Bunn 1SH, 2SH User Manual

BUNN

®

1SH & 2SH

STAND

OPERATING & SERVICE MANUAL

BUNN-O-MATIC CORPORATION

POST OFFICE BOX 3227

SPRINGFIELD, ILLINOIS 62708-3227

PHONE: [phone] FAX: [phone]

28342.0000D 8/00 ©1997 Bunn-O-Matic Corporation

WARRANTY

Bunn-O-Matic Corp. (“Bunn”) warrants the equipment manufactured by it to be commercially free from defects
in material and workmanship existing at the time of manufacture and appearing within one year from the date of
installation. In addition:

1.) Bunn warrants electronic circuit and/or control boards to be commercially free from defects in material and

workmanship for two years from the date of installation.

2.) Bunn warrants the compressor on refrigeration equipment to be commercially free from defects in material

and workmanship for two years from the date of installation.

3.) Bunn warrants that the grinding burrs on coffee grinding equipment will grind coffee to meet original factory

screen sieve analysis for three years from date of installation or for 30,000 pounds of coffee, whichever comes first.

This warranty does not apply to any equipment, component or part that was not manufactured by Bunn or that,
in Bunn’s judgement, has been affected by misuse, neglect, alteration, improper installation or operation, improper
maintenance or repair, damage or casualty.

THE FOREGOING WARRANTY IS EXCLUSIVE AND IS IN LIEU OF ANY OTHER WARRANTY, WRITTEN OR
ORAL, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF EITHER
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. The agents, dealers or employees of Bunn are

not authorized to make modifications to this warranty or to make additional warranties that are binding on Bunn.

USER NOTICES

The notice on the stands should be kept in good condition. Replace if unreadable or damaged.

00986.0000

Page 2

ELECTRICAL REQUIREMENTS

The stands have an attached cordset and requires 2-wire grounded service rated 120 volts ac, single phase,
90 watts total for the 1SH, 180 watts total for the 2SH, or 2-wire grounded service rated 230 volts ac, single phase,
90 watts total for the 1SH, 180 watts total for the 2SH.

CLEANING

The use of a damp cloth rinsed in any mild, nonabrasive, liquid detergent is recommended for cleaning all
surfaces on Bunn-O-Matic equipment.

TROUBLESHOOTING

A troubleshooting guide is provided to suggest probable causes and remedies for the most likely problems
encountered. If the problem remains after exhausting the troubleshooting steps, contact the Bunn-O-Matic
Technical Service Department.

• Inspection, testing, and repair of electrical equipment should be performed only by qualified service
personnel.

• All electronic components have 120 - 240 volt ac and low voltage dc potential on their terminals.
Shorting of terminals or the application of external voltages may result in board failure.

• Intermittent operation of electronic circuit boards is unlikely. Board failure will normally be
permanent. If an intermittent condition is encountered, the cause will likely be a contact or a loose
connection at a terminal or crimp.

WARNING

• Exercise extreme caution when servicing electrical equipment.

• Disconnect power source when servicing, except when electrical tests are specified.

• Follow recommended service procedures.

• Replace all protective shields or safety notices.

Problem

Server will not heat

Probable Cause

1. No power or incorrect voltage.

2. Circuit breaker

3. Receptacle contact

4. Transformer

5. Rectifier

Remedy

Be sure the stand is connected to
the power source.

A) Check and reset if necessary

B) Refer to

for test procedures. See page 4

Clean or replace. See page 5

Refer to
test procedures. See page 7

Refer to
procedures. See page 6

Service -

Service

Service

Circuit breaker

- Transformer for

- Rectifier for test

Page 3

28342 071599

SERVICE

This section provides procedures for testing and
replacing various major components used in these
stands should service become necessary. Refer to

Troubleshooting

cause of any problem.

WARNING - Inspection, testing, and repair of electri­cal equipment should be performed only by qualified
service personnel. The stands should be unplugged
when servicing, except when electrical tests are re­quired and the test procedure specifically states to
connect the stand to the power source.

