0°C). This will
eliminate many of the problems associated with operating units in cold climates where freezing rain,
drifting snow, freezing condensate and bitter cold temperatures are encountered.
Refer to Engineering Data Sheet 13-9-411 for the advantages of using the heat recovered from rotary
compressors. This heat recovery could easily pay for an adequate shelter for the unit.
When an outside installation must be made, the precautions required will depend on the severity of the
environment. The following are general guidelines for outside installations:
Cold Weather (Down To +10°F, -12°C)
1. Be sure all drains, traps, and control lines, including pressure transducer lines are heated to avoid
freezing of condensate. Heat tape with thermostat control is generally satisfactory for this purpose
and can be obtained at various local plumbing or hardware outlets at nominal cost.
2. If an air-cooled aftercooler is to be used, provisions to bypass the aftercooler must be made. Since
cold air contains very little moisture, successful operation can be achieved without the aftercooler.
3. Provide at least some simple shelter such as a plywood windbreak to protect against drifting snow.
4. Use only Gardner Denver AEON 9000SP lubricant.
5. Monitor the unit carefully during start-up and operation to be sure it is functioning normally.
204EAU797
(Ref. Drawing)

13-10-614 Page 13
6. Specify NEMA 4 enclosure for electrical devices.
Extreme Cold Weather Operation (Down To -10°F, -23°C)
In addition to the above, the following should be provided:
1. It will be necessary to provide shutters or to block off part of the cooler in some manner since the
cooler is greatly oversized for operation in these low temperatures. Since shutters are not provided
as a factory option, blocking off a portion of the cooler with plywood should be satisfactory.
2. Auto mode should not be used in extreme environments.
3. Some means of providing heat during shutdown should be provided. There are various methods to
accomplish this, but since openings are not provided for sump heaters, the use of radiant heaters is
recommended. The heaters should be sized to provide at least a +10°F (-12°C) environment for
coolers, motor and sump. Figure 2-3, page 12, shows how these might be located in a typical
installation and sizes required.
Remember unsheltered (outside) installations should be avoided where possible. Installation next to a
heated building where enough heat can be used to keep the compressor room above freezing will save
many complications in the operation and installation of the unit.
Refer to Engineering Data Sheet 13-9-411, available from an authorized Gardner Denver distributor, for
the advantages of using the heat recovered from rotary compressors. This heat recovery could easily
pay for an adequate shelter for the unit.
AUXILIARY AIR RECEIVER - An auxiliary air receiver is not required if the piping system is large and
provides sufficient storage capacity to prevent rapid cycling. When used, an air receiver should be of
adequate size, provided with a relief valve of proper setting, a pressure gauge and a means of draining
condensate.
MOISTURE SEPARATOR/TRAP - Since the unit is equipped with a built-in aftercooler, a combination
moisture separator and trap is furnished with the unit. A means of draining condensate will be needed.
CONTROL PIPING - Control piping is not necessary since the Electra-Saver unit is factory wired and
piped for the control system specified.
Length of Inlet Line Diameter of Pipe Size
0 to 10 Feet (0 to 3 Meters) Same as Compressor Inlet Opening
10 to 17 Feet (3 to 5 Meters) One Size Larger Than Inlet Opening
17 to 38 Feet (5 to 11.5 Meters) Two Sizes Larger Than Inlet Opening
Figure 2-4– INLET LINE LENGTHS