Bunn LPG Instruction and safety manual

BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: [phone] F X: [phone]
www.bunnomatic.com
OPERATING & SERVICE MANUAL
OFF/STOP
START
1.Placefilterinto funnel andslidefunnel into rails.
2.Momentarily pushtheswitchto "START"position.
3.Grinderwill automatically stopwhenfinished.
PERSONAL INJURY
HAZARD.
KEEP FINGERS AND
FOREIGN OBJECTS
OUT OF HOPPER
OR CHUTE OPENING.
CAUTION
LPG
LPG-2E
27091.0000 8/01 ©1996 Bunn-O-Matic Corporation
BUNN
®

2
CONTENTS
User Notices .............................................................3
E ectrica Requirements ............................................3
Operating Contro s....................................................3
C eaning....................................................................4
Coffee Grinding.........................................................4
Initia Set-Up.............................................................5
Adjustments .............................................................5
Troub eshooting ........................................................6
Service..................................................................... 8
Wiring Schematics..................................................18
INTRODUCTION
The LPG wi store up to six pounds and the LPG-2E wi store up to three pounds of who e bean coffee in each
of two hoppers and grind it to a preset grind and amount into an awaiting funne and fi ter from most commercia
drip coffee brewers. The equipment is on y for indoor use on a sturdy counter or she f. Adequate space must be
avai ab e above the grinder to raise the id when adding beans. Use on y with who e bean coffee.
The grind is preset at the factory to drip specifications as set forth by the United States Department of
Commerce and adopted by the Coffee Brewing Center of the Pan American Coffee Bureau. Adjustments may be
made to a ter both the amount and grind from the factory setting.
W RR NTY
Bunn-O-Matic Corp. (“Bunn”) warrants the equipment manufactured by it to be commercia y free from defects
in materia and workmanship existing at the time of manufacture and appearing within one year from the date of
insta ation. In addition:
1.) Bunn warrants e ectronic circuit and/or contro boards to be commercia y free from defects in materia and
workmanship for three years from the date of insta ation.
2.) Bunn warrants the compressor on refrigeration equipment to be commercia y free from defects in materia
and workmanship for two years from the date of insta ation.
3.) Bunn warrants that the grinding burrs on coffee grinding equipment wi grind coffee to meet origina factory
screen sieve ana ysis for three years from date of insta ation or for 30,000 pounds of coffee, whichever comes first.
This warranty does not app y to any equipment, component or part that was not manufactured by Bunn or that,
in Bunn’s judgement, has been affected by misuse, neg ect, a teration, improper insta ation or operation, improper
maintenance or repair, damage or casua ty.
THE FOREGOING W RR NTY IS EXCLUSIVE ND IS IN LIEU OF NY OTHER W RR NTY, WRITTEN OR
OR L, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, NY IMPLIED W RR NTY OF EITHER
MERCH NT BILITY OR FITNESS FOR P RTICUL R PURPOSE. The agents, dea ers or emp oyees of Bunn are
not authorized to make modifications to this warranty or to make additiona warranties that are binding on Bunn.
According y, statements by such individua s, whether ora or written, do not constitute warranties and shou d not
be re ied upon.
The Buyer sha give Bunn prompt notice of any c aim to be made under this warranty by te ephone at (217)
529-6601 or by writing to Post Office Box 3227, Springfie d, I inois, 62708-3227. If requested by Bunn, the Buyer
sha ship the defective equipment prepaid to an authorized Bunn service ocation. If Bunn determines, in its so e
discretion, that the equipment does not conform to the warranty, Bunn sha repair the equipment with no charge
for parts during the warranty period and no charge for abor by a Bunn Authorized Service Representative during
the warranty period. If Bunn determines that repair is not feasib e, Bunn sha , at its so e option, rep ace the
equipment or refund the purchase price for the equipment.
THE BUYER’S REMEDY G INST BUNN FOR THE BRE CH OF NY OBLIG TION RISING OUT OF THE S LE
OF THIS EQUIPMENT, WHETHER DERIVED FROM W RR NTY OR OTHERWISE, SH LL BE LIMITED, S
SPECIFIED HEREIN, TO REP IR OR, T BUNN’S SOLE OPTION, REPL CEMENT OR REFUND.
In no event sha Bunn be iab e for any other damage or oss, inc uding, but not imited to, ost profits, ost sa es,
oss of use of equipment, c aims of Buyer’s customers, cost of capita , cost of down time, cost of substitute
equipment, faci ities or services, or any other specia , incidenta or consequentia damages.
27091 082701

3
#20545.0000
USER NOTICES
Carefu y read and fo ow a notices on the grinder and in this manua . They were written for your protection.
A notices on the grinder are to be kept in good condition. Rep ace any unreadab e or damaged abe s.
#05876.0000
ELECTRIC L REQUIREMENTS
The grinder has an attached cordset and requires 2-wire, grounded service rated 120 vo ts ac, 15 amp, sing e
phase, 60 Hz for 120V mode s; 100 vo ts ac, 15 amp sing e phase, 50Hz for 100V mode s; and 230 vo ts ac, 10
amp sing e phase, 50 Hz for 230V mode s.
P1028
P1029
27091 111598
OPER TING CONTROLS
Off/On/Start Switch (Models LPG and LPG-2E)
OFF - (upper position) Switching to this position stops a operation of the
grinder.
ON - (midd e position) The switch wi return to this position after a grind
cyc e has begun and wi remain in this position after grinding has ceased.
ST RT - ( ower, momentary position) Pressing the switch to this position
and re easing initiates a grind cyc e.
Hopper Selector Switch (Model LPG-2E only)
LEFT - Switching to this position a ows beans to be ground from the eft
hopper.
RIGHT - Switching to this position a ows beans to be ground from the
right hopper.