COMPONENT ACCESS

WARNING - Disconnect the stand from the power

source before the removal of any panel or the replace­ment of any component.

All components are accessible by the removal of
the receptacle cover and the stand cover.

for assistance in determining the

CIRCUIT BREAKER

FIG. 1 COMPONENT ACCESS

FIG. 2 CIRCUIT BREAKER

P1402

Location

The circuit breaker(s) is located on the upper
part of the receptacle bracket just above the spring
contact receptacle(s) assembly.

P1402

Page 4

SERVICE (cont.)

Test Procedures

1. Disconnect the stand from the power source.

2. Remove the wires from the circuit breaker.

3. Check for continuity between the circuit breaker
terminals. Continuity must be present between the
terminals.

If continuity is present as described the circuit breaker
is functioning properly.
If continuity is not present as described, press reset
button and repeat step #3, if continuity is not present
as described, replace the circuit breaker.

Removal and Replacement:

1. Remove the wires from the circuit breaker.

2. Compress the clips on the back side of the recep­tacle bracket and gently push the circuit breaker
through the opening in the receptacle bracket.

3. Push the new circuit breaker into the opening in
the receptacle bracket until the clips snap into
position.

4. Reconnect the wires to the circuit breaker.

5. Refer to Fig. 3 when reconnecting the wires.

BLU/BLK to Transformer #12

RECEPTACLE ASSEMBLY (SPRING CONTACT)

P1402

FIG. 4 RECEPTACLE ASSEMBLY

Location:

The receptacle assembly is located on the lower
front of the receptacle bracket just below the circuit
breaker.

BLU/BLK to Rectifier "AC"

FIG. 3 CIRCUIT BREAKER TERMINALS

P1330

Test Procedures:

1. Clean or replace spring contacts.

Removal and Replacement:

1. Disconnect the stand from the power source.

2. Disconnect the wires from the receptacle assem-

bly.

3. Remove the two #6-32 flat head screws securing

the receptacle to the receptacle bracket.

4. Remove and discard receptacle.

5. Install new receptacle in the receptacle bracket

and secure with two #6-32 flat head screws..

6. Refer to Fig. 5 and reconnect the wires.

BLK to (-) Terminal on Rectifier

RED to (+) Terminal on Rectifier

Page 5

FIG. 5 RECEPTACLE TERMINALS

P1380

28342 091597

SERVICE (cont.)

+

A

C

A

C

1 2 3 4 5 6

RECTIFIERS (cont.)

RECTIFIER

Removal and Replacement:
1 Disconnect the wires from the rectifier.

2. Remove the #6-32 truss head screw securing the
rectifier to the stand housing.

3. Remove the rectifier and discard.

4. Install new rectifier in the stand housing and
secure with a #6-32 truss head screw.

6
5
4

3
2

1

5. Refer to Fig 7 and reconnect the wires.

FIG. 6 RECTIFIER

P1403.40

Location:

The rectifier(s) is located inside on the right side of
the stand housing just to the right of the transformer
for 1SH Stand and on the right and left side of the stand
housing for 2SH Stand.

Test Procedures:

1. Disconnect the stand from the power source.

2. Remove the red wire and the black wire from the

rectifier.

3. Check the voltage across the (+) and (-) terminals

on the rectifier with a voltmeter. Connect the stand

to the power source. The indication must be 24

volts dc.

4. Disconnect the stand from the power source.

If voltage is present as described, the rectifier is
operating properly.
If voltage is not present as described, refer to the stand
wiring diagrams and check the stand wiring harness.

Page 6

FIG. 7 RECTIFIER TERMINALS

P1381

SERVICE (cont.)

1 2 3 4 5 6

1 2 3 4 5 6

1 2 3 4 5 6

TRANSFORMER

5. Disconnet the blue/black wires from terminals #7
and #12 on the transformer.

6. Check the voltage across terminal #7 and #12 of
the transformer with a voltmeter. Connect the
stand to the power source. The indication must be
24 volts ac.

