TB3
TB3-LP
OPERATING & SERVICE MANUAL
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 FAX: (217) 529-6644
37235.0000D 05/06 ©2004 Bunn-O-Matic Corporation www.bunn.com
CONTENTS
Introduction .....................................................................2
Warranty ..........................................................................2
User Notices .....................................................................3
Electrical & Plumbing Requirements ............................... 4
Initial Set-Up ....................................................................5
Adjusting Brew Volumes .................................................. 6
Auto Sweetener Set-up .................................................... 6
Operating Controls ...........................................................7
Cleaning ...........................................................................8
Auto Sweetener Cleaning .................................................8
Tea Brewing ...................................................................... 8
Troubleshooting ............................................................... 9
Service ...........................................................................15
Wiring Diagrams ............................................................28
INTRODUCTION
This equipment will brew a three-gallon batch of fresh tea into an awaiting dispenser. The tea will be dispensed at
approximately room temperature to conserve ice. The brewer is only for indoor use on a sturdy counter or shelf.
BUNN-O-MATIC COMMERCIAL PRODUCT WARRANTY
Bunn-O-Matic Corp. (“BUNN”) warrants equipment manufactured by it as follows:
1) All equipment other than as specifi ed below: 2 years parts and 1 year labor.
2) Electronic circuit and/or control boards: parts and labor for 3 years.
3) Compressors on refrigeration equipment: 5 years parts and 1 year labor.
4) Grinding burrs on coffee grinding equipment to grind coffee to meet original factory screen sieve analysis: parts and
labor for 3 years or 30,000 pounds of coffee, whichever comes fi rst.
These warranty periods run from the date of installation BUNN warrants that the equipment manufactured by it will be
commercially free of defects in material and workmanship existing at the time of manufacture and appearing within the
applicable warranty period. This warranty does not apply to any equipment, component or part that was not manufactured
by BUNN or that, in BUNN’s judgment, has been affected by misuse, neglect, alteration, improper installation or operation,
improper maintenance or repair, damage or casualty. This warranty is conditioned on the Buyer 1) giving BUNN prompt
notice of any claim to be made under this warranty by telephone at (217) 529-6601 or by writing to Post Offi ce Box 3227,
Springfi eld, Illinois 62708-3227; 2) if requested by BUNN, shipping the defective equipment prepaid to an authorized BUNN
service location; and 3) receiving prior authorization from BUNN that the defective equipment is under warranty.
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 modifi cations 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.
If BUNN determines in its sole discretion that the equipment does not conform to the warranty, BUNN, at its exclusive
option while the equipment is under warranty, shall either 1) provide at no charge replacement parts and/or labor (during
the applicable parts and labor warranty periods specifi ed above) to repair the defective components, provided that this
repair is done by a BUNN Authorized Service Representative; or 2) shall replace the equipment or refund the purchase
price for the equipment.
THE BUYER’S REMEDY AGAINST BUNN FOR THE BREACH OF ANY OBLIGATION ARISING OUT OF THE SALE OF THIS
EQUIPMENT, WHETHER DERIVED FROM WARRANTY OR OTHERWISE, SHALL BE LIMITED, AT BUNN’S SOLE OPTION
AS SPECIFIED HEREIN, TO REPAIR, REPLACEMENT OR REFUND.
In no event shall BUNN be liable for any other damage or loss, including, but not limited to, lost profi ts, 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 2
37235 050205
USER NOTICES
Carefully read and follow all notices on the equipment and in this manual. They were written for your protection. All notices on the equipment should be kept in good condition. Replace any unreadable or damaged
#00831.0000
#37881.0000
#00656.0000
#06064.0000
WARNING
• FILL WATER TANK
BEFORE ENERGIZING
• DO NOT OVERLOAD
CIRCUIT
• KEEP AWAY FROM
COMBUSTIBLES
• DO NOT DEFORM
PLUG OR CORD
SEE
INSTRUCTIONS
• FAILURE TO COMPLY
RISKS EQUIPMENT
DAMAGE, FIRE OR
SHOCK
• BREWER ENERGIZED
UNLESS UNPLUGGED
#03408.0000
#03409.0000
BREWERS
CAUTION – Disconnect the power source from the brewer prior to the removal
of any panel for the replacement or adjustment of any component.
NOTE: Check that the brewer is connected to water supply, the tank is properly
filled, and a funnel and server are in place, prior to setting or modifying batch
sizes.
1. Modifying batch sizes. To modify a batch volume, first check that the SET/
LOCK switch is in the “SET” position on the circuit board. If the brewer has
a batch selector switch, position it to the size to be changed.
To increase a batch size, Press and hold the START or BREW switch until
three clicks are heard. Release the switch and then press it again one or
more times. Each time the switch is pressed, two seconds are added to the
brew time period. Allow the brew cycle to finish in order to verify that the
desired volume has been achieved.
