CEZ
CDBC
TWIN
:
I
DISCONTINUED VERSION
The information in this manual
is no longer current.
:
TIO
N
CIO
OPERATING & SERVICE MANUAL
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 FAX: (217) 529-6644
29319.0000D 09/03 ©1999 Bunn-O-Matic Corporation
USER NOTICES
Carefully read and follow all notices in this manual and on the equipment. All labels on the equipment should be
kept in good condition. Replace any unreadable or damaged labels.
# 00986.0000
! WARNING
DO NOT OVERLOAD CIRCUIT.
ALWAYS ELECTRICALLY GROUND
THE CHASSIS OR ADAPTOR PLUG.
DO NOT DEFORM PLUG OR CORD.
FOLLOW NATIONAL AND LOCAL
ELECTRICAL CODES.
KEEP COMBUSTIBLES AWAY.
FAILURE TO COMPLY RISKS EQUIPMENT
DAMAGE, FIRE OR SHOCK HAZARD.
READ THE ENTIRE
OPERATING MANUAL BEFORE
USING THIS PRODUCT
00986.0000E 5/98 ©1994 Bunn-O-Matic Corporation
# 00656.0000
# 00658.0000
# 12364.0000
# 10044.0000
29319 041599
Page 3
ELECTRICAL REQUIREMENTS
CAUTION - The brewer must be disconnected from the power source until specified in Initial Set-Up.
One circuit models require one 3-wire, grounded service rated 120/208
L2 RED
or 120/240 volts ac, 40 amp, single phase, 60 Hz.
120V.A.C.
WHITE
208 or 240V.A.C.
Two circuit models require two 3-wire, grounded service rated 120/208
NEUTRAL
120V.A.C.
or 120/240 volts ac, 20 amp, single phase, 60 Hz.
L1 BLACK
Proceed as follows:
Electrical Hook-Up
CAUTION – 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. Remove the front panel beneath the sprayhead.
4. Feed the 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.
Replace the front panel.
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 5 and 90 psi (34.5
1
and 620 kPa) for CDBC models and 20 and 90 psi (138 and 620 kPa) for CEZ models from a ⁄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
3
is greater than 90 psi (620 kPa) to reduce it to 50 psi (345 kPa). The water inlet fitting is ⁄8" flare. Bunn-O-Matic
does not recommend the use of a reverse-osmosis or deionized water supply to this equipment.
3
1
NOTE - Bunn-O-Matic recommends ⁄8" copper tubing from a ⁄2" or larger 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.
This equipment must be installed to comply with the Basic Plumbing Code of the
Building Officials and Code Administrators International, Inc. (BOCA)
and the Food Service Sanitation Manual of the Food and Drug Administration (FDA).
Plumbing Hook-Up
1. Flush the water line.
2. Securely attach it to the flare fitting at the rear of the brewer.
3. Turn on the water supply.
29319 091203
Page 4
OPERATING CONTROLS
Model CEZ TWIN
ON/OFF
BREW
FRONT-SIDE-REAR
ON/OFF
BREW
FRONT-SIDE-REAR
P1870
ON/OFF SWITCH
Placing the "ON/OFF" switch in the "ON" upper position supplies power to the brew station warmer, enables the
brew circuit, and energizes the tank refill circuit. Placing the switch in the "OFF" lower position stops tank refilling,
brewing and deenergizes the brew station warmer. Stopping a brew cycle after it has been started will not stop the
flow of water into the decanter until the funnel is empty.
NOTE – Hot water will be available at the faucet in a limited amount when the switch is in the "OFF" position because
the tank will not refill.
BREW SWITCH
Momentarilypressingandreleasingtheswitchstartsabrewcyclewhenthe"ON/OFF"switchisinthe"ON"upper
position.
NOTE – The "ON/OFF" switch must be in the "ON" upper position to initiate and complete a brew cycle.
ADDITIONAL WARMER SWITCHES
Placing any additional warmer switch in the "ON" upper position supplies power to the associated warmer.
READY INDICATOR
This indicator glows when the preselected brew water temperature has been achieved.