4
CLE NING
EXTERIOR SURF CES
The use of a damp c oth rinsed in any mi d, nonabrasive, iquid detergent is recommended for c eaning a
surfaces on Bunn-O-Matic equipment. Care shou d be taken not to scratch the hopper or windows with any abrasive
materia . Regu ar c eaning wi keep your grinder ooking new for years.
GRIND CH MBER
1. W RNING - Unp ug grinder before remova of any pane or grind chamber housing parts.
2. Empty a beans from both hopper(s).
3. P ug-in the grinder, p ace funne with fi ter into funne rai s. Press the Off/On/Start switch to the “START” ower
position and re ease. Run a few grind cyc es unti a the coffee in the grind chamber is dispensed and disconnect
grinder from the power source.
4. Remove the funne with fi ter and carefu y tip the grinder over on it’s back.
5. Remove the two #10-32 screws securing burr housing cap assemb y to the burr housing and remove burr
housing cap assemb y.
6 Remove oad disc and s ide rotor with ower burr, spring and brass bushing off of the motor shaft.
7. C ean the grind chamber and a parts with a dry non meta ic brist e brush and wipe with a dry c ean c oth.
8. Reinsta brass bushing (f anged end first), spring and rotor with ower burr onto the motor shaft. Reinsta oad
disc f at side toward rotor and burr housing cap assemb y to the burr housing.
9. Refer to Initia Set-up/Adjustments section to vary grind or weight of dispensed coffee if necessary.
COFFEE GRINDING
1. On mode s LPG-2E, se ect (either eft or right hopper) with se ector switch and visua y inspect the desired
hopper for an amp e supp y of who e bean coffee.
2. P ace a paper fi ter into the brew funne . The fi ter must not be fo ded-over or ti ted to one side.
3. Insert the funne into the funne rai s and push unti it stops.
4. Momentari y press Off/On/Start switch to the "START" ower position and re ease. The grinding action wi stop
automatica y after the preset amount of ground coffee is dispensed into the funne .
5. Remove the funne from the grinder and eve the bed of grounds by gent y shaking.
6. The oaded funne is now ready for use in any commercia drip coffee brewer according to the manufacturer’s
instructions.
STEP #1 STEP #2 STEP #3 STEP #4 STEP #5
27091 111598

5
C
O
A
R
S
E
-
F
I
N
E
B
U
N
N
INITI L SET-UP/ DJUSTMENTS
The grind can be set from fine to very coarse. The grind may be adjusted for use in most commercia coffee
brewers. The fo owing procedures shou d be used to make adjustments.
NOTE - A change in the burr adjustment wi a so change the amount dispensed. Any adjustment to the burrs shou d
be fo owed by an adjustment of the timer dia s.
Burr djustment
1. Unp ug the grinder and empty a beans from the hopper(s).
2. P ug-in the grinder, p ace funne with fi ter into the funne rai s. Momentari y
press the Off/On/Start switch to the “START” ( ower) position (with desired
hopper se ected) and re ease, run a few grind cyc es unti a of the coffee in the
grind chamber is dispensed.
3. Remove the funne with fi ter and carefu y tip the grinder over on it’s back.
4. P ace the Off/On/Start switch in the “START” ( ower) position and, using the
grind adjustment key provided, s ow y turn the adjusting screw in a c ockwise
direction unti a meta ic whine is heard due to the rubbing of the grinding burrs. (It may be necessary to start
more than one grind cyc e to obtain the sound).
5. Make a mark with a pen on the deca to note the position of the arrow on the grind adjustment screw.
6. The fo owing settings approximate y correspond to the CBC recognized grinds. A are referenced from the
arrow position marked in step #5.
FINE GRIND: Rotate the adjusting screw 7 hash marks in a counterc ockwise direction.
DRIP GRIND: Rotate the adjusting screw 8 hash marks in a counterc ockwise direction.
REGUL R (CO RSE) GRIND: Rotate the adjusting screw 10 hash marks in a counterc ockwise direction.
NOTE: Exact adjustment wi vary according to bean roast or added f avoring.
P1073
P1035
27103.0000B 3/97 © 1996 BUNN-O-MATIC CORPORATION
SCHEM TIC WIRING DI GR M
LPG2E NL1
BLK
RED
WHI
120 VOLTS C
2 WIRE
SINGLE PH SE
60 HZ
GRN
3
AMP
2
3
4
5
6
1
10
7
8
9
TIMER ASSY.
GRN
WHI
BLU
YEL
WHI/BLK
BLK
RED
VIO
ORA
WHI
BLU
YEL
WHI/BLK
BLK
RED
VIO
ORA
OFF/ON/START
SWITCH
RED
RED
RED
GRN
SELECTOR
SWITCH WHI
RED
RED
WHI
BLK GRINDER
M
SLIDE GATES
RT
SOL
LT
SOL
(Hopper Side
Gate Timer
Dia Wiring)
Right - Brown
Left - Orange
RED RED
P1744
27091 111598
Timer djustment (Model LPG-2E)
1. Fi hoppers with who e bean coffee and se ect hopper to be adjusted.
2. Remove the cover frpm the timer dia s.
3. Set the timer dia to 2 seconds for each 1-1/2 ounces of ground coffee
desired.
4. Grind a few cyc es to verify the setting by weighing samp es.
5. Adjust the timer to correspond with the chart be ow.
pproximate mount (in Ounces) Timer Settings (in Seconds)
1-1/2 2
2-1/4 3
34
6. Repeat steps 2 - 4 for remaining hopper.
Timer djustment (Model LPG)
1. Unp ug the grinder and remove the 2" ho e p ug in the rear cover.
2. Set the timer dia to 5 seconds for each ounce of ground coffee desired.
3. Verify the setting by weighing a few samp es.
Use this 5 second per ounce figure as an PPROXIM TE guide only.