To decrease a batch size, Press and release the START or BREW switch
once for every two-second interval to be removed from the total brew time
period; then immediately press and hold down the START or BREW switch
until three clicks are heard. Release the switch. Allow the brew cycle to
finish in order to verify that the desired volume has been achieved.
2. Setting batch sizes. To set a batch volume, first check that the SET/LOCK
switch is in the “SET” position on the circuit board. Press and hold the
START or BREW switch until three distinct clicks are heard (this will take
approximately ten seconds), and then release the switch. (Failure to release the switch within two seconds from the third click causes the volume
setting to be aborted). View the level of the liquid being dispensed. When
the desired level is reached, turn the ON/OFF switch to “OFF”. The brewer
remembers this volume and will continue to brew batches of this size until
the volume setting procedure is repeated. Empty server(s), turn selector
switch to positions that have yet to be set, and repeat batch setting procedure until all batch sizes are set.
NOTE: When brewing coffee, batch volumes will decrease due to absorption by
TIMER SETTING
Page 3
37235 050205
ELECTRICAL REQUIREMENTS
CAUTION - The brewer must be disconnected from the power source until specifi ed in Initial Set-Up.
120V model brewers require 2-wire, grounded service rated 120 volts ac, 15 amp, single phase, 60 Hz.
"A" model brewers require 2-wire, grounded service rated 230 volts ac, 10 amp, single phase, 50 Hz.
"B" model brewers require 2-wire, grounded service rated 100 volts ac, 15 amp, single phase, 60 Hz.
WARNING - If the power cord is ever damaged, it must be replaced by the manufacturer or its service agent with
a special cord available from the manufacturer or its service agent in order to avoid a hazard.
Proceed as follows:
Electrical Hook-Up
CAUTION – Improper electrical installation will damage electronic components.
1. An electrician must provide electrical service as specifi ed.
2. Using a voltmeter, check the voltage and color coding of each conductor at the electrical source.
3. Remove top cover from the brewer.
4. Rotate the control thermostat knob fully counterclockwise to the "OFF" position and replace the top cover.
5. Connect the brewer to the power source.
6. 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.
PLUMBING REQUIREMENTS
These brewers must be connected to a cold water system with operating pressure between 20 (138) and 90
psi (620 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 (620 kPa) to reduce it to 50 psi (345 kPa). The
water inlet fi tting is 1⁄4" fl are.
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 fl ow.
This equipment must be installed to comply with the Basic Plumbing Code of the Building Offi cials
and Code Administrators International, Inc. (BOCA) and the Food Service Sanitation Manual of the
Food and Drug Administration (FDA). For models installed outside the U.S.A., you must comply with
the applicable Plumbing/Sanitation Code for your area.
1. Remove the shipping cap from the bulkhead fi tting on the rear of the brewer.
2. Flush the water line and securely attach it to the bulkhead fi tting on the rear of the brewer.
3. Turn on the water supply.
NOTE: TheFlow Control/Strainer assembly is internal, located inside the back panel.
Page 4
37235 050506
INITIAL SET-UP
CAUTION - The brewer must be disconnected from the power source throughout the initial set-up, except when
specifi ed in the instructions.
1. Remove the top lid from the brewer.
2. Rotate the control thermostat knob fully counterclockwise to the "OFF" position and replace the top lid.
3. Set the delay knob of the timer on the right side of the hood at eight minutes and the dilution knob of the
timer on the right side of the hood at three minutes and forty-fi ve seconds.
4. Remove the metal discharge tip from the funnel to speed up the set-up procedure. Insert the empty funnel
into the funnel rails.
5. Place an empty dispenser on the brewer base. Be sure the funnel discharge is directly above the hole in the
dispenser top lid.
6. Plug in the brewer and place the ON/OFF switch in the "ON" position. Momentarily press the start switch.
Water will fl ow into the tank and will shut off after three minutes. Press the start switch again. During the
second period, the tank will fi ll to its capacity and the excess will fl ow from the funnel into the dispenser.
7. Place the ON/OFF switch in the "OFF" position.
8. Disconnect the brewer from the power source and remove the top lid.
Page 5
37235 050205
INITIAL SET-UP (cont.)
21. When all water stops fl owing, check the water volume in the dispenser. It should be 396 ounces.
22. If not, unplug the brewer and remove the top lid.
23. Adjust the dilution knob of the timer on the right side of the hood as required. Replace the top lid, plug in
the brewer, start, and measure another brew cycle.
24. Repeat steps 20-23 until the proper water volume is achieved.
25. Return the delay knob of the timer on the right side of the hood to eight minutes. Replace the top lid and
plug in the brewer.
26. Reinstall the metal discharge tip into the funnel.
27. Load the funnel with a BUNN® paper fi lter and approximately four ounces of loose tea leaves.
28. Place the ON/OFF switch in the "ON" position, momentarily press the start switch, and allow both the concentrate and dilution cycles to occur. Observe the funnel discharge and the dilution streams near the end of
the brew cycle. The dilution stream should stop approximately thirty seconds after the funnel discharge has
stopped.
