Gardner Denver EFD-25 HP Service manual

GARDNER DENVERR
ELECTRA--SCREW
STATIONARY BASE--MOUNTED
COMPRESSORS
MODELS
EFD -- 25, 30, 40 & 50 HP
PARTS LIST,
OPERATING AND
SERVICE MANUAL
13--8--625
1st Edition
March 24, 2000

13--8--625 Page i
TOTAL PRODUCT SUPPORT -- GARDNER DENVER’S
CONTINUING COMMITMENT
TO YOUR AIR COMPRESSOR PERFORMANCE
Commitment to totalproduct support continueslong after the purchase of yourquality GardnerDenverR
rotary screw compressor.
Gardner Denver original parts incorporate years of experience and improvements in design, materials
and quality assurance. Maintaining your compressor investment with Gardner Denver parts will insure
protection for the air compressor unit and long, dependable service life.
YourauthorizedGardnerDenvercompressordistributormaintainsacompletestockofallcommonmain-
tenanceparts,factoryapprovedAeontlubricants,andGardnerDenverfactorywarrantedexchangeair-
ends. In addition,authorized distributortechniciansarefactory trained, and can provide completediag-
nostic, compressor maintenance and repair services.
This manual is designed to assist you in maintaining high performance and receiving many years of de-
pendable service you expect from your Gardner Denver compressor.
REMANUFACTURED AIRENDS
Whenever an airend requires replacement or repair,
Gardner Denver offers an industry unique, factory
remanufactured airend exchange program. From its
modern Remanufacturing Center in Indianapolis, IN,
Gardner Denver is committed to supplying you with the
highest quality, factory remanufactured airends that are
guaranteed to save you time, aggravation and money.
Immediately Available
Repair downtime costs you money, which is why there
are over 200 remanufactured units in inventory at all
times, ready for immediate delivery.
Skilled Craftsmen
Our Remanufacturing assembly technicians average
over 20 years experience with air compression products.
Precision Remanufacturing
All potentially usable parts are thoroughly cleaned, in-
spected and analyzed. Only those parts that can be
brought back to original factory specifications are re-
manufactured. Every remanufactured airend receives
anewoverhaul kit: bearings, gears, seals, sleeves and
gaskets.
Extensive Testing
Gardner Denver performs testing that repair houses
just don’t do. Magnaflux and ultrasonic inspection spot
cracked or stressed castings, monochromatic light
analysis exposes oil leaks, and coordinate measure-
ment machine inspects to +/-- .0001”, insuring that all
remanufactured airends meet factory performance
specifications.
Warranty
GardnerDenverbacksupeveryremanufacturedairend
with a new warranty . . . 18 months from purchase, 12
months from service.
GardnerDenverremanufacturedairendsdeliverquality
without question ...yearinandyearout.
Call Gardner Denver for information on the airend ex-
change program and the name of your authorized dis-
tributor.
Phone Number: 800--245--4946 or
FAX: [phone]

13--8--625 Page ii
FOREWORD
Rotary screw compressors are the result of advanced engineering and skilled manufacturing. To be assured of re-
ceiving 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 mini-
mum downtime.
Dangerisusedtoindicatethepresenceofahazardwhichwillcauseseverepersonal
injury, death, or substantial property damage if the warning is ignored.
Warning is used to indicate the presence of a hazard which can cause severe per-
sonal injury, death, or substantial property damage if the warning is ignored.
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 is used to notify people of installation, operation or maintenance informa-
tion which is important but not hazard--related.
This book covers the following models:
HP PSI Air Cooled
25, 30, 40 & 50 100, 125, 150, 175 EFD

13--8--625 Page iii
TABLE OF CONTENTS
PAGE
Total Product Support -- Gardner Denver’s Continuing Commitment To Your Air Compressor Performance i....
Remanufactured Airends i...........................................................................
Foreword ii........................................................................................
Maintain Compressor Reliability and Performance With Genuine Gardner Denver Compressor
Parts and Support Services iv..................................................................
Instructions for Ordering Repair Parts iv...............................................................
Index vthruvii.....................................................................................
List of Illustrations viii...............................................................................
Section 1, General Information 1.....................................................................
Section 2, Installation 6.............................................................................
Section 3, Starting & Operating Procedures 11.........................................................
Section 4, Controls & Instrumentation 13..............................................................
Section 5, Lubrication, Oil Cooler, Oil Filter & Separator 27..............................................
Section 6, Air Filter 35..............................................................................
Section7,BeltDrive 36.............................................................................
Section 8, Maintenance Schedule 39.................................................................
Section 9, Trouble Shooting 40.......................................................................
Section 10, Parts List 41............................................................................
Bare Compressor 43..........................................................................
Airend Group 44, 45.........................................................................
Inlet Valve Repair Parts 46, 47.................................................................
Minimum Pressure/Check Valve 48, 49.........................................................
Airend And Inlet Filter Assembly 50, 51.........................................................
Drive Groups 52 Thru 61......................................................................
Cooling Group 62, 63.........................................................................
Control System Assembly And Mounting 64, 65..................................................
Water Separator Assembly 66..................................................................
Control Box 67, 68, 69........................................................................
Enclosure Group 70, 71......................................................................
Quiet Enclosure 72...........................................................................
Main Motor 73...............................................................................
Repair Kits 74, 75............................................................................
Warranty Last Page................................................................................