6
Problem
Grinder wi not start.
Remedy
(A) P ug-in the grinder.
(B) Check the vo tage at the wa
out et with a vo tmeter. It must be
120 vo ts ac for 120 vo t mode s, 100
vo ts for 100 vo t mode s, and 230
vo ts for 230 vo t mode s.
(A) Momentari y press the Off/On/
Start switch to the “START”( ower)
position.
(B) Refer to Service - Off/On/Start
switch for testing procedures. See
page 14
Press the “Reset” button, ocated on
rear of the grinder. Listen carefu y
for a “c ick”. This resets the motor
protection circuit and indicates that
an over oad may have been encoun-
tered by the motor. (An over oad can
occur when something other than
coffee is inserted into the hopper for
grinding). Refer to Service - Circuit
Breaker for testing procedure. See
page 9
Refer to Service - Timer for testing
procedures. See page 16
Probable Cause
1. No power or incorrect vo tage
2. Off/On/Start switch
3. Circuit Breaker (Not app icab e on
Mode LPG with capacitor)
4. Timer
TROUBLESHOOTING
A troub eshooting guide is provided to suggest probab e causes and remedies for the most ike y prob ems
encountered. If the prob em remains after exhausting the troub eshooting steps, contact the Bunn-O-Matic
Technica Service Department.
• Inspection, testing, and repair of e ectrica equipment shou d be performed on y by qua ified service
personne .
• A e ectronic components have ac vo tage and dc vo tage potentia on their termina s. Shorting of
termina s or the app ication of externa vo tages may resu t in board fai ure.
• Intermittent operation of e ectronic circuit boards is un ike y. Board fai ure wi norma y be permanent.
If an intermittent condition is encountered, the cause wi ike y be a switch contact or a oose connection
at a termina or crimp.
• Make certain that a e ectrica connections are tight and iso ated.
W RNING
• Exercise extreme caution when servicing e ectrica equipment.
• Turn power OFF when servicing, except when e ectrica tests are specified.
• Fo ow recommended service procedures.
• Rep ace a protective shie ds or safety notices.
27091 111598

7
TROUBLESHOOTING (cont.)
Problem Probable Cause
Remedy
Each motor is equipped with a tem-
perature and current over oad protec-
tion feature which wi immediate y
shut off the motor when an over oad
has occurred. Check the grinder for
obstructions. Refer to Service - Motor
for testing procedures. See page 11
A) P ace the switch in the “OFF" upper
position.
(B) Refer to Service - Off/On/Start
Switch for testing procedures. See
page 14
Refer to Service - Timer for testing
procedures. See page 16
Begin each grind cyc e by visua y in-
specting the hopper(s) for amp e sup-
p ies of who e bean coffee.
Foreign materia s must not b ock the
openings at the bottom of the
hopper(s).
Refer to Service - So enoids for test-
ing procedures. See page 14
Refer to Service - Timer for testing
procedures. See page 16
Refer to the Adjustments section. See
Timer adjustment page 5.
Refer to the Adjustment section. See
Burr adjustment page 5.
Rep ace the dechaffer springs. Re-
p acement dechaffer springs are pro-
vided in the iterature package
accompnting the grinder. See page 10
Refer to Service - Hopper se ector
switch for testing procedures. See
page 10
Grinder wi not start. (Continued)
Grinder wi not shut off.
Grinder starts, but wi not dispense
from either hopper.
Incorrect amount of coffee.
Incorrect coffee grind dispensed.
Excessive chaff
Grinder on y dispenses from one
hopper
5. Motor
1. Off/On/Start switch
2. Timer
1. Hopper(s)
2. B ockage of hopper(s)
3. S ide Gate So enoids (Mode
LPG-2E on y)
4. Timer
1. Timer adjustment
1. Burr adjustment
1. Dechaffer
1. Hopper se ector switch (Mode
LPG-2E on y)
27091 111598