29. If not, unplug the brewer and remove the top lid.
30. Adjust the delay knob of the timer on the right side of the hood as required. Replace the top lid and plug in
the brewer.
31. Repeat steps 27-30 until the proper dilution timing is achieved.
ADJUSTING BREW VOLUMES
CAUTION - Disconnect the power source from the brewer prior to the removal of any panel for the replacement
or adjustment of any component.
NOTE: Prior to setting or modifying batch sizes, check that the brewer is connected to water supply, the tank is
properly fi lled, and a funnel and server are in place.
1. Modifying batch sizes. To modify a batch volume, fi rst check that the SET/LOCK switch is in the "SET" posi-
tion on the circuit board.
To increase a batch size. Press and hold the START or BREW switch until three clicks are heard. Release
the switch (Failure to release the switch within two seconds after the third click causes the volume setting to
be aborted and previous volume setting will remain in memory) and press it again one or more times. Each
time the switch is pressed, two seconds are added to the brew time period. Allow the brew cycle to fi nish in
order to verify that the desired volume has been achieved.
To decrease a batch size. Press and release the START or BREW switch once for every two-second interval
to be removed from the total brew time period; then immediately press and hold down the START or BREW
switch until three clicks are heard. Release the switch. (Failure to release the switch within two seconds after
the third click causes the volume setting to be aborted and previous volume setting will remain in memory).
Allow the brew cycle to fi nish in order to verify that the desired volume has been achieved.
2. Setting batch sizes. To set a batch volume, fi rst check that the SET/LOCK switch is in the "SET" position on
the circuit board. Press and hold the START or BREW switch until three distinct clicks are heard, and then
release the switch. (Failure to release the switch within two seconds after the third click causes the volume
setting to be aborted and previous volume setting will remain in memory). View the level of the liquid being
dispensed. When the desired level is reached, turn the ON/OFF switch to "OFF" (lower). The brewer remembers
this volume and will continue to brew batches of this size until the volume setting procedure is repeated.
NOTE: When brewing tea, batch volumes will decrease due to absorption by the tea grounds.
3. Setting programming disable feature. If it becomes necessary to prevent anyone from changing brew times
once programmed, you can set the SET/LOCK switch to the "LOCK" position. This will prevent any programming to be done until switch is once again placed in the "SET" position.
Page 6
37235 050205
AUTO SWEETENER SET-UP
CAUTION - The brewer must be disconnected from the power source throughout the Initial Set-Up, except
when specifi ed in the instructions.
1. Remove the top lid and rear panel.
2. Make sure the brewer water supply is off.
3. Connect sweetener hose from the bag in a box delivery system to the rear fi tting marked "Sweetener" .
IMPORTANT - System delivery pressure must be regulated between 30-40 psi. System also needs to deliver
product for at least 4 minutes without shutting off. Some pump systems shut off after a few minutes of continuous running.
4. Set the "Delay knob on the dilution timer to the 3 minute setting. (The minimum delay setting)
5. Plug brewer into the power source.
6. Place an empty reservoir under the dilution nozzle of the brewer.
7. Close the adjustment valve on the rear of the brewer fully (clockwise), then open (counterclockwise) 1/2
turn.
8. Set the selector switch to the "Sweetened" side and press the "Start" switch momentarily. (After approximately
3 minutes the sweetener will come out of the dilution nozzle.)
9. Run sweetener for 1 minute, then set selector switch to the "Off" position. The fl ow will stop.
10. Measure the amount of sweetener dispensed and calculate if the volume needs to be increased or decreased
(Dilution cycle is usually between 3 to 3 1/2 minutes).
11. If adjustment is needed, turning the adjustment valve clockwise decreases the amount of sweetener dis-
pensed and turning the adjustment valve counterclockwise increases the amount of sweetener dispensed.
12. Set the "Delay" knob on the dilution timer back to the 6 to 7 minute setting.
13. After the desired volume has been set, turn the water supply on.
14. Reinstall the top lid and rear panel.
The brewer may now be returned to service.
OPERATING CONTROLS
A. ON/OFF Switch
ON - Placing the switch in the left position allows the start switch to activate a timed brew cycle for three gallons
of tea.
OFF - Placing the switch in the right position stops the brew cycle. Stopping a brew cycle after it has been started
will not stop the fl ow of water into the funnel until the tank syphons down to its proper level. The switch should
always be placed in this position after a brew cycle and whenever the brewer is unattended.
B. Start Switch
Starts a brew cycle when the ON/OFF switch is in the "ON" position.
C. UNSWEET/OFF/SWEET Selector Switch (Models with Sweetener Only)
UNSWEET - Placing the switch in the left positional allows the start switch to activate a timed brew cycle for
three gallons of tea without sweetener.
OFF - Placing the switch in the middle position stops the brew cycle. Stopping a brew cycle after it has been
started will not stop the fl ow of water into the funnel until the tank syphons down to its proper level. The switch
should always be placed in this position after a brew cycle and whenever the brewer is unattended.