Model CDBC TWIN
P1869
ON/OFF SWITCH
Pressing the "ON/OFF" switch (indicator glowing) supplies power to the brew station warmer, enables the brew
circuit, and energizes the tank refill circuit. Pressing the switch again (indicator not glowing) stops tank refilling,
brewing and deenergizes the brew station warmer. Stopping a brew cycle after it has been started will not stop the
flow of water into the decanter until the funnel is empty.
NOTE – Hot water will be available at the faucet in a limited amount when the "ON/OFF" indicator is not glowing
because the tank will not refill.
29319 041599
Page 5
BREW SWITCH
Momentarily pressing and releasing the switch starts a brew cycle when the "ON/OFF" indicator is glowing.
NOTE – The "ON/OFF" indicator must be glowing to initiate and complete a brew cycle.
ADDITIONAL WARMER SWITCHES
Pressing any additional warmer switch so the indicator is glowing, supplies power to the associated warmer.
READY INDICATOR
This indicator glows when the preset temperature has been achieved. The word "NOT" above "READY" will glow
in all other instances.
TEMPERATURE INDICATORS (Feature disabled from the factory – refer to page 8.)
The indicator glows to communicate the brew water temperature. Two indicators will glow when the
temperature is between them.
INITIAL SET-UP
1. Insert an empty funnel into the funnel rails of one of the brew stations.
2. Place an empty decanter under the funnel.
3. Connect the brewer to the power source.
4. Model CDBC – Press the "ON/OFF" switch (indicator glowing).
Model CEZ – Place the "ON/OFF" switch in the "ON" upper position.
5. Water will flow into the tank and stop when the tank is filled to its capacity.
6. Wait approximately twenty minutes for the water in the tank to heat to the proper temperature.
7. Place a small vessel beneath the faucet and open the faucet handle. Release it when you hear water once again flowing
into the tank.
8. Model CDBC – With the "ON/OFF" switch still in the "ON" position (indicator glowing), momentarily press and release
the "BREW" switch.
Model CEZ – With the "ON/OFF" switch still in the "ON" (upper position), momentarily press and release the "BREW"
switch.
9. Allow the cycle to finish and measure the amount of water in the decanter. It should be 64 ounces ± 2. Refer to the
adjustments section of this manual should the volume need to be increased or decreased.
NOTE: Repeat steps 1 through 9 for the other brew station.
The brewer is now ready for use in accordance with the coffee brewing instructions below.
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 decanter beneath the funnel.
5. ModelCDBC–Pressthe"ON/OFF"switch(indicatorglowing), thenmomentarilypressandreleasethe"BREW"switch.
Model CEZ – Place the "ON/OFF" switch in the "ON" (upper position), then momentarily press and release the "BREW"
switch.
6. When brewing is completed, simply discard the grounds and filter.
CLEANING
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.
29319 041599
Page 6
CEZ ADJUSTMENTS & OPTIONAL SETTINGS
IMPORTANT: The tank must be full and refill solenoid shut off prior to making these adjustments.
Sprayhead must be installed while making these adjustments.
Adjusting Brew Volumes (Each Brew
TRM1
COUNTER
Station must be adjusted separately)
The brewer is factory set to deliver 64
ounces ± 2 for each brew cycle.
+
J7
READY
LED
+
BREW VOLUME SET-UP: Use the following
steps when the setting is unknown or a differ-
ent circuit board is being installed.
1. Place an empty funnel in the funnel rails
and an empty decanter or graduated ves-
sel beneath the funnel.
+
J3
J6
LOCK UNLOCK
+
+
2. Place the "ON/OFF" switch in the "ON",
upper position.
3. Press and hold the brew start button until
you hear the brew solenoid click on-and-
offthreetimes(approximately5seconds).
Release the button.
(Brew Lockout Enabled)
(Brew Lockout Disabled)
LOCK UNLOCK
LOCK UNLOCK
P1864
TEMPERATURE
4. Allow the cycle to continue until the de-
sired amount of water is dispensed and
then turn "OFF" the brewer.
Thebrewerisnowsettodispensethisamount
of water for each subsequent brew cycle.
TRM1
COUNTER
+
J7
READY
LED
To increase the amount of water for each
brew cycle place an empty funnel in the funnel
rails and an empty decanter or graduated
vessel beneath the funnel. Place the "ON/OFF"
switch in the "ON", upper position. Press and
hold the "BREW" switch until you hear the
solenoid click on-and-off three times (ap-
proximately 5 seconds), then release the
"BREW" switch. Momentarily press and re-
lease the "BREW" switch once for each ounce
(approximate) of water to be added to the
priorsettingandallowthebrewcycletofinish.
