manuals.online logo
Brands
  1. Home
  2. •
  3. Brands
  4. •
  5. Bunn
  6. •
  7. Coffee Maker
  8. •
  9. Bunn ST Instruction and safety manual

Bunn ST Instruction and safety manual

This manual suits for next models

5

Other Bunn Coffee Maker manuals

Bunn F-35 Instruction and safety manual

Bunn

Bunn F-35 Instruction and safety manual

Bunn ICB-TWIN Instruction Manual

Bunn

Bunn ICB-TWIN Instruction Manual

Bunn INFUSION SERIES ICB/TWIN Installation and operating manual

Bunn

Bunn INFUSION SERIES ICB/TWIN Installation and operating manual

Bunn TB3-LP Instruction Manual

Bunn

Bunn TB3-LP Instruction Manual

Bunn MCA Installation instructions

Bunn

Bunn MCA Installation instructions

Bunn CWT TWIN Instruction and safety manual

Bunn

Bunn CWT TWIN Instruction and safety manual

Bunn My Cafe AP Installation guide

Bunn

Bunn My Cafe AP Installation guide

Bunn A10 Automatic Owner's manual

Bunn

Bunn A10 Automatic Owner's manual

Bunn Single SH Instruction and safety manual

Bunn

Bunn Single SH Instruction and safety manual

Bunn Tiger Cool Froth Series User manual

Bunn

Bunn Tiger Cool Froth Series User manual

Bunn BX User manual

Bunn

Bunn BX User manual

Bunn My Cafe AP Troubleshooting guide

Bunn

Bunn My Cafe AP Troubleshooting guide

Bunn Pour-Omatic GR-8 Installation instructions

Bunn

Bunn Pour-Omatic GR-8 Installation instructions

Bunn DUAL / GPR-DBC Troubleshooting guide

Bunn

Bunn DUAL / GPR-DBC Troubleshooting guide

Bunn CDBC Instruction and safety manual

Bunn

Bunn CDBC Instruction and safety manual

Bunn Sure Immersion 220 Troubleshooting guide

Bunn

Bunn Sure Immersion 220 Troubleshooting guide

Bunn VP17-3 User manual

Bunn

Bunn VP17-3 User manual

Bunn G9 HD Instruction Manual

Bunn

Bunn G9 HD Instruction Manual

Bunn U3 Instruction and safety manual

Bunn

Bunn U3 Instruction and safety manual

Bunn PTD 4 Quick reference guide

Bunn

Bunn PTD 4 Quick reference guide

Bunn TB3Q User manual

Bunn

Bunn TB3Q User manual

Bunn 392 Manual

Bunn

Bunn 392 Manual

Bunn AutoPOD Installation guide

Bunn

Bunn AutoPOD Installation guide

Bunn SINGLE Troubleshooting guide

Bunn

Bunn SINGLE Troubleshooting guide

Popular Coffee Maker manuals by other brands

illy FrancisFrancis X7.1 user manual

illy

illy FrancisFrancis X7.1 user manual

Continental Electric CE23601 instruction manual

Continental Electric

Continental Electric CE23601 instruction manual

Electrolux EKF3 series Instruction book

Electrolux

Electrolux EKF3 series Instruction book

MIA KF 1740 instruction manual

MIA

MIA KF 1740 instruction manual

DeLonghi ECAM26455M Instructions for use

DeLonghi

DeLonghi ECAM26455M Instructions for use

Fagor CG-414 D Instructions for use

Fagor

Fagor CG-414 D Instructions for use

Somogyi Elektronic Home HG PR 14 instruction manual

Somogyi Elektronic

Somogyi Elektronic Home HG PR 14 instruction manual

Morphy Richards Accents Espresso MR47580 instructions

Morphy Richards

Morphy Richards Accents Espresso MR47580 instructions

Crux 14634 instruction manual

Crux

Crux 14634 instruction manual

Taurus Livorno 6 manual

Taurus

Taurus Livorno 6 manual

Delta-q QUICK instruction manual

Delta-q

Delta-q QUICK instruction manual

Chris Coffee Service Silvano owner's manual

Chris Coffee Service

Chris Coffee Service Silvano owner's manual

Black & Decker BLACK DECKER HOME DE790 Use and care book

Black & Decker

Black & Decker BLACK DECKER HOME DE790 Use and care book

Saeco Vienna Plus Sup 018M operating instructions

Saeco

Saeco Vienna Plus Sup 018M operating instructions

INCAPTO BXCO1470E Instructions for use

INCAPTO

INCAPTO BXCO1470E Instructions for use

Bosch TASSIMO finesse TAS16B Series user manual

Bosch

Bosch TASSIMO finesse TAS16B Series user manual

Exido 245-072 Specifications

Exido

Exido 245-072 Specifications

Animo OptiVend Choco user manual

Animo

Animo OptiVend Choco user manual

manuals.online logo
manuals.online logoBrands
  • About & Mission
  • Contact us
  • Privacy Policy
  • Terms and Conditions

Copyright 2025 Manuals.Online. All Rights Reserved.