SWEET - Placing the switch in the right positional allows the start switch to activate a timed brew cycle for three
gallons of tea with sweetener.
Page 7
37235 050205
CLEANING
CAUTION - CLEAN AND SANITIZE YOUR ICED TEA BREWER DAILY
1. Remove and thoroughly clean the entire brew funnel. The funnel tip and screen must be free from any tea
particles or residue. Reassemble the funnel.
2. Place the ON/OFF switch in the "OFF" position. Remove and thoroughly rinse the sprayhead. The holes must
be open and clear of any mineral deposits. Wipe the sprayhead panel clean with a damp cloth.
3. Insert the deliming spring into the sprayhead fi tting until no more than two inches is visible and move it in
and out 5 or 6 times. Insert the spring into the airvent hole in the sprayhead panel and move it in and out 5
or 6 times. Reattach the sprayhead.
4. Wash the entire outside surface of the brewer with a clean damp cloth.
CAUTION - DO NOT KEEP BREWED ICED TEA OVERNIGHT. THE SERVER MUST BE CLEANED DAILY.
AUTO SWEETENER CLEANING
1. Remove the connector off of the bag in a box.
2. Place the end in a bucket of hot water (120°-130°F)
3. Place an empty reservoir on the base under the dilution nozzle.
4. Set the selector switch to the "Sweetened" setting.
5. Press and release the "Start" switch.
6. Run three brew cycles in a row, emptying the reservoir after each cycle.
7. When the three cycles have been completed, hook the connector back up to the bag in a box system. (This
will keep buildup from occurring in the system.)
This procedure should be performed weekly or as needed to keep the system clear.
TEA BREWING
1. Begin each brew cycle with a clean empty brew funnel and server. (Be sure the server lid doesn’t interfere
with the fl ow of dilution water.)
2. Insert a BUNN® fi lter into the funnel.
3. Pour the packet of loose fresh tea leaves into the fi lter. Approximately four ounces is recommended.
4. Level the bed of tea leaves by gently shaking.
5. Slide the funnel into the funnel rails until it stops.
6. Place the ON/OFF switch in the "ON" position.
7. Momentarily press the start switch.
CAUTION - The funnel contains hot liquids. Remove funnel slowly.
8. Carefully remove the brew funnel and discard the used fi lter when tea no longer drips from the funnel tip.
9. Place the ON/OFF switch in the "OFF" position to prevent a false start.
10. Fresh tea is available at the faucet.
Page 8
37235 080204
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 qualifi ed service person-
nel.
• 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 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 fi ttings 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.
WARNING –
• Exercise extreme caution when servicing electrical equipment.
• Unplug the brewer when servicing, except when electrical tests are specifi ed.
• Follow recommended service procedures
• Replace all protective shields or safety notices
Problem
Brew cycle will not start
Probable Cause
1. No water
2. No power or incorrect voltage to
the brewer
3. Strainer/Flow Control
(.750GPM)
Remedy
Water lines and valves to the brewer
must be open.
Check circuit breakers or fuses.
(A) Direction of fl ow arrow must be
pointing upwards in the brewer.
(B) Remove the strainer/fl ow control and check for obstructions.
Clear or replace.
Page 9
37235 050205
TROUBLESHOOTING (cont.)
PROBLEM
Brew cycle will not start (cont.)
PROBABLE CAUSE
4. ON/OFF Switch
5. Start Switch
6. Brew Timer
7. Brew Solenoid Valve
8. Internal Flow control (.195
GPM)
REMEDY
Refer to Service - ON/OFF Switch
for testing. See page 24
Refer to Service - Start Switch for
testing procedures. See page 23
Refer to Service - Brew Timer for
testing procedures. See page 18
Refer to Service - Brew Solenoid
Valve for testing procedures. See
page 16
(A) Direction of fl ow arrow must be
pointing towards check valve.
(B) Remove the fl ow control and
check for obstructions. Clear or
replace.
Water is not hot
Dilution cycle will not start
1. Limit Thermostat
CAUTION - Do not eliminate or
bypass limit thermostat or thermal
cut-off. Use only BOM replacement
part 29329.0001
2. Control Thermostat
3. Tank Heater
1. ON/OFF Switch
2. Start Switch
Refer to Service - Limit Thermostat
for testing procedures. See page
22
Refer to Service - Control Thermostat for testing procedures. See
page 17
Refer to Service - Tank Heater for
testing procedures. See page 27
Refer to Service - ON/OFF Switch
for testing procedures. See page
24
Refer to Service - Start Switch for
testing procedures. See page 23
3. Dilution Timer
Page 10
Refer to Service - Dilution Timer for
testing procedures. See page 21
37235 080204
TROUBLESHOOTING (cont.)
PROBLEM
Dilution cycle will not start (cont.)