+
+
J3
J6
LOCK UNLOCK
J6
+
+
4
1
TEMPERATURE
P1865
To decrease the amount of water for each
brew cycle place an empty funnel in the fun-
nel rails and an empty decanter or graduated
vessel beneath the funnel. Place the "ON/OFF"
switch in the "ON", upper position. Momen-
tarily press and release the "BREW" switch
once for each ounce (approximate) of water
to be removed from the existing setting. Press
and hold the "BREW" switch until you hear
the solenoid click on-and-off three times (ap-
proximately 5 seconds), then release the
"BREW" switch and allow the cycle to finish.
29319 041599
TEMPERATURE
TEMPERATURE
205°
205°
(200°)
(195°)
(190°)
(200°)
(195°)
(190°)
(185°)
CAL
(185°)
CAL
Page 7
CDBC ADJUSTMENTS & OPTIONAL SETTINGS
HIDDEN
HIDDEN
SWITCH
SWITCH
P1871
NOTE: The following adjustments must be performed for each Brew Station.
Setting Brew Temperature
The brewer is factory set to brew at 200°F(95°C). To change this setting, press and hold the "HIDDEN" switch
beneath the "®". The word "TEMP" above the "ON/OFF" switch will glow to correspond with the temporary function
change of this switch. Repeatedly press and release the "ON/OFF" switch until one of the bank of temperature
indicators shows the approximate desired temperature. When two indicators are glowing, the temperature is
approximately the number between them.
Displaying Brew Temperature
The brewer is factory set with the temperature display disabled. To change this setting, press and hold the "ON/
OFF" switch and the "HIDDEN" switch beneath the "®" for five seconds, the entire bank of temperature indicators
will glow. Release both switches. Pressing and releasing the "ON/OFF" switch will toggle between turning the entire
bank of temperature indicators on-or-off, signifying the "ON" or "OFF" condition of this display. Wait for a few
seconds, the brewer will maintain this last setting.
Setting Brew Lockout
Thebrewerisfactorysetwiththebrewlockoutdisabled.Brewlockoutpreventsstartingabrewcycleiftheready
indicator is not glowing. When an attempt at brewing cannot be allowed, the word "NOT" and "LOCKOUT" flash for
three seconds to indicate the reason the brew can't begin. To change the condition of the brew lockout, press and
hold the "HIDDEN" switch beneath the "®" and momentarily press the "BREW" switch.
Adjusting Automatic Warmer Shut-Off
The brewer is factory set with this feature disabled. The automatic warmer shut-off deenergizes all warmers
after a predetermined time period after the most recent brew cycle. To change the setting, press and hold the
"BREW" switch and the "HIDDEN" switch beneath the "®" for five seconds, the entire bank of temperature indicators
will flash on-and-off. Release both switches. Pressing and releasing the "BREW" switch will select the number of
temperature indicators from none to five. When no indicators are glowing, this feature is disabled and all warmers
will be controlled only by their respective switches. When one to five indicators are glowing, it indicates the
approximate number of hours of delay before all warmers will be automatically deenergized after the most recent
brew cycle.
IMPORTANT: The tank must be full and refill solenoid shut off prior to making these adjustments.
Sprayhead must be installed while making these adjustments.
29319 030101
Page 8
Adjusting Brew Volumes
The brewer is factory set to deliver 64 ounces ± 2 for each brew cycle.
BREW VOLUME SET-UP: Use the following steps when the setting is unknown or a different circuit board is being
installed.
1. Place an empty funnel in the funnel rails and an empty decanter or graduated vessel beneath the funnel.
2. Press the "ON/OFF" switch (indicator glowing).
3. Press and hold the brew start button until you hear the brew solenoid click on-and-off three times
(approximately 10 seconds). Release the button.
4. Allow the cycle to continue until the desired amount of water is dispensed and then turn "OFF" the brewer.
The brewer is now set to dispense this amount of water for each subsequent brew cycle.