8
Use only on a properly protected circuit
capable of the rated load.
Electrically ground the chassis.
Follow national/local electrical codes.
Do not use near combustibles.
An extension cord, when used, must be shorter
than 20 feet if 16-gage 3-conductor wire, or
shorter than 10 feet if 18-gage 3-conductor wire.
FAILURE TO COMPLY RISKS EQUIPMENT
DAMAGE, FIRE, OR SHOCK HAZARD
READ THE ENTIRE OPERATING MANUAL
INCLUDING THE LIMIT OF WARRANTY AND
LIABILITY BEFORE BUYING OR USING THIS PRODUCT
20545-0000 7/90 © 1990 Bunn-O-Matic Corporation
WARNING
CONTENTS
Capacitor ................................................................9
Circuit Breaker ........................................................9
Dechaffer ..............................................................10
Hopper Se ector Switch ........................................10
Motor.................................................................... 11
Off/On/Start Switch............................................... 14
So enoids.............................................................. 14
Timer ....................................................................16
Wiring Schematics................................................18
SERVICE
This section provides procedures for testing and
rep acing various major components used in this
grinder shou d service become necessary. Refer to
Troub eshooting for assistance in determining the
cause of any prob em.
W RNING - Inspection, testing, and repair of e ectri-
ca equipment shou d be performed on y by qua ified
service personne . The grinder shou d be unp ugged
when servicing, except when e ectrica tests are re-
quired and the test procedure specifica y states to
p ug-in the grinder.
Component ccess
W RNING - Unp ug the grinder before the remova of
any pane or the rep acement of any component.
A components are accessib e by the remova of
the hopper and the rear pane .
Remove a the coffee beans from the hopper. On
Mode LPG equipped with Hopper Burr Guard, remove
the two screws attaching the guard to the motor cover.
Remove the four #8-32 screws securing hopper to
hopper housing. Lift hopper, id and hopper divider
(LPG-2E on y) as an assemb y over the motor assem-
b y.
P1033
P1034
Remove the four #8-32 screws securing the rear
pane and knob cover for Mode LPG-2E, to the hop-
per housing. On Mode LPG-2E, et the rear pane hang
by the orange and brown wires from the timer board.
FIG. 1 HOPPER REMOVAL
FIG.2 REAR PANEL REMOVAL
27103.0000C 11/98 © 1996
BUNN-O-MATIC CORPORATION
SCHEMATIC WIRING DIAGRAM
LPG2E
NL1
BLK
RED
WHI
120 VOLTS AC
2 WIRE
SINGLE PHASE
60 HZ
GRN
3
AMP
2
3
4
5
6
1
7
8
9
10
TIMER ASSY.
(Hopper Slide
Gate Timer
Dial Wiring)
Right - Brown
Left - Orange
YEL
WHI
BLU
YEL
WHI/BLK
BLK
RED
VIO
ORA
OFF/ON/START
SWITCH
RED
RED
RED
GRN
SELECTOR
SWITCH
WHI
RED
RED
WHI
BLK
GRINDER
SLIDE GATES
RT
SOL
LT
SOL
RED RED
M
P1745
FIG. 3 CAPACITOR
Capacitor (Model LPG)
27091 111598

9
SERVICE (cont.)
Capacitor (Model LPG)(cont.)
Location:
The capacitor is ocated inside the front pane of
the hopper housing next to the Off/On/Start switch.
Test Procedure:
1. Disconnect grinder from the power source.
2. Visua y inspect the capacitor for eakage. If eak-
age is visib e, rep ace the capacitor.
3. Connect the grinder to the power source, if the
motor does not run, disconnect the capacitor
wiring harness from the main wiring harness. If
the motor now runs, rep ace the capacitor.
Remova and Rep acement:
1. Disconnect the capacitor wiring harness from the
main wiring harness.
2. Remove the #8-32 nut attaching the capacitor and
mounting bracket to the hopper housing and re-
move the bracket, shie d, capacitor and capacitor
wiring harnes as an assemb y.
3. Disconnect the wiring harness from the capacitor
and attach it to a new capacitor making sure the
b ack wire attaches to the positive (+) po e, FIG. 4.
4. Wrap the shie d around the capacitor and p ace
into the mounting bracket. S ide the ower tab of
the mounting bracket between the wrapper and
base and secure in p ace over the mounting stud
with the #8-32 nut.
5. Reconnect the wiring harness to the main wiring
harness.
Circuit Breaker
Location:
The circuit breaker is ocated on the rear of the
grinder next to the power cord strain re ief bushing.
The circuit breaker is not avai ab e on Mode LPG
equipped with capacitor.
P1036
FIG. 5 CIRCUIT BREAKER
27103.0000C 11/98 © 1996
BUNN-O-MATIC CORPORATION
SCHEMATIC WIRING DIAGRAM
LPG2E
NL1
BLK
RED
WHI
120 VOLTS AC
2 WIRE
SINGLE PHASE
60 HZ
GRN
3
AMP
2
3
4
5
6
1
7
8
9
10
TIMER ASSY.
(Hopper Slide
Gate Timer
Dial Wiring)
Right - Brown
Left - Orange
YEL
WHI
BLU
YEL
WHI/BLK
BLK
RED
VIO
ORA
OFF/ON/START
SWITCH
RED
RED
RED
GRN
SELECTOR
SWITCH
WHI
RED
RED
WHI
BLK
GRINDER
SLIDE GATES
RT
SOL
LT
SOL
RED RED
M
Test Procedure:
1. Disconnect grinder from the power source.
2. Remove the wires from the circuit breaker.
3. Check for continuity between the termina s. Con-
tinuity must be present between the termina s.
If continuity is present as described the circuit breaker
is functioning proper y.
If continuity is not present as described, press reset
button and repeat step #3, if continuity is not present
as described, rep ace the circuit breaker.
Remova and Rep acement:
1. Remove the wires from the circuit breaker.
2. Remove the face nut securing circuit breaker to the
motor support.
3. Remove circuit breaker.
4. Insta new circuit breaker in motor support and
secure with face nut.
5. Reconnect the wires.
6. Refer to FIG. 6 when reconnecting the wires.
P1037
FIG. 6 CIRCUIT BREAKER TERMINALS
P1747
FIG. 4 CAPACITOR TERMINALS
+
BLK WHI/BRN
RED from Motor-LPG-2E
BLK from Start Switch-LPG
BLK from Power Cord
27091 111598