6
5

4
3
2
1

6

5

4
3

2
1

6
5
4

3
2
1

FIG. 8 TRANSFORMER

If voltage is present as described the transformer is
operating properly.
If voltage is not present as described, replace the
transformer.

Removal and Replacement:

1. Disconnect all the wires from the transformer.

2. Remove the four #6-32 screws securing the trans­former and mounting strap to the stand housing.

3. Remove transformer and discard.

4. Install new transformer in the stand housing se­curing with four #6-32 screws and mounting strap.

5. Refer to Fig. 9 when reconnecting the wires.

P1403.40

Location:

The transformer(s) is located in the stand housing

on the base plate.

Test Procedures:

1. Disconnect the stand from the power source.

2. Disconnect the black wire from terminal #5 and the
white or red wire from terminal # 6.

3. Check the voltage across the black and white or red
wire with a voltmeter. Connect the stand to the
power supply. The indication must be:
a.) 120 volts ac for two wire 120 volt models.
b.) 200 to 240 volts ac for two wire 200 or 240 volt
models.

4. Disconnect the stand from the power supply.

If voltage is present as described reconnect the wires
and proceed to #5.
If voltage is not present as described, refer to the
wiring diagrams and check the stand wiring harness.

Page 7

28342 061598

SERVICE (cont.)

TRANSFORMER (cont.)

Page 8

SCHEMATIC WIRING DIAGRAM

NL1

BLK

WHI

120 VOLTS AC, 2 WIRE

SINGLE PHASE

NL1

BLK

WHI

120 VOLTS AC, 2 WIRE

SINGLE PHASE

GRN

GRN

WHI

BLK

1 SH STAND

TRANSFORMER

BLU/BLK BLU/BLK

1

2

5

6

SCHEMATIC WIRING DIAGRAM

TRANSFORMER

1

2

5

6

TRANSFORMER

1

2

5

6

12

7

12

7

12

7

2 SH STAND

BLU/BLK BLU/BLK

BLU/BLK

4

AMP

4

AMP

4

AMP

BLU/BLK

–

+

Front view of Server Contacts

24VDC

+

–

AC

RECT

+

BLU/BLKBLU/BLK

AC

RECT

+

AC

BLU/BLKBLU/BLK

AC

RECT

+

AC

BLU/BLKBLU/BLK

BLK

–

AC

Front view of Server Contacts

24VDC

–

BLK

–

RED

BLK

–

RED

RED

–

+

24VDC

+

+

–

Page 9

28342 071599

SCHEMATIC WIRING DIAGRAM

L2 L1

BRN

BLU

230 VOLTS AC, 2 WIRE

SINGLE PHASE

27789.0001D 11/98 © 1997 BUNN-O-MATIC CORPORATION

GRN/YEL

TRANSFORMER

1

2

BLK

5

6

1 SH STAND, 230V CE

BLU/BLK BLU/BLK

12

11

4

AMP

RESETTABLE

8

FUSE

7

–

+

Front view of Server Contacts

24VDC

+

–

AC

BLK

–

RED

AC

RECT

+

BLU/BLKBLU/BLK

L2 L1

BRN

BLU

230 VOLTS AC, 2 WIRE

SINGLE PHASE

27793.0001C 11/98 © 1997 BUNN-O-MATIC CORPORATION

GRN/YEL

BRN/BLK

BLU

BLK

BLK

1

2

5

6

1

2

5

6

SCHEMATIC WIRING DIAGRAM

2 SH STAND, 230V CE

TRANSFORMER

TRANSFORMER

BLU/BLK BLU/BLK

12

11

RESETTABLE

FUSE

8

BLU/BLK

7

BLU/BLK

12

11

RESETTABLE

FUSE

8

7

AMP

AMP

–

+

Front view of Server Contacts

4

AC

RECT

+

AC

BLU/BLK

4

BLU/BLK

AC

RECT

+

AC

BLU/BLKBLU/BLK

24VDC

–

BLK

–

RED

BLK

–

RED

24VDC

+

+

–

Page 10

28342 071599