To increase the amount of water for each brew cycle place an empty funnel in the funnel rails and an empty
decanter or graduated vessel beneath the funnel. Press the "ON/OFF" switch. Press and hold the "BREW" switch
until you hear the solenoid click on-and-off three times (approximately 10 seconds), then release the "BREW"
switch. Momentarily press and release the "BREW" switch once for each ounce (approximate) of water to be added
to the prior setting and allow the brew cycle to finish.
To decrease the amount of water for each brew cycle place an empty funnel in the funnel rails and an empty
decanter or graduated vessel beneath the funnel. Press the "ON/OFF" switch. Momentarily press and release the
"BREW" switch once for each ounce (approximate) of water to be removed from the existing setting. Press and
hold the "BREW" switch until you hear the solenoid click on-and-off three times (approximately 10 seconds),
then release the "BREW" switch and allow the cycle to finish.
WATER SENSING THRESHOLD ADJUSTMENT PROCEDURE (CDBC TWIN & CDBCF TWIN)
1. Make sure the tank is full of water to be used for calibration. The water must be in contact with the refill probe.
2. Unplug the brewer from the power source, then press and hold the BREW button while power is reapplied.
3. Continue pressing the BREW button until the READY indicator begins to flash. Release the BREW button and
then press it again momentarily.
4. The new calibration is automatically completed within a few seconds. If the water is too pure for use with the
brewer, the READY indicator will flash very rapidly and the old calibration will be retained.
29319 091203
Page 9
PULSE BREW SETUP PROCEDURE (CDBC TWIN & CDBCF TWIN)
The pulse brew parameters (initial fill time, off times, and remaining on times) are entered using the following set-
by-example process.
1. First set the brew volume using the standard procedure in Brew Volume Setup.
2. Position an empty container under the sprayhead. Allow the tank to finish refilling. Make sure that the READY
lamp is on, or that the BREW LOCKOUT function is turned off.
3. PressandholdtheOFF/ONbutton.Thebrewvalvewillturnonafter10seconds.Releasethebutton.Thisbegins
the initial on-time setting. When the spray has continued for the desired time, momentarily press the OFF/ON
button.
4. The spray is now stopped and the off time setting has begun. Press the OFF/ON button momentarily to end
the off time.
5. Thesprayisnowonagainandtheremainingontimesettinghasbegun. PresstheOFF/ONbuttonmomentarily
at the end of the desired remaining on time.
6. The setup is now complete and the parameters are stored in memory. The spray will continue the off and on
cyclesuntilthebrewvolumeofstep1iscomplete. PressingtheOFF/ONbuttonagainwillterminatethebrewing
cycle, with the parameters stored in memory.
7. If only a preinfusion is desired, i.e. an initial on time followed by one off period, use the same procedure, but
stop after step 4 and allow the brew to finish the volume set in step 1. This will store the initial on time and off
time in memory.
Procedure for Disabling Pulse Brew or Preinfusion:
1. Position an empty container under the sprayhead. Allow the tank to finish refilling. Make sure that the READY
lamp is on, or that the BREW LOCKOUT function is turned off.
2. Press and hold the OFF/ON button. The brew valve will turn on after 10 seconds. Release the button.
3. Allow the spray to continue and press no buttons until spray stops. The pulse and preinfusion functions are
now disabled.
NOTE: When the brewer has been set up for pulse or preinfusion, the adjustment of brew volume is done the same
as always and has no effect on the pulse brew parameters. The pulsing is temporarily disabled while adjusting the
brew volume and automatically returns during normal brewing.
29319 091203
Page 10
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, andrepairofelectricalequipmentshouldbeperformedonlybyqualifiedservicepersonnel.
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.
Theuseoftwowrenchesisrecommendedwheneverplumbingfittingsaretightenedorloosened. Thiswillhelp
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 specified.
• Follow recommended service procedures.
• Replace all protective shields or safety notices.
Before troubleshooting this brewer, check for the following:
A. Control Boards (CDBC TWIN)
1. Make sure ribbon cable is properly attached to the control board (ALL PINS INSERTED INTO PLUG).
2. Makesurethereisanyloninsulatingwasherundereachscrewheadthatholdsthecontrolboardtotheplastic
front end cap. This is important for proper operation.