10
P1038
Hopper Selector Switch (Model LPG-2E)
P1029
Location:
The Hopper Se ector Switch is ocated in the
ower eft front of the hopper housing.
Test Procedure:
1. Disconnect grinder from the power supp y.
2. Remove a wires from the switch termina s.
3. Check that the switch is insta ed proper y, FIG. 10.
4. P ace the se ector switch in the eft position.
5. Check for continuity across the termina s on the
rear of the switch.
If continuity is present as described proceed to #6.
If continuity is not present as described, rep ace the
switch.
6. P ace the se ector switch in the right position.
7. Check for continuity across the termina s on the
rear of the switch. Continuity shou d not be present
across termina s in the right position.
If continuity is not present as described, reconnect
the wires, the switch is operating proper y.
If continuity is present rep ace the switch.
Remova and Rep acement:
1. Remove a wires from the switch termina s.
2. Compress the c ips inside the front of the housing
and gent y push the switch through the opening.
3. Push the new switch into the opening and spread
the c ips to retain the switch in the housing.
4. Refer to Fig. 10 when reconnecting the wires.
FIG. 9 HOPPER SELECTOR SWITCH
FIG. 10 HOPPER SELECTOR SWITCH TERMINALS
(Viewed from rear)
SERVICE (cont.)
FIG. 7 DECHAFFER P1062
Location:
The dechaffer spring p ates are ocated in the burr
housing cap.
1
FIG. 8 DECHAFFER REMOVAL/REPLACEMENT
P1063
2
Remova and Rep acement: Refer to Fig. 8
1. Remove coffee beans from hopper(s).
2. Lay grinder on it’s back.
3. Remove the #4-40 truss head screw securing
dechaffer support (1) to the burr housing cap.
4. Remove dechaffer support (1).
5. Remove dechaffer spring p ate (2) from burr hos-
ing cap.
6. For mode s with extra fine dechaffer, remove
dechaffer support (3).
7 P ace new dechaffer spring p ate (2) in the s ot in
the burr housing cap.
8. P ace dechaffer support (1) over dechaffer spring
p ate (2), support (3) and secure with a #4-40
truss head screw.
WHI to OFF/ON/START Switch
BLU to Timer P1-4 (BLU)
OPTONAL EXTRA
FINE DECHAFFER
3 2 1
Dechaffer
27091 061400

11
P1022
Location:
The motor is ocated inside the hopper assemb y.
Test Procedures:
1. Disconnect grinder from the power supp y.
2. On Mode LPG-2E, disconnect the b ack wire and
the white wire to the motor from the main wiring
harness, the red wire to the circuit breaker and the
red wire to the Off/On/Start switch. On Mode LPG
disconnect the motor wiring harness from the
main wiring harness.
3. Connect the eads of an ohm meter to the red wires
from the motor.
If continuity is present the over oad is good.
If continuity is not present the over oad wi not reset,
rep ace the motor.
4. Set an ohm meter to read at east 20 ohms.
Connect the eads from the ohm meter to the b ack
wire and the white from the motor. The ohm
reading shou d be approximate y 18 ohms. Using
the bean agitator s ow y rotate the motor shaft in
approximate y 1/8 turn steps through one fu
rotation. If ohm readings are consistent motor
windings are good. If readings vary more than ±1
ohm, rep ace motor.
SERVICE (cont.)
Motor
FIG. 11 MOTOR
NOTE: C ean a grind burrs and mounting surfaces
before reassemb y.
Remova and Rep acement:
1. On Mode LPG-2E, disconnect the b ack wire and
the white wire to the motor from the main wiring
harness, the red wire to the circuit breaker and the
red wire to the Off/On/Start switch. On Mode LPG
disconnect the motor wiring harness from the
main wiring harness.
2. On Mode LPG-2E, disconnect the red wire from
the eft and right so enoid, the orange wire from
the eft so enoid and the vio et wire from the right
so enoid.
P1049
2
3
1
FIG. 12 MOTOR REMOVAL
3. Refer to Fig 12. Remove the three #10-32 x .25”
screws (1) securing the motor to the motor sup-
port bracket.
4. Remove the motor, so enoid and so enoid compo-
nents (2) from the hopper housing (3) as an
assemb y.
NOTE: Steps 5 thru 14 app y on y to Mode LPG-2E.
5. Refer to Fig.13. Remove the three #8-32 Keps
nuts.
6. Lift the retaining ring w/hopper gasket (1) over the
motor and burr housing assemb y (9). Set aside
for reassemb y.
7. Remove the fi er p ate (2) and set aside for reas-
semb y.
8. Lift s ide p ate, so enoid p unger and spring (3) off
of the dowe pin in the mounting ring (6) and s ide
so enoid p unger and spring (3) out of so enoid
coi . Set aside for reassemb y. Repeat for opposite
side.
27091 111598