OPERATING & SERVICE MANUAL
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 F X: (217) 529-6644
www.bunnomatic.com
29251.0000G 04/01 ©1998 Bunn-O-Matic Corporation
S,S
ST,ST
STF,STF
BUNN
®
Page 2
#00831.0000 #00 58.0000
USER NOTICES
29251 042301
W RR NTY
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 three 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 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, dealers or employees of Bunn are
not authorized to make modifications to this warranty or to make additional warranties that are binding on Bunn.
Accordingly, statements by such individuals, whether oral or written, do not constitute warranties and should not
be relied upon.
The Buyer shall give Bunn prompt notice of any claim to be made under this warranty by telephone at (217)
529- 01 or by writing to Post Office Box 3227, Springfield, Illinois, 2708-3227. If requested by Bunn, the Buyer
shall ship the defective equipment prepaid to an authorized Bunn service location. If Bunn determines, in its sole
discretion, that the equipment does not conform to the warranty, Bunn shall repair the equipment with no charge
for parts during the warranty period and no charge for labor by a Bunn Authorized Service Representative during
the warranty period. If Bunn determines that repair is not feasible, Bunn shall, at its sole option, replace 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 shall Bunn be liable for any other damage or loss, including, but not limited to, lost profits, lost sales,
loss of use of equipment, claims of Buyer’s customers, cost of capital, cost of down time, cost of substitute
equipment, facilities or services, or any other special, incidental or consequential damages.
Page 3
#00 5 .0000
USER NOTICES (Continued)
#00882.0000
#027 3.0000
#027 5.0000
#027 9.0000
29251 101598
Page 4
PLUMBING REQUIREMENTS
Models S & S :
These models are completely portable and require no attached plumbing.
Models ST, ST , STF & STF
These brewers must be connected to a cold water system with operating pressure between 20 and 90 psi (138
and 20 kPa) from a 1⁄2" or larger supply line. A shut-off valve should be installed in the line before the brewer. Install
a regulator in the line when pressure is greater than 90 psi ( 20 kPa) to reduce it to 50 psi (345 kPa). The water
inlet fitting is 1⁄4" flare.
NOTE - Bunn-O-Matic recommends 1⁄4" copper tubing for installations of less than 25 feet and 3⁄8" for more than
25 feet from the 1⁄2" water supply line. A tight coil of copper tubing in the water line will facilitate moving the brewer
to clean the countertop. Bunn-O-Matic does not recommend the use of a saddle valve to install the brewer. The
size and shape of the hole made in the supply line by this type of device may restrict water flow.
ELECTRIC L REQUIREMENTS
C UTION - The brewer must be disconnected from the power source until specified in
Initial Set-Up.
Model 15 has an attached cordset and requires 2-wire grounded service rated 120 volts ac, 15 amp, single
phase, 0 Hz.
Model 35 requires 3-
wire, grounded service
rated 120/208 or 120/240
volts ac, 20 amp, single
phase, 0 Hz. Proceed as
follows:
Model 20 requires 2-
wire, grounded service
rated 120 volts ac, 20
amp, single phase, 0 Hz.
Proceed as follows:
Electrical Hook-Up
C UTION – Improper electrical installation will damage electronic components.
1. An electrician must provide electrical service as specified.
2. Using a voltmeter, check the voltage and color coding of each conductor at the electrical source.
3. Before electrically connecting the brewer, remove the front and rear panel and rotate the thermostat knob fully
counterclockwise to the "OFF" position. Keep this knob in the "OFF" position until performing the "Initial Set-Up"
4. Feed the power cord through the strain relief and connect it to the terminal block.
5. Connect the brewer to the power source and verify the voltage at the terminal block before proceeding.