B. Control Boards (CEZ TWIN)
Locate J6 connector on control board. If jumper is across pins 1 & 2, board is set up to operate tea brewer or
a brewer that DOES NOT use a water level probe. If jumper is across pins 2 & 3, board is set up to operate a
coffee brewer or a brewer that uses a water level probe. Look at the bottom side of the control board. Pin 1 of
connector J6 is marked by a square solder pad on the foil side of the board and pins 2,3 & 4 are marked by a
round solder pad.
C. Control Boards (CDBC TWIN & CEZ TWIN)
Make sure before servicing brewer that voltage is present at control board.
On CDBC TWIN models, press any warmer switch or observe if any indicator lights are glowing on the control
panel. If so, proceed with testing. If not, check for voltage across pins 1 & 2 of the ten pin J1 connector (black
and white wires). If voltage is present, replace the control board. If voltage is not present, check wiring and
voltage across terminal block (black and white). Correct the problem and retest before proceeding with testing.
On CEZ TWIN models, check for voltage across pins 1 & 7 of the eight pin J1 connector (black and white wires).
If voltage is present, proceed with testing. If voltage is not present, check wiring and voltage across terminal
block (black and white). Correct the problem and retest before proceeding with testing.
29319 091203
Page 11
TROUBLESHOOTING (cont.)
REFILL CIRCUIT
PROBLEM
PROBABLE CAUSE
REMEDY
1. Power off to brewer (CDBC &
CEZ)
Will not fill or refill
Press warmer switches on control
panel to determine if power is ON.
2. Water shut off (CDBC & CEZ)
Make sure water is ON.
3. Display flashing (CDBC) or
ready light flashing (CEZ)
Brewer has shut down due to mal-
function (See Diagnostic Chart in
manual, Page 20, or under top lid of
brewer).
4. ON/OFF Switch (CDBC & CEZ)
Make sure ON/OFF Switch is "ON"
and indicator is lit.
5. Lime build up on Probe (CDBC &
CEZ)
Remove the Probe and check for
lime deposit on tip. Clean and rein-
stall.
6. Refill Valve or Control Board
(CDBC & CEZ)
Disconnect the brewer from the
power source and remove wires
from refill valve coil. Check for con-
tinuity across the terminals of the
solenoid coil. If continuity is not
present, replace the refill valve (See
page 31). If continuity is present,
the coil may be stuck closed. Shut
water off to brewer. Set the ON/OFF
switch to the "OFF" position. Open
the faucet and drain water down in
the tank until flow stops or slows to
a trickle. Attach a voltmeter to the
terminalsoftherefillsolenoid.Con-
nectthebrewertothepowersource.
Press the switch "ON". Within five
seconds, voltageshouldbepresent
at the solenoid terminals. If voltage
is not present, refer to the wiring
diagrams and check the wiring har-
ness.
7.Wateristooconductiveforproper
operation when using the factory
settingofsensingthreshold.(CDBC)
Reset the Water Sensing Threshold
Adjustment Procedures on page 9.
1. Lime build up on probe (CDBC
& CEZ)
Fill or refill does not shut "OFF"
(ON/OFF Switch "ON")
Remove Probe and check for lime
deposits on tip. Clean and reinstall.
29319 091203
Page 12
TROUBLESHOOTING (cont.)
REFILL CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
2a.WaterLevelProbeSensingSys- A) Disconnect the brewer from the
tem (CDBC)
power source. Disconnect the J3
connector from the control board.
Check for continuity from the nut
on top of the level probe to pin 1 of
the plug, continuity should be
present.Pullthetemperatureprobe
up about an inch from the grom-
met. Check for continuity from the
outside surface of the temperature
probe and pin 4 of the plug, conti-
nuity should be present. Connect
the J3 plug to the control board and
proceed to step 3.
2b.WaterLevelProbeSensingSys- B) Disconnect the brewer from the
tem (CEZ)
power source. Disconnect the J5
connector from the control board.
Check for continuity from the nut
on top of the level probe to pin 5 of
the plug, continuity should be
present.Pullthetemperatureprobe
up about an inch from the grom-
met. Check for continuity from the
outside surface of the temperature
probe and pin 2 of the plug, conti-
nuity should be present. Connect
the J5 plug to the control board and
proceed to step 3.