12
1. Retaining Ring W/Hopper Gasket
2. Fi er P ate
3. S ide P ate, So enoid P unger and Spring
4. Spacer P ate
5. Setscrew, #10 -32
6 Mounting Ring, So enoid and So enoid Mounting
P ate
7. Setscrew, #8-32
8. Burr Housing Divider
9. Motor and Burr Housing
P1050
1
3
4
6
5
7
8
2
3
9
FIG. 13 SOLENOID AND GATES
SERVICE (cont.)
Motor (cont.)
9. S ide spacer p ate (4) off of burr housing divider
(8) and set aside for reassemb y.
10. Loosen the #10-32 setscrew (5) securing the
mounting ring and so enoid bracket (6) to the burr
housing.
11. Lift mounting ring, so enoid bracket and so enoids
(6) over the motor and burr housing assemb y (9)
and set aside for reassemb y.
12. Remove the #8-32 setscrew (7) and set aside for
reassemb y.
13. Lay motor on it’s side.
NOTE: Refer to Fig. 14 for the disassemb y and assem-
b y of the burrs and rotor.
14. Remove the two #10-32 fi ister head screw secur-
ing burr housing cap (10) to the burr housing.
15. Remove cap, burr adjusting screw, decaffing p ate
and decaffer support (10) as an assemb y. Set
aside for reassemb y.
16. Remove oad disc (11) and set aside for reassem-
b y.
17. S ide rotor (12), ower burr (13) and spring (14) as
an assemb y off the motor shaft, set aside for
reassemb y.
18. Remove burr housing divider (8) and set aside for
reassemb y.
NOTE: Inspect rotor. If rotor needs to be rep aced,
remove the two #10-32 binding head screws se-
curing ower burr (13) to the rotor and remove
burr. Insta ower burr (13) on new rotor (12)
using two #10-32 binding head screws.
19. S ide spring retaining bushing (15) off the motor
shaft and set aside for reassemb y.
20. Remove the two #10-32 binding head screws
securing the upper burr (16) to the motor and
housing assemb y (17).
21. Remove the upper burr (16) and set aside for
reassemb y.
NOTE: If burrs need to be rep aced, they must be
rep aced in matched pairs.
27091 111598

13
22. Remove the two #8-32 f at head screws securing
the motor cover (18) to the motor and housing
assemb y (17) and remove the cover. Set aside for
reassemb y.
23. Discard o d motor and housing assemb y.
24. P ace new motor on it’s side and insta motor
cover (18) using two #8-32 f at head screws.
25. Insta upper burr (16) to the new motor and
housing assemb y (17) using two #10-32 binding
head screws.
26. Insta spring retaining bushing (15) on motor
shaft.
27. Refer to Fig. 13. Insta burr housing divider (8) in
s ot in the burr housing and secure with #8-32 cup
point setscrew (7), for Mode LPG-2E on y.
28. Refer to Fig. 14. Insta rotor (12), ower burr (13)
and spring (14) as an assemb y on the motor shaft.
29. Insta oad disc (11) f at side towards rotor.
30. Insta burr housing cap (10), adjusting screw,
dechaffing spring p ate and dechaffer support as
an assemb y to the new motor and housing as-
semb y (17) using two #10-32 fi ister head screws.
31. Set motor upright with burr housing at the bottom.
NOTE: Steps 32 thru 36 app y on y to Mode LPG-2E.
32. Insta so enoids, so enoid bracket and mounting
ring (6) as an assemb y on the new motor with the
so enoids ocated to the opposite side of the burr
housing divider (8).
33. Insta spacer p ate (4) on burr housing divider (8)
making sure the ho e in the spacer p ate (4) ines
up with the ho e in the mounting ring (6).
34. Insta so enoid p unger with spring and s ide p ate
(3) as an assemb y into the so enoid coi . P ace
s ide p ate on the dowe in the mounting ring.
Repeat for the opposite side.
35. P ace fi er p ate (2) on mounting ring (6) over the
top of the s ide p ates (3) with the ho es in the fi er
p ate in ine with the ho es in the mounting ring.
36. Insta retaining ring w/hopper gasket (1) using
three #8-32 pan head screws and three #8-32 keps
nuts.
37. Refer to Fig.12. Insta motor, so enoids and so e-
noid components (2) in the hopper housing (3)
using three #10-32 truss head screws (1).
38. Reconnect wires for motor and so enoids. Refer to
wiring schematic on page 18.
FIG. 14 ROTOR/AUGER, BURRS AND MOTOR COVER
SERVICE (cont.)
Motor (cont.)
10 11 12 13 14 15 16 17 18
P1051
MODEL LPG ONLY
13
27091 111598

14
SERVICE (cont.)
OFF/ON/ST RT Switch
Location:
The Off/On/Start switch is ocated on the right
front side of the hopper housing.
Test Procedure:
1. Disconnect grinder from the power source.
2. Remove a wires from the switch termina s.
3. Check for continuity across the .187" termina s of
the switch when it is he d in the ower “START”
position. Continuity must not be present across
these termina s in the center or upper position.
If continuity is present as described, proceed to #4.
If continuity is not present as described, rep ace the
switch.
4. Check for continuity across the .25" termina s of
the switch when it is in the “ON” position. Continu-
ity must not be present in the upper “OFF” posi-
tion.
If continuity is present as described, reconnect the
wires, the switch is operating proper y.
If continuity is not present as described, rep ace the
switch.
Remova and Rep acement:
1. Remove a wires from the switch termina s.
2. Compress the c ips inside the front of the hopper
housing and gent y push the switch through the
opening.
3. Push the new switch into the opening and spread
the c ips to retain the switch in the hopper housing.
4. Reconnect a the wires to the switch termina s.
5. Refer to Fig. 16 when reconnecting the wires.
P1057
P1028
Solenoid (Model LPG-2E)
P1058
Location:
The so enoids are ocated inside the hopper hous-
ing behind the eft and right side of the motor.
Test Procedure:
1. Disconnect grinder from the power source.
2. Remove both wires from the so enoid coi termi-
na s.
3. Check the vo tage across the red wire and the vio et
wire removed from the right so enoid or the red
wire and the orange wire removed from the eft
FIG. 15 OFF/ON/START SWITCH
FIG. 16 OFF/ON/START SWITCH TERMINALS
(Viewed from rear)
FIG. 17 SOLENOIDS
RED from Motor
RED to Left and Right
So enoid - LPG-2E
BLK to Power
Cord - LPG
YEL to Timer P1-5 - LPG-2E
WHI/BRN to Timer P1-5 - LPG
WHI from Power Cord to Hopper
Se ector Switch - LPG-2E
WHI/BLU to Timer P1-4 - LPG
27091 111598