Inconsistent beverage level in
dispenser
PROBABLE CAUSE
4. Dilution Solenoid Valve
1. Internal Flow Control (.195
GPM)
2. Syphon System
3. Lime Build-up
CAUTION - Tank and tank components should be delimed regularly
depending on local water conditions. Excessive mineral build-up
on stainless steel surfaces can
initiate corrosive reactions resulting
in serious leaks.
REMEDY
Refer to Service - Dilution Solenoid
Valve for testing procedures. See
page 20
(A) Direction of fl ow arrow must be
pointing towards the check valve.
(B) Remove the fl ow control and
check for obstruction. Clear or
replace.
The brewer must be level or slightly
lower in front to syphon properly.
Inspect the tank assembly for excessive lime deposits. Delime as
required.
Consistently high or low beverage
level in the dispenser
4. Water Pressure
1. Brew Timer/Delay Timer
2. Strainer/Flow Control
(.750GPM)
The water pressure to the brewer
must be at least 20 psi (138 kPa).
With the ON/OFF switch "ON" adjust
the brew timer to achieve the recommended 76 oz. of concentrate
then the dilution timer to achieve a
total of 396 oz. for each three-gallon brew cycle.
(A) Direction of fl ow arrow must be
pointing upwards in the brewer.
(B) Remove the strainer/fl ow control and check for obstructions.
Clear or replace.
Page 11
37235 080204
TROUBLESHOOTING (cont.)
PROBLEM
Spitting or excessive steaming
Drip-out time too long
Dripping from sprayhead
PROBABLE CAUSE
1. Lime Build-up
CAUTION - Tank and tank components should be delimed regularly
depending on local water conditions. Excessive mineral build-up
on stainless steel surfaces can
initiate corrosive reactions resulting
in serious leaks.
2. Control Thermostat
1. Funnel Tip
1. Syphon System
REMEDY
Inspect tank assembly for excessive
lime deposits. Delime as required.
Refer to Service - Control Thermostat for testing procedures. See
page 17
The brew funnel should be cleaned
thoroughly before each brew cycle
to lessen the chance of tea leaf particles clogging the drip-out tip.
The brewer must be level or slightly
lower in front to syphon properly.
Water flows into tank continuously (ON/OFF Switch "ON") or
(UNSWEET/OFF/SWEET Switch in
"UNSWEET" or "SWEET" position)
Water flows into tank continuously (ON/OFF Switch "OFF") or
(UNSWEET/OFF/SWEET Switch in
"OFF" position)
2. Lime Build-up
CAUTION - Tank and tank components should be delimed regularly
depending on local water conditions. Excessive mineral build-up
on stainless steel surfaces can
initiate corrosive reactions resulting
in serious leaks.
3. Brew Solenoid Valve
1. Brew Timer
1. Brew Solenoid Valve
Inspect the tank assembly for excessive lime deposits. Delime as
required.
Refer to Service - Brew Solenoid
Valve for testing procedures. See
page 16
Refer to Service - Brew Timer for
testing procedures. See page 18
Refer to Service - Brew Solenoid
Valve for testing procedures. See
page 16
Page 12
37235 050205
TROUBLESHOOTING (cont.)
PROBLEM
Beverage overfl ows dispenser
PROBABLE CAUSE
1. Dispenser
2. Brew Timer
3. Brew Solenoid Valve
4. Dilution Timer
5. Dilution Solenoid Valve
REMEDY
The dispenser must be completely empty before starting a brew
cycle.
Refer to Service - Brew Timer for
testing procedures. See page 18
Remove the Brew Solenoid Valve
and clean any obstruction. Rebuild
or replace the valve if necessary.
See page 16
Refer to Service - Dilution Timer for
testing procedures. See page 21
Refer to Service - Dilution Solenoid
Valve for testing procedures. See
page 20
Weak beverage
1. Filter Type
2. Tea
3. Sprayhead
4. Funnel Loading
5. Water Temperature
®
BUNN
paper fi lters must be used
for proper extraction.
A suffi cient quantity of fresh, loose
tea leaves should be used for
proper extraction.
A clean stainless steel sprayhead
must be used for proper extraction.
The BUNN® paper fi lter must be
centered in the funnel and the bed
of tea leaves leveled by gentle
shaking.
Place an empty funnel on an empty
dispenser beneath the sprayhead.
Initiate a brew cycle and check the
water temperature immediately
below the sprayhead with a thermometer. The reading should not
be less than 200°F (93°C). Adjust
the control thermostat to increase
the water temperature. Replace if
necessary.
Page 13
37235 080204
TROUBLESHOOTING (cont.)
PROBLEM
Dry tea leaves remain in the funnel
Brewer is making unusual noises
PROBABLE CAUSE
1. Funnel Loading
1. Solenoid(s)
2. Plumbing Lines
3. Water Supply
REMEDY
®
The BUNN
paper fi lter must be
centered in the funnel and the bed
of grounds leveled by gently shaking.