3. Refill valve or control board Press ON/OFF switch to "ON" (Indi-
(CDBC & CEZ)
cator lamp should be lit). If water
continuously flows out of air vent
tube, disconnect the brewer from
the power source. If water flow
stops, replace the control board. If
water flow does not stop, repair or
replacetherefillsol-enoid.(Seepage
31)
4.Wateristooconductiveforproper Reset the Water Sensing Threshold
operation when using the factory Adjustment Procedures on page 9.
setting of sensing threshold.
Fill or refill does not shut "OFF"
(ON/OFF Switch "OFF")
1. Refill valve or control board If water continuously flows out of
(CDBC & CEZ)
airventtube,disconnectthebrewer
from the power source. If water
flowdoesnotstop,repairorreplace
therefillsolenoid.Ifthevalvecloses
when power is removed, replace
the control board. (See pages 22 &
23)
29319 091203
Page 13
TROUBLESHOOTING (cont.)
HEATING CIRCUIT
PROBABLE CAUSE
PROBLEM
REMEDY
Water does not heat to proper
temperature
1. Display flashing (CDBC) or
ready light flashing (CEZ)
Brewer has shut down due to
malfunction (See Diagnostic
Chart in manual, Page 20, or
under top lid).
IMPORTANT: Make sure no tem-
perature tests are taken before the
ready light is "ON". Tank tempera-
turemustbestabilizedbeforeread-
ings are taken.
2. Water not touching tempera-
ture probe
Removeprobeandgrommet.Look
into hole on tank lid. Water must
be within one inch from top of
tank.
3a. Dry Plug In Probe Sensing
System (CDBC)
A)Disconnectthebrewerfromthe
power source. Disconnect the J3
connector from the control board.
Check for continuity from the tank
mounting screw where the green
wire mounts, to pin 2 of the plug,
continuity should be present. Pull
the temperature probe up about
an inch from the grommet. Check
for continuity from the outside
surface of the temperature probe
and pin 4 of the plug, continuity
should be present. Connect the J3
plug to the control board and pro-
ceed to step 4a.
3b. Dry Plug In Probe Sensing
System (CEZ)
B)Disconnectthebrewerfromthe
power source. Disconnect the J5
connector from the control board.
Check for continuity from the tank
mounting screw where the green
wire mounts, to pin 5 of the plug,
continuity should be present. Pull
the temperature probe up about
an inch from the grommet. Check
for continuity from the outside
surface of the temperature probe
and pin 2 of the plug, continuity
should be present. Connect the J5
plug to the control board and pro-
ceed to step 4b.
29319 091203
Page 14
TROUBLESHOOTING (cont.)
HEATING CIRCUIT
PROBABLE CAUSE
PROBLEM
REMEDY
Water does not heat to proper
temperature (cont.)
4a. Temperature Probe (CDBC)
A) Remove the probe from the
grommetandsubmergeinawater
bathofapproximately70°F(21°C).
Connect an ohmmeter to pins 3
and 4 of the J3 connector. At
60°F(16°C) the reading should be
15.3k ± 2k OHMS, at 70°F(21°C)
the reading should be 11.8k ± 2k
OHMS,andat80°F(27°C)theread-
ing should be 9.3k ± 2k OHMS. If
the probe is within these param-
eters, reconnect the J3 plug to the
control board.
IMPORTANT: Make sure no tem-
perature tests are taken before the
ready light is "ON". Tank tempera-
turemustbestabilizedbeforeread-
ings are taken.
4b. Temperature Probe (CEZ)
B) Remove the probe from the
grommetandsubmergeinawater
bathofapproximately70°F(21°C).
Connect an ohmmeter to pins 2
and 3 of the J5 connector. At
60°F(16°C) the reading should be
15.3k ± 2k OHMS, at 70°F(21°C)
the reading should be 11.8k ± 2k
OHMS,andat80°F(27°C)theread-
ing should be 9.3k ± 2k OHMS. If
the probe is within these param-
eters, reconnect the J5 plug to the
control board.
5.LimitThermostat(CDBC&CEZ)
6. Tank Heater (CDBC & CEZ)
Disconnect the brewer from the
power source. Check for continu-
ity across the limit thermostat ter-
minals. Continuity should be
present. If not replace the limit
thermostat.(See page 28)
Disconnect the brewer from the
power source. Check for continu-
ity between the white terminal of
the terminal block and the black
wire on the relay on the control
board.ThereshouldbealowOHM
reading.Ifnocontinuityispresent,
check for a wiring problem, then
replacethetankheaterifnowiring
problem is found.(See page 29)
Spitting or excessive steaming
1. Lime build up on temperature
probe, tank or tank heater
Inspect probe and tank assembly
forexcessivelimedeposits.Delime
as required.