(Models S and ST-15 have cord attached. Replace all panels.
. If plumbing is to be hooked-up later be sure the brewer is disconnected from the power source. If plumbing
has been hooked-up, the brewer is ready for "Initial Set-Up".
NOTE: Schematic wiring diagrams are included in this manual.
“ " & "B” models re-
quire 2-wire, grounded
service rated 200 volts ac
or 240 volts ac, 20 amp,
single phase, 50 Hz. Pro-
ceed as follows:
"SDB” model requires
2-wire, grounded service
rated 100 volts ac, 20
amp, single phase, 50 Hz.
Proceed as follows:
This equipment must be installed to comply with the Basic Plumbing Code of the Building
Officials and Code dministrators International, Inc. (BOC ) and the Food Service Sanitation
Manual of the Food and Drug dministration (FD ).
29251 011800
P1841
L2 RED
NEUTRAL
L1 BLACK
120V A.C.
120V A.C.
208 or
240V.A.C.
WHITE
NEUTRAL
L1 BLACK 120V.A.C.
WHITE
NEUTRAL
L1 BLACK 100V.A.C.
WHITE
P2185 P2185
P2193
Page 5
INITI L SET-UP
C UTION - The brewer must be disconnected from the power source throughout the initial set-up, except when
specified in the instructions.
1. Insert an empty funnel into the funnel rails.
2. Place an empty dispenser under the funnel.
3. Remove the front or rear panel and turn the thermostat knob to the “OFF” position and connect the brewer
to the power source.
4. Fill the tank with water as directed:
4A. Models S & S :
Pour three pitchers of tap water into the screened area on top of the brewer. Allow approximately two minutes
between pitchers for water to flow into the tank. While the third pitcher of water is entering the tank, the tank
will fill to capacity and the excess will flow from the sprayhead, out of the funnel, and into the dispenser.
4B. Models ST, ST :
Connect the brewer to the power source, place the "ON/OFF" switch in the "ON" upper position, and
momentarily press and release the start switch. Water will begin flowing into the tank. When water stops
flowing into the tank, initiate a second and a third brew cycle. During the third brew cycle the tank will fill to
its capacity and the excess will flow from the sprayhead, out of the funnel, and into the dispenser.
4C. Models STF & STF
Brewers will fill automatically when lower ON/OFF switch is placed in the "ON" position and tank will fill to
capacity.
5. When the flow of water from the funnel stops, turn the thermostat knob to the “ON” position and wait
approximately twenty minutes for the water in the tank to heat to the proper temperature. Some water will
drip from the funnel during this time; this is due to expansion and should not occur thereafter.
. Empty the dispenser and initiate another brew cycle as directed:
A. Models S & S :
Pour one pitcher of tap water into the screened area on top of the brewer.
B. Models ST, STF, ST & STF :
Place the "ON/OFF" switch in the "ON" upper position, and momentarily press and release the start switch.
7. Place the "ON/OFF" switch in the lower “OFF” position after water has stopped flowing from the funnel, and
let the water in the tank reheat to the proper temperature.
8. Empty the dispenser and proceed as directed:
8A. Models S & S :
The brewer is now ready for use in accordance with the coffee brewing instructions on the next page.
8B. Models ST, STF, ST & STF :
Place the "ON/OFF" switch in the "ON" upper position, and momentarily press and release the start switch.
Check the water volume in the dispenser after water has stopped flowing from the funnel. It should be 4
ounces.
9. If not, disconnect the brewer from the power source. On early models remove the access panel. Adjust the
timer as required (see service section). Replace the panel, connect the brewer to the power source, and allow
the water to reheat, start, and measure another brew cycle.
10. Repeat step 9 until 4 oz water volume is achieved.
11. The brewer is now ready for use in accordance with the coffee brewing instructions on the next page.
29251 052500
Page