15
so enoid with a vo tmeter. Connect the grinder to
the power source and p ace the Off/On/Start switch
in the “ON” center position. The indication must be
120 vo ts AC.
4. Disconnect the grinder from the power source.
If vo tage is present as described, proceed to #5.
If vo tage is not present as described, refer to the
wiring diagram and check grinder wiring harness.
5. Check for continuity across the so enoid coi ter-
mina s.
If continuity is present as described, reconnect the
vio et wire and the red wire on the right so enoid or the
orange wire and the red wire on the eft so enoid.
If continuity is not present as described, rep ace the
so enoid.
6. Check the so enoid for coi action when the Off/On/
Start switch is momentari y pressed to the “START”
( ower) position and re eased. Connect grinder to
the power source. Watch the s ide gate open and
c ose as the coi magnet attracts and after a period
of time, re eases the p unger.
7. Disconnect the grinder from the power source.
If the s ide gate functions as described the so enoid is
operating correct y.
If the s ide gate does not function as described, rep ace
the so enoid.
Remova and Rep acement: Refer to Fig. 18
1. Loosen the two #8-32 pan head screws securing
the timer mounting bracket to motor support.
2. Move timer bracket, timer and rear cover (1) away
from the rear of the eft so enoid.
3. Remove the shou der screw (2) securing the so e-
noid to the so enoid mounting p ate (6). Set aside
for reassemb y.
4. S ide so enoid (4) and so enoid mounting bracket
(3) off of the so enoid p unger (5).
5. Remove the four #8-32 truss head screw securing
the so enoid (4) to the so enoid mounting bracket
SERVICE (cont.)
Solenoid (cont.)
1 6 2
3 4 5
P1059
(3). Set mounting bracket (3) and the four screws
aside for reassemb y.
6. Insta new so enoid (4) on mounting bracket (3)
using four #8-32 truss head screws.
7. S ide new so enoid (4) and mounting bracket (3)
on the so enoid p unger (5) far enough so the ho e
in the mounting bracket (3) is in ine with the ho e
in the so enoid mounting p ate (6).
8. Insta shou der screw (2).
9. S ide timer mounting bracket and timer (1) under
the two #8-32 pan head screws on the eft rear of
the motor support and tighten screws.
10. Repeat steps #3 through #8 for the right so enoid.
11. Refer to Fig. 19 and reconnect the wires to the
so enoid coi termina s.
P1060
FIG. 18 SOLENOID REMOVAL AND INSTALLATION
FIG. 19 SOLENOID COIL TERMINALS
27091 111598

16
SERVICE (cont.)
Timer (Model LPG-2E)
P1061
Location:
The timer is ocated inside the hopper housing just
behind the eft so enoid.
Test Procedure:
1. Disconnect grinder from the power source.
2. Insert the eads of a vo tmeter set to read at east
120 vo ts AC, a ong side the red wire (termina 8)
and the white wire (termina 2) of the harness p ug.
P ace the Off/On/Start switch in the “ON” center
position. Connect the grinder to the power source.
The indication must be 120 vo ts AC.
3. Disconnect the grinder from the power source.
If vo tage is present as described, proceed to step #4.
If vo tage is not present as described, refer to the wir-
ing diagram and check the grinder wiring harness.
4. P ace the hopper se ector switch in the eft posi-
tion.
5. Insert the eads of a vo tmeter set to read at east
120 vo ts AC, a ong side the red wire (termina 8)
and the orange wire (termina 10) of the harness
p ug. P ace the Off/On/Start switch in the “START”
ower position. Connect the grinder to the power
source. The indication must be 120 vo ts AC for
the set gate time and return to 0 vo ts.
6. Disconnect the grinder from the power source.
If vo tage is present as described, proceed to step #7.
If vo tage is not present as described, rep ace the timer.
FIG. 20 TIMER
7. P ace the hopper se ector switch in the right posi-
tion.
8. Insert the eads of a vo tmeter set to read at east
120 vo ts AC, a ong side the red wire (termina 8)
and the vio et wire (termina 9) of the harness p ug.
P ace the Off/On/Start switch in the “START” ower
position. Connect the grinder to the power source.
The indication must be 120 vo ts AC for the set
gate time and return to 0 vo ts.
9. Disconnect the grinder from the power source.
If vo tage is present as described, proceed to step#10.
If vo tage is not present as described, rep ace the timer.
10. Insert the positive (+) ead of a vo t meter set to
read at east 120 vo ts DC, a ong side the b ack
wire (termina 7) of the harness p ug and insert
the negative (-) ead a ong side the white/b ack
wire (termina 6) of the harness p ug. P ace the
Off/On/Start switch in the “START” ower position.
Connect the grinder to the power source. The in-
dication must be 120 vo ts DC for the set gate
time p us c ean out time and return to 0 vo ts.
If vo tage is present as described the timer is operat-
ing proper y.
If Vo tage is not present as described, rep ace the timer.
Remova and Rep acement:
1. Disconnect the main wiring harness p ug from the
termina b ock on the timer.
2. Remove the two timer dia knobs ocated on the
rear pane of the grinder.
3. Remove nut and interna tooth ockwasher secur-
ing dia s to the rear pane .
4. Loosen the two #8-32 pan head screws securing
the timer and timer mounting bracket to the motor
support p ate.
5. Remove timer and timer mounting bracket from
the grinder.
6. Remove the four #6-32 keps nuts securing the
timer to the mounting bracket. Leave the four
spacers on the mounting bracket studs.
7. P ace new timer over the studs on the mounting
bracket and secure with four #6-32 keps nuts.
27091 111598