29319 091203
Page 15
TROUBLESHOOTING (cont.)
HEATING CIRCUIT
PROBABLE CAUSE
PROBLEM
REMEDY
Spitting or excessive steaming
(cont.)
2a. Temperature Probe (CDBC)
A) Remove the probe from the
grommetandsubmergeinawater
bathofapproximately70°F(21°C).
Connect an ohmmeter to pins 3
and 4 of the J3 connector. At
60°F(16°C) the reading should be
15.3k ± 2k OHMS, at 70°F(21°C)
the reading should be 11.8k ± 2k
OHMS,andat80°F(27°C)theread-
ing should be 9.3k ± 2k OHMS. If
the probe is within these param-
eters, reconnect the J3 plug to the
control board.
2b. Temperature Probe (CEZ)
B) Remove the probe from the
grommetandsubmergeinawater
bathofapproximately70°F(21°C).
Connect an ohmmeter to pins 2
and 3 of the J5 connector. At
60°F(16°C) the reading should be
15.3k ± 2k OHMS, at 70°F(21°C)
the reading should be 11.8k ± 2k
OHMS,andat80°F(27°C)theread-
ing should be 9.3k ± 2k OHMS. If
the probe is within these param-
eters, reconnect the J5 plug to the
control board.
3. Control Board (CDBC & CEZ)
Set the temperature to 200°F
(95°C). Let tank temperature sta-
bilize. If temperature in tank is
abovetemperaturesettingbymore
than 7°F, replace the control
board.(See pages 22 & 23)
Brewer is making unusual noises
1. Plumbing lines
2. Water supply
3. Lime build up
Plumbing lines should not rest on
the counter top.
The brewer must be connected to
a cold water supply.
Remove the tank lid and clean
insideoftankwithadelimingagent,
if necessary.
29319 091203
Page 16
TROUBLESHOOTING (cont.)
BREWING CIRCUIT
PROBLEM
PROBABLE CAUSE
REMEDY
Brew cycle will not start
1. Display flashing (CDBC) or
ready light flashing (CEZ)
Brewer has shut down due to mal-
function (See Diagnostic Chart in
manual, Page 20, or under top lid
of brewer).
2. No water
Water lines and valves to the
brewer must be open.
3.Nopowerorincorrectvoltageto
the brewer
Check for voltage across the black
and white terminals at the termi-
nal block.
4. ON/OFF switch not in the "ON"
position
The indicator lamp must be lit
5. Low water temperature (Brew
lockout is enabled)
Allow brewer to heat until ready
lamp is lit, or disable the brew
lockout feature. (See page 7 or 8)
6. Water not touching refill probe
inside tank
Press ON/OFF switch (indicator
must be lit). Brewer will refill until
water touches probe inside tank.
Water must be in contact with
refill probe before brew cycle will
start.
7. Switch panel (CDBC)
Disconnect the brewer from the
power source. Disconnect the rib-
bon connector from the control
board. Check for continuity be-
tween pins 1 & 2 (An arrow on the
connector indicates pin 1). No
continuityshouldbepresent.Press
the BREW switch. Continuity
should be present for as long as
the switch is held "ON". If no con-
tinuity is present, replace the
switchmembranedecal.(Seepage
24)
29319 091203
Page 17
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBABLE CAUSE
REMEDY
PROBLEM
Brew cycle will not start (cont.)
8. Control board or dispense valve
(CDBC & CEZ)
If the start switch (CEZ) or switch
panel (CDBC) is operating prop-
erly, proceed as follows. Attach a
voltmeter to the terminals of the
dispense solenoid. Connect the
brewer to the power source. Turn
onthebrewerandpresstheBREW
switch. Voltage should be present
at the solenoid terminals. If volt-
age is not present, refer to the
wiring diagrams and check the
wiring harness. If voltage is
present, check for continuity
across the terminals of the sole-
noid coil. If continuity is not
present, replace the solenoid (See
page 27). If continuity is present,
the valve may be stuck closed.