The nut on the solenoid(s) must
be tight or it will vibrate during
operation.
Plumbing lines should not be resting on the counter top.
(A) The brewer must be connected
to a cold water line.
(B) Water pressure to the brewer
must not exceed 90 psi (620 kPa).
Install a regulator if necessary to
lower the working pressure to approximately 50 psi (345 kPa).
Sweetener is not working
4. Tank Heater
1. Sweetener box is empty
2. Flow Adjustment screw is
closed
3. Solenoid is defective
4. The Pump is defective
Remove and clean lime off the tank
heater. See page 27
Check the Sweetener box to make
sure it is not out of product.
Check the Flow Adjustment screw
to make sure the valve has not
closed.
Refer to Service -Sweetener Solenoid Valve for testing procedures.
See page 26
Check the manufacturers warranty
for additional information on testing and replacement of a defective
pump.
Page 14
37235 111904
SERVICE
This section provides procedures for testing and
replacing various major components used in this
brewer should service become necessary. Refer to
Troubleshooting for assistance in determining the
cause of any problem.
WARNING - Inspection, testing, and repair of electrical equipment should be performed only by qualifi ed
service personnel. The brewer should be disconnected
from the power source when servicing, except when
electrical tests are required and the test procedure
specifi cally states to plug in the brewer.
COMPONENT ACCESS
WARNING - Disconnect the brewer 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 top cover and rear inspection panel.
The top cover is attached with one #6-32 screw.
Removal of the top cover will allow access to ON/OFF
switch, start switch, brew timer, dilution timer, control
thermostat, limit thermostat and tank heater,
The rear inspection panel is attached with six #8-32
screws. Removal of the rear panel will allow access to
the brew solenoid valve, dilution solenoid valve and
the sweetener solenoid valve (optional), .195 GPM &
.750 GPM fl ow control and check valves.
Contents
Brew Solenoid Valve ............................................16
Control Thermostat ..............................................17
Digital Brew Timer................................................18
Dilution Timer ......................................................20
Dilution Solenoid Valve ........................................21
Limit Thermostat ..................................................22
Start Switch ....................................................... 23
ON/OFF Switch .....................................................24
UNSWEET/OFF/SWEET Switch .............................25
Sweetner Solenoid ...............................................26
Tank Heater ......................................................... 27
Wiring Diagrams ................................................. 28
Page 15
SERVICE (cont.)
BREW SOLENOID VALVE
Page 16
SERVICE (cont.)
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35
5
CONTROL THERMOSTAT
thermostat is turned fully clockwise. Connect the
brewer to the power source. The indication must
be:
a) 120 volts ac for two wire 120 volt models.
b) 230 volts ac for two wire 230 volt models.
c) 100 volts ac for two wire 100 volt models.
8. Disconnect the brewer from the power source.
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P3040
FIG. 4 CONTROL THERMOSTAT
Location:
The control thermostat is located inside hood on
the right side just behind the dilution timer.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Locate the blue/black wire on the control thermostat.
3. With a voltmeter, check the voltage across the
blue/black wire on the control thermostat and
the white wire on the tank heater for 100 volt and
120 volt two wire models or red wire on the tank
heater for 230 volt two wire models. Connect the
brewer to the power source. The indication must
be:
a) 120 volts ac for two wire 120 volt models.
b) 230 volts ac for two wire 230 volt models.
c) 100 volts ac for two wire 100 volt models.
4. Disconnect the brewer from the power source.
If voltage is present as described, reinstall the capillary
tube into the tank to the line 4.5" above the bulb, the
control thermostat is operating properly.
If voltage is not present as described, replace the
thermostat.
Removal and Replacement:
1. Remove both wires from the control thermostat
terminals.
2. Remove the thermostat capillary bulb by fi rmly
pulling up on the capillary tube at the tank lid. This
will disengage the grommet from the tank lid.
3. Remove the #8-32 screw holding the control
thermostat to its bracket.
4. Slide the grommet to the line 4.5" above the bulb
on the new capillary tube.
5. Insert the capillary bulb through the hole in the
tank lid and press the grommet fi rmly and evenly
so that the groove in the grommet fi ts into the tank
lid.
6. Carefully bend the capillary tube so that the tube
and bulb inside the tank are in a vertical position.
NOTE – The capillary tube must be clear of any electrical termination and not kinked.
7. Fasten the new control thermostat to its bracket.
8. Refer to Fig. 5 when reconnecting the wires.
9. Adjust the control thermostat as required.
If voltage is present as described, proceed to #5.
If voltage is not present as described, refer to the Wir-
ing Diagrams and check the brewer wiring harness.
5. Locate the black wire on the control thermostat.
6. Gently remove the capillary bulb and grommet
from the tank.
7. With a voltmeter, check the voltage across the
black wire of the control thermostat and the white
wire on the tank heater for 100 volt and 120 volt
two wire models or red wire on the tank heater
for 230 volt two wire models when the control
Page 17
BLK to Tank
Heater
BLU/BLK to Limit Thermostat
P1280
FIG. 5 CONTROL THERMOSTAT TERMINALS
37235 080204
SERVICE (cont.)