17
8. S ip timer and timer mounting bracket under the
two screws on the motor support p ate and tighten
screws.
9. Locate the eft and right timer dia s in their proper
p ace on the rear pane and secure with nuts and
interna tooth ockwashers.
10. P ace timer knobs on timers.
11. Reconnect harness p ug to the termina b ock on
the timer board.
SERVICE (cont.)
Timer (Model LPG-2E)
Timer (Model LPG)
P1748
FIG. 21 TIMER
Location:
The timer is ocated inside the rear access pane .
Adjustments can be made by removing the 2" ho e
p ug.
Test Procedure:
1. Disconnect grinder from the power source.
2. Insert the eads of a vo tmeter set to read at east
120 vo ts AC, a ong side the red wire (termina 1)
and the white/b ack wire (termina 2) of the har-
ness p ug. P ace the Off/On/Start switch in the
“ON” center position. Connect the grinder to the
power source. The indication must be 120 vo ts
AC for 120 vo t mode s, 100 vo ts for 100 vo t
mode s, and 230 vo ts for 230 vo t mode s.
3. Disconnect the grinder from the power source.
If vo tage is present as described, proceed to step #4.
If vo tage is not present as described, refer to the wir-
ing diagram and check the grinder wiring harness.
4. Insert the positive (+) ead of a vo t meter set to
read at east 120 vo ts DC (157 vo ts DC on units
with capacitor), a ong side the b ack wire (termi-
na 3) of the harness p ug and insert the negative
(-) ead a ong side the white wire (termina 6) of
the harness p ug. P ace the Off/On/Start switch in
the “START” ower position. Connect the grinder
to the power source. The indication must be 120
vo ts DC for 120 vo t mode s (157 vo ts DC on
units with capacitor), 100 vo ts for 100 vo t mod-
e s, and 230 vo ts for 230 vo t mode s for the set
time and return to 0 vo ts.
5. Disconnect the grinder from the power source.
If vo tage is present as described the timer is operat-
ing proper y.
If Vo tage is not present as described, rep ace the timer.
27091 111598

18
WIRING SCHEM TICS
27103.0000C 11/98 © 1996
BUNN-O-MATIC CORPORATION
SCHEMATIC WIRING DIAGRAM
LPG2E
NL1
BLK
RED
WHI
120 VOLTS AC
2 WIRE
SINGLE PHASE
60 HZ
GRN
3
AMP
2
3
4
5
6
1
7
8
9
10
TIMER ASSY.
(Hopper Slide
Gate Timer
Dial Wiring)
Right - Brown
Left - Orange
YEL
WHI
BLU
YEL
WHI/BLK
BLK
RED
VIO
ORA
OFF/ON/START
SWITCH
RED
RED
RED
GRN
SELECTOR
SWITCH
WHI
RED
RED
WHI
BLK
GRINDER
SLIDE GATES
RT
SOL
LT
SOL
RED RED
M
27091 111598

19
BLK
WHI
RED
RED
10529.0000C 3/92 © 1990
BUNN-O-MATIC CORPORATION
SCHEMATIC WIRING DIAGRAM
LPG & LPG2
NL1
B
L
K
P1
2
3
4
5
6
1
RED
WHI/BLK
BLK
WHI/BLU
WHI/BRN
WHI
GRN
RED
WHI/BLK
BLK
WHI/BLU
WHI/BRN
WHI
BLK
RED
WHI/BRN
WHI/BLU
1
2
3
4
5
P2 BLK
RED
WHI/BRN
WHI/BLU
DC
MOTOR
BLK
WHI
RED
RED 4
1
2
3
P3
GREEN
3
AMP
TIMER
BLK W
H
I
120 VOLTS AC
2 WIRE
SINGLE PHASE
60 HZ
27091 111598

20
BLK
WHI
RED
RED
10529.0002E 8/01 © 1990
BUNN-O-MATIC CORPORATION
SCHEMATIC WIRING DIAGRAM
LPG-A
L2L1
B
L
K
P1
2
3
4
5
6
1
RED
WHI/BLK
BLK
WHI/BLU
WHI/BRN
WHI
GRN
RED
WHI/BLK
BLK
WHI/BLU
WHI/BRN
WHI
BLK
RED
WHI/BRN
WHI/BLU
1
2
3
4
5
P2 BLK
RED
WHI/BRN
WHI/BLU
DC
MOTOR
BLK
WHI
RED
RED 4
1
2
3
P3
GRN/YEL
3
AMP
TIMER
BLK R
E
D
230 VOLTS AC
2 WIRE
SINGLE PHASE
50/60 HZ
WIRING SCHEM TICS
27091 082701