OPER TING CONTROLS
Models S & S :
These models function without operating controls.
Models ST, STF, ST & STF :
ON/OFF SWITCH
Placing the "ON/OFF" switch in the "OFF" lower position stops brewing. Stopping a brew cycle after it has been
started will not stop the flow of water into the funnel until the tank syphons down to its proper level. Placing the
switch in the "ON" upper position supplies power to the brew station warmer and enables the brew circuit and on
Models STF and STFA refills the tank.
ST RT SWITCH
Momentarily pressing and releasing the switch starts a brew cycle when the "ON/OFF" switch is in the "ON" upper
position.
NOTE – The "ON/OFF" switch must be in the "ON" upper position to initiate and complete a brew cycle.
COFFEE BREWING
1. Insert a BUNN® filter into the funnel.
2. Pour the fresh coffee into the filter and level the bed of grounds by gently shaking.
3. Slide the funnel into the funnel rails.
4. Place an empty dispenser beneath the funnel.
5. Operate the brewer as directed:
5A. Models S & S :
Pour one pitcher of tap water into the screened area on top of the brewer.
5B. Models ST, STF, ST & STF :
Place the "ON/OFF" switch in the "ON" upper position. Momentarily press and release the start switch.
. When brewing is completed, simply discard the grounds and filter.
CLE NING
1. The use of a damp cloth rinsed in any mild, non-abrasive, liquid detergent is recommended for cleaning all
surfaces on Bunn-O-Matic equipment.
2. Check and clean the sprayhead. The sprayhead holes must always remain open.
3. With the sprayhead removed, insert the deliming spring (provided) all the way into the sprayhead tube. When
inserted properly, no more than two inches of spring should be visible. Saw back and forth five or six times.
NOTE – In hard water areas, this may need to be done daily. It will help prevent liming problems in the brewer and
takes less than a minute.
29251 101598
Page 7
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 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 switch contact or a loose connection at a
terminal or crimp.
• Solenoid removal requires interrupting the water supply to the valve. Damage may result if solenoids are
energized for more than ten minutes without a supply of water.
• The use of two wrenches is recommended whenever plumbing fittings are tightened or loosened. This will help
to avoid twists and kinks in the tubing.
• Make certain that all plumbing connections are sealed and electrical connections tight and isolated.
• This brewer is heated at all times. Keep away from combustibles.
W RNING – • Exercise extreme caution when servicing electrical equipment.
• Unplug the brewer when servicing, except when electrical tests are specified.
• Follow recommended service procedures
• Replace all protective shields or safety notices
PROBLEM
Brew cycle will not start (ST, STF,
STA & STFA)
PROBABLE CAUSE
1. No water
2. No power or incorrect voltage to
the brewer
REMEDY
Water lines and valves to the brewer
must be open.
(A1) Check the terminal block for
120 volts across the black and
white terminals on two wire 120
volt brewers.
(A2) Check the terminal block for
120 volts across the red and white
terminals and the black and white
terminal on three wire 120/240
volt brewers.
(A3) Check the terminal block for
200 volts on Model STFB brewers
or 240 volts on "A Series" brewers
across the red and black termi-
nals.
(A4) Check the terminal block for
100 volts on Model SDB brewers
across the white and black termi-
nals.
(B) Check circuit breakers or fuses.
29251 101598
Page 8
TROUBLESHOOTING (cont.)
PROBLEM
Brew cycle will not start (cont.)
(ST, STF, STA & STFA)
Water is not hot
Inconsistent beverage level in dis-
penser
PROB BLE C USE
3. ON/OFF switch
4. Start switch
5. Timer
. Solenoid valve
7. Strainer/flow control (.222
GPM)
1. Limit thermostat
C UTION - Do not eliminate or
bypass limit thermostat. Use only
BOM replacement part #29329.
1000.