13--8--625 Page iv
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 are
incorporated in our genuine replacement parts.
Your authorized Gardner Denver Compressor distribu-
tor offers all the backup you’ll need. A worldwide net-
work of authorized distributors provides the finest
product support in the air compressor industry. Your
local authorized distributor maintains a large inventory
of genuine parts.
Your authorized distributor can support your Gardner
Denver air compressor with these services:
1. Trained parts specialists to assist you in select-
ing the correct replacement parts.
2. Factory warranted new and remanufactured
rotary screw air ends. Most popular model
remanufactured air ends are maintained in stock
at Gardner Denver for purchaseon an exchange
basis with liberal core credit available for the re-
placement 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 com-
pressor.
Authorized distributor service technicians are factory--
trained and skilled in compressor maintenance and re-
pair. They are ready to respond and assist you by pro-
viding 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 Gardner Denver
Master Distribution Center 1800 Gardner Expressway
5585 East Shelby Drive Quincy, IL 62301
Memphis, TN 38141 Phone: [phone]
Phone: [phone] Fax: [phone]
(800) 245--4946
Fax: [phone]
INSTRUCTIONS FOR ORDERING REPAIR PARTS
When ordering parts, specify Compressor MODEL,
Method of Cooling, HORSEPOWER and SERIAL
NUMBER (see nameplate on unit).
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 RE-
QUIRED.
DO NOT ORDER BY SETS OR GROUPS.

13--8--616 Page v
INDEX
Addition of Oil Between Changes 28..............
Air Cooled Unit 7...............................
AIR FILTER, SECTION 6 35.....................
Air Filter, Standard Duty 35......................
Air Filter Element 35............................
Air Filter Element Life 35........................
Air Flow in Compressor System 1................
Air Pilot Electronic Control Operation 14...........
Air Pilot Electronic Controller 13..................
Basic Display 16............................
Multi--Compressor Control 18................
Multipilot Menu 18..........................
Remote Control Operation 18................
Service Menu 18...........................
User Menu 17..............................
Air Receiver, Auxiliary 8.........................
Air/Oil Separators, Compressor 33...............
Alarms 22.....................................
Automatic Start/Stop 14.........................
Auxiliary Air Receiver 8.........................
BELT DRIVE, SECTION 7 36....................
Belt Tension, Checking 37.......................
Blowdown Valve 19, 20..........................
Check, Daily 12................................
Checking Belt Tension 37.......................
Cold Ambient Operation 28......................
Cold Weather Operation 8.......................
Cold Weather Operation, Installation for 7.........
Compression Principle 1........................
Compressor 1.................................
Compressor Air/Oil Separators 33................
Compressor Oil Cooler 32.......................
Compressor Oil Filter 31........................
Compressor Oil System 27......................
Compressor Oil System Check 34................
Compressor Running Fully Loaded 14............
Compressor Running Unloaded 14...............
Compressor System, Air Flow 1..................
Control Devices 19.............................
Blowdown Valve 19, 20......................
Changing Minimum Pressure/Check
Valve Seals 20..........................
Inlet Valve 20..............................
Inlet Valve Solenoid 20......................
Minimum Discharge Pressure/Check Valve 19..
Oil Level Gauge 19.........................
Pressure Transducer 22.....................
Purge Valve 20.............................
Relief Valve 19.............................
Control Piping 9................................
Control System Operation 13....................
CONTROLS & INSTRUMENTS, SECTION 4 13...
Controls & Instruments, General Description 13....
Cooler, Compressor Oil 32......................
Cooling, Sealing and Lubrication 1................
Daily Check 12................................
Decals 4, 5....................................
Discharge Service Line 9........................
Drain, Oil Reservoir 7...........................
Draining and Cleaning Oil System 29.............
Electric Motor Grease Recommendations 10.......
Electric Motor Regreasing Interval 10.............
Electrical Wiring 9..............................
Element, Air Filter 35...........................
Element Life, Air Filter 35.......................
Emergency Stop 12............................
Enclosure 7...................................
Filling Oil Reservoir 29..........................
Filter, Compressor Oil 31........................
Foundation 7..................................
Gauge, Oil Level 19, 31.........................
GENERAL INFORMATION, SECTION 1 1........
Grease Recommendations, Electric Motor 10......
Grounding 9...................................
High Temperature Operation 28..................
Inlet Line 9....................................
Inlet Line Lengths 8............................
Inlet Valve 20..................................
Inlet Valve Solenoid 20..........................
INSTALLATION, SECTION 2 6..................
Installation, General 6..........................