DIGITAL BREW TIMER
Page 18
SERVICE (cont.)
DIGITAL BREW TIMER (cont.)
To increase a brew volume, place the ON/OFF
switch in the "ON" position, press and hold the START
switch until three clicks are heard. Release the switch
and press it again one or more times. (Failure to release the switch within two seconds after the third click
causes the volume setting to be aborted and previous
volume setting will remain in memory.) Each time the
switch is pressed, two seconds are added to the brew
time period. Allow the brew cycle to fi nish in order to
verify that the desired volume has been achieved.
To decrease a brew volume, place the ON/OFF
switch in the "ON" position, press and release the
START switch once for every two-second interval to
be removed from the total brew time period; then immediately press and hold down the START switch until
three clicks are heard. Release the switch. (Failure to
release the switch within two seconds after the third
click causes the volume setting to be aborted and
previous volume setting will remain in memory). Allow the brew cycle to fi nish in order to verify that the
desired volume has been achieved.
3. Setting programming disable feature. If it be-
comes necessary to prevent anyone from changing
brew time once programmed, you can set the SET/
LOCK switch to the "LOCK" position. This will prevent
any further programming until switch is once again
put into the "SET" position.
2. Setting brew volumes. To set a brew volume,
fi rst check that the SET/LOCK switch is in the "SET"
position on the circuit board. Place the ON/OFF switch
in the "ON" position, press and hold the START switch
until three distinct clicks are heard and then release
the switch. (Failure to release the switch within two
seconds after the third click causes the volume setting
to be aborted and previous volume setting will remain
in memory.)
View the level of the liquid being dispensed. When
the desired level is reached, turn the ON/OFF switch
to "OFF".
NOTE: Several ounces of water will continue to syphon from the tank after turning the switch "OFF".
The brewer remembers this volume and will continue
to brew batches of this size until the volume setting
procedure is repeated.
NOTE: When brewing tea, volume will decrease due
to absorption by the tea grounds.
TL1 - WHI/VIO to Dilution Timer and
WHI/VIO to ON/OFF Switch
TL2 - WHI to Power Cord (100V & 120V) or
RED to Power connector (230V) and
WHI to Dilution Timer (100V & 120V) or
RED to Dilution Timer (230V)
TL3 - WHI/ORN to Start Switch
TL4 - WHI/GRN to Brew Solenoid
TL5 - WHI/YEL to Start Switch
P2037
FIG. 7 DIGITAL TIMER WIRING
Page 19
37235 080204
SERVICE (cont.)
DILUTION SOLENOID VALVE
Page 20
SERVICE (cont.)
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5
DILUTION TIMER
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FIG. 10 DILUTION TIMER
P3040
Location:
The dilution timer is located inside the hood on the
right side. It consists of the dial plate with two dials
and circuit board.
Test Procedure:
1. Disconnect the brewer from the power source and
remove the wires from terminals TL3, TL4, & TL5
of the timer and rotate both dials fully counterclockwise.
2. With a voltmeter, check the voltage across terminals TL1 and TL2 when the ON/OFF switch is in the
"ON" position. Connect the brewer to the power
source. The indication must be:
a) 120 volts ac for two wire 120 volt models.
b) 230 volts ac for two wire 230 volt models.
c) 100 volts ac for two wire 100 volt models.
3. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #4.
If voltage is not present as described, refer to the Wir-
ing Diagrams and check the wiring harness.
If continuity is present as described, reconnect the
wires to terminals TL3, TL4, & TL5 of the timer board
and proceed to #5.
If continuity is not present as described, refer to the
Wiring Diagrams and check the wiring harness.
5. With a voltmeter, check the voltage across terminals TL1 and TL4 when the ON/OFF switch is in the
"ON" position and the start switch is momentarily
placed in the lower position. Connect the brewer to
the power source. After a delay of approximately
three minutes, the indication must be:
a) 120 volts ac for two wire 120 volt models for
approximately one minute and then return to its
previous indication.
b) 230 volts ac for two wire 230 volt models for
approximately one minute and then return to its
previous indication.
c) 100 volts ac for two wire 100 volt models for
approximately one minute and then return to its
previous indication.
6. Disconnect the brewer from the power source.
If voltage is present as described, the timer is operating properly. Adjust the timer dials as required.
If voltage is not present as described, replace the
timer.
Removal and Replacement:
1. Remove all wires from the timer.
2. Remove the circuit board and dial plate from the
brackets.
4. Install the new dial plate and circuit board to the
brackets.
5. Refer to Fig. 11 when reconnecting the wires.
6. Adjust the timer dials as required.
WHI/BLU to Dilution Solenoid
RED/BLK to Start Switch
WHI to Brew Timer (100V &
120V Models)
RED to Brew Timer (230V
Models)
WHI/VIO to ON/OFF Switch
GRN to Start Switch
4. Check for continuity across the green and red/
black wires when the start switch is held in the
lower position.