2. Control thermostat
3. Tank heater
1. Strainer /flow control (.222
GPM) (ST, STF, STA & STFA)
2. Liquid level board or level probe
REMEDY
Refer to
Service
- ON/OFF Switch
for testing. See page 17
Refer to
Service
- Start Switch for
testing procedures. See page 19
Refer to
Service
- Timer for testing
procedures. See page 22 or 24
Refer to
Service
- Solenoid Valve
for testing procedures. See page
18
(A) Direction of flow arrow must
be pointing towards brewer.
(B) Remove the strainer/flow con-
trol and check for obstructions.
Clear or replace.
Refer to
Service
- Limit Thermo-
stat for testing procedures. See
page 1
Refer to
Service
- Control Ther-
mostat for testing procedures. See
page 14
Refer to
Service
- Tank Heater for
testing procedures. See page 20
(A) Direction of flow arrow must
be pointing towards the brewer.
(B) Remove the strainer/flow con-
trol and check for obstruction.
Clear or replace.
Refer to
Service
- Liquid Level
Board for testing procedures. See
page 2
29251 052500
Page 9
TROUBLESHOOTING (cont.)
PROBLEM
Inconsistent beverage level in dis-
penser (cont.)
Consistently low beverage level in
the dispenser (ST, STF, STA &
STFA)
Spitting or excessive steaming
PROB BLE C USE
3. Syphon system
4. Lime build-up
C UTION - Tank and tank compo-
nents should be delimed regularly
depending on local water condi-
tions. Excessive mineral build-up
on stainless steel surfaces can ini-
tiate corrosive reactions resulting
in serious leaks.
5. Water pressure (ST, STF, STA
& STFA)
1. Timer
2. Strainer/flow control (.222
GPM)
1. Lime build-up
C UTION - Tank and tank compo-
nents should be delimed regularly
depending on local water condi-
tions. Excessive mineral build-up
on stainless steel surfaces can ini-
tiate corrosive reactions resulting
in serious leaks.
2. Control thermostat
REMEDY
The brewer must be level or slightly
lower in front to syphon properly.
Inspect the tank assembly for ex-
cessive lime deposits. Delime as
required.
The water pressure to the brewer
must be at least 20 psi (138 kPa).
(A) Early models-Timer dial must
indicate at least two minutes and
fifteen seconds.
(B) Refer to
Service
- Digital Timer
for testing procedures. See page
24
(A) Direction of flow arrow must
be pointing towards brewer.
(B) Remove the strainer/flow con-
trol and check for obstructions.
Clear or replace.
Inspect tank assembly for exces-
sive lime deposits. Delime as re-
quired.
Refer to
Service
- Control Ther-
mostat for testing procedures. See
page 14
29251 052500
Page 10
TROUBLESHOOTING (cont.)
PROBLEM
Dripping from sprayhead
Water flows into tank continuously
(ON/OFF Switch "ON")
Water flows into tank continuously
(ON/OFF Switch "OFF")
Beverage overflows dispenser
PROB BLE C USE
1. Syphon system
2. Lime build-up
C UTION - Tank and tank compo-
nents should be delimed regularly
depending on local water condi-
tions. Excessive mineral build-up
on stainless steel surfaces can ini-
tiate corrosive reactions resulting
in serious leaks.
3. Solenoid valve (ST, STF, STA &
STFA)
1. Timer (ST, STF, STA & STFA)
2. Start switch
3. Liquid level board
4. Relay
1. Solenoid valve (ST, STF, STA &
STFA)
1. Dispenser
2. Timer (ST, STF, STA & STFA)
REMEDY
The brewer must be level or slightly
lower in front to syphon properly.
Inspect the tank assembly for ex-
cessive lime deposits. Delime as
required.
Remove the solenoid valve and
clear any obstructions. Rebuild or
replace the valve if necessary.
See page 18
Refer to
Service -
Timer for testing
procedures. See page 22 or 24
Refer to
Service
- Start Switch for
testing procedures. See page 19
Refer to
Service
- LiquidLevel
Board for testing procedures. See
page 2
Refer to
Service
- Relay for testing
procedures. See page 28
Remove the Solenoid Valve and
clean any obstruction. Rebuild or
replace the valve if necessary. See
page 18
The dispenser must be completely
empty before starting a brew cycle.
Refer to
Service -
Timer for testing
procedures. See page 22 or 24
29251 052500