13--8--616 Page vi
INDEX
Installation for Cold Weather Operation 7..........
Instrument Panel 15............................
Lifting Unit 6...................................
Line, Discharge Service 9.......................
Line, Inlet 9...................................
Location 6.....................................
Lubricant, Recommended 27....................
Lubricant Upgrade Procedure 30.................
Lubrication, Motor 9............................
Lubrication, Cooling and Sealing 1................
LUBRICATION, OIL COOLER, OIL FILTER &
SEPARATOR, SECTION 5 27................
MAINTENANCE SCHEDULE, SECTION 8 39.....
Minimum Discharge Pressure/Check Valve 19.....
Minimum Pressure/Check Valve, Changing Seals 20
Moisture in the Oil System 31....................
Moisture Separator/Trap, Optional 9..............
Motor Grease Recommendations 10..............
Motor Lubrication 9.............................
Motor Regreasing Interval 10....................
Multi--Compressor Control 18....................
Oil Carry--Over 41..............................
Oil Change Interval 28..........................
Oil Cooler, Compressor 32......................
Oil Filter, Compressor 31........................
Oil Level, Procedure for Checking 28.............
Oil Level Gauge 19, 31..........................
Oil Reservoir 33................................
Filling 29..................................
Oil Reservoir Drain 7...........................
Oil Separator
Inspection 33..............................
Removal for Inspection or Replacement 33.....
Oil Specifications 27............................
Oil System
Compressor 27.............................
Draining and Cleaning 29....................
Oil System Check 34...........................
Air and Oil Discharge Temperature 34.........
Compressor Oil Inlet Temperature 34..........
Oil Cooler Oil Pressure Differential 34.........
Oil Cooler Temperature Differential 34.........
Oil Inlet Pressure 34........................
Operation, High Temperature 28.................
PARTS LIST
Airend and Inlet Filter Assembly 50, 51........
Airend Group 44, 45.........................
Bare Compressor 43........................
Control Box 67, 68, 69......................
Cooling Group 62, 63........................
Drive Groups 52 Thru 61.....................
Common Parts 53.......................
Enclosure Group 70, 71......................
Control System Assembly and
Mounting 64, 65.........................
Inlet Valve Repair Parts 46, 47................
Main Motors 73............................
Minimum Pressure/Check Valve 48, 49........
Quiet Enclosure 72.........................
Repair Kits 74, 75...........................
Water Separator Assembly 66................
PARTS LIST, SECTION 10 43...................
Piping, Control 9...............................
Pressure Differential Gauging 33.................
Pressure Transducer 22.........................
Prestart--Up Instructions 11......................
Air Filter 11................................
Compressor Oil 11..........................
Electrical 11...............................
Enclosure 12...............................
Grounding 11..............................
Operating Mode 12.........................
Piping 11..................................
Rotation 11................................
System Pressure 12........................
Procedure for Checking Oil Level 28..............
Programming and Setup Instructions for the
Airpilot Electronic Controller 15...............
Purge Valve 20................................
Recommended Lubricant 27.....................
Regreasing Interval, Electric Motor 10............
Relief Valve 19.................................

13--8--616 Page vii
INDEX
Remanufactured Air Ends i......................
Remote Control Operation 18....................
Repair Parts, Ordering Instructions iv.............
Reservoir, Oil 33...............................
Safety Precautions 3–4.........................
Sealing, Lubrication and Cleaning 1..............
Separator/Trap, Moisture, Optional 9.............
Separators, Compressor Air/Oil 33...............
Service Check List 39...........................
Air Filter 39................................
Every 1000 Hours Operation 39..............
Every 125 Hours Operation 39...............
Every 2000 Hours Operation 39..............
Every 8 Hours Operation 39..................
Every Year 39..............................
Motor Lubrication 39........................
Solenoid, Inlet Valve 20.........................
Specifications, Oil 27...........................
Starter 14.....................................
STARTING & OPERATING PROCEDURES,
SECTION 3 11.............................
Starting the Unit 12.............................
Stop, Emergency 12............................
Stopping the Unit 12............................
Thermal Control (Thermostatic Mixing) Valve 32....
Transducer, Pressure 22........................
TROUBLE SHOOTING, SECTION 9 40...........
Upgrade Procedure, Lubricant 30................
Valve
Blowdown 19, 20...........................
Inlet 20....................................
Minimum Discharge Pressure/Check 19.......
Purge 20..................................
Relief 19..................................
Thermal Control (Thermostatic Mixing) 32.....
Warranty Last Page............................
Wiring, Electrical 9.............................