Page 21
FIG. 11 DILUTION TIMER TERMINALS
P1281
37235 080204
SERVICE (cont.)
LIMIT THERMOSTAT
Page 22
Page 23
Page 24
Page 25
SERVICE (cont.)
SWEETNER SOLENOID VALVE
P3298
FIG. 20 SWEETNER SOLENOID VALVE
Location:
Viewing the brewer from the front, the sweetener
solenoid is mounted on the right side of the solenoid
mounting bracket which is secured to the bottom base
housing.
If continuity is not present as described, replace the
solenoid valve.
5. Check the solenoid valve for coil action. Connect the brewer to the power source, place the
UNSWEET/OFF/SWEET switch in the “SWEET”
position and momentarily place the start switch
in the lower position and release. At the start of
a brew cycle, listen carefully in the vicinity of the
solenoid valve for a “clicking” sound as the coil
magnet attracts and at the end of the brew cycle
when the plunger is released.
6. Disconnect the brewer from the power source.
If the sound is heard as described and sweetener
will not pass through the solenoid valve, there may
be a blockage in the sweetener line before or after
the solenoid valve or, the solenoid valve may require
inspection for wear, and removal of particles.
If the sound is not heard as described, replace the
solenoid valve.
Test Procedure:
1. Disconnect the brewer from the power source.
2. With a voltmeter, check the voltage across the
brown/white and white/violet wires on the sweetener solenoid terminals when the UNSWEET/OFF/
SWEET switch is in the “SWEET” position and the
start switch is momentarily placed in the lower
position. Connect the brewer to the power source.
After the approximate setting on the delay dial, the
indication must be:
a) 120 volts ac for two wire 120 volt models.
b) 230 volts ac for two wire 230 volt models.
c) 100 volts ac for two wire 100 volt models,
remain for the approximate setting on the dilution
dial, and then return to its previous indication.
3. Disconnect the brewer from the power supply.
If voltage is present as described, proceed to #4.
If voltage is not present as described, refer to the Wiring Diagrams and check the wiring harness.
Removal and Replacement:
1. Remove all wires from the solenoid valves.
2. Turn off the sweetener supply to the brewer.
3. Disconnect the water lines to and from the solenoid valves.
4. Remove the two #8-32 keps nuts holding the
solenoid bracket to the mounting bracket.
5. Lift out the valve and bracket.
6. Remove the two #10-32 slotted-head screws holding the solenoid valve to the mounting bracket.
7. Securely install the new solenoid valve to the
mounting bracket.
8. Attach the solenoid valve and bracket to the
mounting bracket.
9. Securely fasten the sweetener and water lines to
and from the solenoid valves.
10. Refer to Fig. 19 when reconnecting the wires.
WHI/VIO to Brew Solenoid
WHI/VIO to Brew Timer TL1
4. Remove both wires from the coil and check for
continuity across the coil terminals. If continuity
is present as described, reconnect the brown/white
and white/violet wires and proceed to #5.
Page 26
BRN/WHI to Selector
Switch
P2843
FIG. 21 SOLENOID VALVE TERMINALS
37235 050205
SERVICE (cont.)
TANK HEATER
Page 27
FIG. 23 TANK HEATER TERMINALS
P1284
SCHEMATIC WIRING DIAGRAM TB3, TB3B, TB3-LP
OPTIONAL
READY
INDICATOR
BLU
L1 N
LIMIT
THERMOSTAT
BLU/BLK
ON/OFF SWITCH
BLK
SWITCH &
THERMOSTAT
BLK
BLK BLK
"KEEP WARM" HEATER
GRN
WHI
TANK HEATER
WHI WHI
WHI
BREW
TIMER
DILUTION
TIMER
5 4 3 2 1 5 4 3 2 1
WHI/VIO WHI/VIO
WHI/VIO
WHI/VIO WHI/GRN
DILUTION
SOL
1
BREW
SOL
2
WHI
WHI/BLU
WHI/ORN
WHI/YEL
START
SWITCH
RED/BLK
GRN
100 VOLTS AC
120 VOLTS AC
2 WIRE
SINGLE PHASE
37234.0000C 05/06 © 2004 BUNN-O-MATIC CORPORATION
WHI
Page 28
37235 053006
SCHEMATIC WIRING DIAGRAM
TU3, TB3 W/SWEETENER
READY INDICATOR
BLU/BLK
SELECTOR SWITCH
UNSWEET/OFF/SWEET
BLK
120 VOLTS AC
2 WIRE
SINGLE PHASE
WHI/VIO
WHI WHI
WHI/BLU
BRN/WHI
WHI/ORN
WHI/YEL
27432.0000E 08/04 © 1996 BUNN-O-MATIC CORPORATION
WHI/BLU
Page 29
37235 050205
Page 30
Page 31
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