13--8--616 Page viii
LIST OF ILLUSTRATIONS
Figure 1--1 Compressor Cycle 1...............................................................
Figure 1--2 Compressor Package Components 2.................................................
Figure 1--3 Description of Compressor Package Components 2....................................
Figure 2--1 Preferred Lifting Method 6..........................................................
Figure 2--2 Alternate Lifting Method 6...........................................................
Figure 2--3 Typical Compressor Room 7........................................................
Figure 2--4 Air Flow Chart 7...................................................................
Figure 2--5 Cold Weather Installation 8.........................................................
Figure 4--1 Control Schematic 13..............................................................
Figure 4--2 Starter / Control Box and Instrument Panel 15.........................................
Figure 4--3 Air Pilot Electronic Controller 16.....................................................
Figure 4--4 Compressor Running Fully Loaded 21................................................
Figure 4--5 Wiring Diagram 23.................................................................
Figure 4--6 Wiring Diagram 24.................................................................
Figure 4--7 Wiring Diagram 25.................................................................
Figure 4--8 Wiring Diagram 26.................................................................
Figure 5--1 Flow Diagram 27..................................................................
Figure 5--2 Approximate Oil System Capacities 28...............................................
Figure 5--3 Oil Change Interval 29..............................................................
Figure 5--4 Oil Level Gauge, Oil Fill and Oil Drain 31..............................................
Figure 5--5 Oil Filter 32.......................................................................
Figure 6--1 Air Filter 35.......................................................................
Figure 7--1 Drive Belt Tensioner 36.............................................................
Figure 7--2 Removing Drive Sheave 37.........................................................
Figure 7--3 Installing Bushing in Drive Sheave 38................................................
Figure 7--4 Installing Drive Sheave on Compressor or Motor 37....................................
Figure 7--5 Belt Tension -- 5 V Section V--Belts 38................................................

13--8--616 Page 1
SECTION 1
GENERAL INFORMATION
FIGURE 1--1 -- COMPRESSOR CYCLE
COMPRESSOR -- The 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.
Ball and roller bearings at the discharge end locate
each rotor axially and carry all thrust loads and the re-
mainder of the radial loads.
COMPRESSION PRINCIPLE (FIGURE1--1)--Com-
pression is accomplished by the main and secondary
rotors synchronously meshing in a one--piece cylinder.
The mainrotor has four (4) helical lobes90_apart.The
secondary rotor has five (5) matching helical grooves
72_apart to allow meshing with main rotor lobes.
Theairinletportislocatedontopofthecompressorcyl-
inder 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 beginsas
the rotors unmesh at the inlet port and air is drawn into
the cavity between the main rotor lobes and the sec-
ondary rotor grooves (A). When the rotors pass the in-
let 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 sec-
ondary 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 re-
ductionandpressureincrease continuesuntiltheair/oil
mixture trapped in the interlobe cavity by the rotors
passes thedischargeportandis releasedtotheoilres-
ervoir (C). Each rotor cavity follows the same “fill--com-
press--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 4--1, page 13) -- Air enters the air filter and
passes through the inlet unloader valve and on into the
compression chamber where oil is injected into the air.
Aftercompression,theair/oilmixturepassesintotheoil
reservoir where most of theentrained oil is removed by
velocity change and impingement and drops back into
the reservoir. The air and remaining oil then passes
through the air/oil separator. The air then passes
through the minimum pressure/check valve, the after-
cooler and the moisture separator and into the plant air
lines.
LUBRICATION, COOLING AND SEALING -- Oil is
forcedby airpressure from theoil reservoir through the
oil cooler, thermostatic mixing valve, and oil filter and
discharge into the compressor main oil gallery. A por-
tion of the oil is directed through internal passages to
the bearings and shaft oil seal. The balance of the oil
is injected directly into the compression chamber to re-
move heat of compression, seal internal clearances
and lubricate the rotors.