Consistently low beverage level in
the dispenser or beverage over-
flows dispenser
1. Brew volume (CDBC & CEZ)
Set up brewer according to in-
structionsinsection Adjustments-
BrewVolumes. (Seepages7or8)
Usingastopwatchorsecondhand,
time the length of the brew cycle.
Record this time inside the top lid.
Ifserviceiseverneededagain,use
the time as reference to determine
if time has changed.
2. Lime build up
3. Dispense Valve
Inspect the dispense valve and
sprayhead for excessive lime de-
posits. Delime as required.
Remove dispense valve and clear
any obstructions. Rebuild or re-
placevalveifnecessary.(Seepage
27)
29319 091203
Page 18
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBABLE CAUSE
REMEDY
PROBLEM
Dripping from sprayhead
1. Lime build up
Inspect the tank assembly for ex-
cessive lime deposits. Delime as
required.
2. Dispense valve
Remove the dispense valve and
clear any obstructions. Rebuild or
replacethevalveifnecessary.(See
page 27)
Weak beverage
1. Sprayhead
A six-hole stainless steel spray-
head must be used for proper ex-
traction.
2. Water temperature
Place an empty brew funnel on an
empty decanter beneath the
sprayhead. Initiate brew cycle and
check the water temperature im-
mediately below the sprayhead
with a thermometer. The reading
mustnotbelessthan195°F(91°C).
Adjust the temperature setting to
increase the water temperature.
RefertoInitialSet-upinstructions.
3. Filter type
BUNN® paper filters must be used
for proper extraction.
4. Coffee grind
5. Funnel loading
A fine or drip grind must be used
for proper extraction.
The BUNN® paper filter must be
centered in the funnel and the bed
ofgroundsleveledbyshakinggen-
tly.
29319 091203
Page 19
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Dry coffee grounds remain in the
funnel
1. Sprayhead
Make sure sprayhead is present
and holes are clear and unob-
structed.Thereshouldbesixsepa-
rate streams of water coming out
of the sprayhead.
2. Funnel loading
1. Warmer
The BUNN® paper filter must be
centered in the funnel and the bed
ofgroundsleveledbyshakinggen-
tly.
Low beverage serving tempera-
ture
Disconnect the brewer from the
powersource.Removethewarmer
plate and turn upside down to ex-
pose the warmer terminals. Re-
move the two wires. Check for
continuity across the two warmer
terminals. If continuity is not
present, replace the warmer ele-
ment (See page 32). If continuity
is present, reconnect the wires to
the warmer element. Check for
voltage at the warmer terminals.
Turn the warmer switch "ON". The
indicator light will come on. Volt-
age should be present at the ter-
minals. If not, disconnect power
supply and check wiring and
switch.
29319 091203
Page 20
DIAGNOSTICS
Intermittent flashing of the READY indicator (Model CEZ) or the bank of temperature indicators (Model CDBC)
indicates that a fault exists. Count the number of flashes between pauses and use this chart as a guide to
investigating the fault.
FLASHES CAUSE
THINGS TO CHECK
1
2
Dry Plug - In Fault -
Water Pressure (is water shut off?)
Sheath of temperature probe dry for 10 minutes after power-up Temperature probe wiring
Fill valve wiring, function, & strainer
Green wire between tank and circuit board
Low Tank Level Fault -
Level probe dry for 7 minutes after fill valve is energized
Water pressure (is water shut off?)
Shorting pin on J6 connector of control board not
on correct set of pins (CEZ boards only). See page 7
Level probe wiring
Temperature probe wiring
Fill valve wiring, function, & strainer
3
4
Low Water Temperature Fault -
Sensor in tank is calling for heat for 30 minutes or more
Tank heater wiring & function
Temperature probe wiring
Tank Sensor Disagreement -
Level probe detects water, but dry plug-in probe dry
Temperature probe wiring
Level probe wiring
Green wire between tank and circuit board
5
6
Temp Sensor Out-of-Range - High
Temp Sensor Out-of-Range - Low
Sensor not connected to circuit board
Sensor wires shorted together or to chassis
29319 091203
Page 21
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 electri-
cal equipment should be performed only by qualified
service personnel. The brewer should be unplugged
when servicing, except when electrical tests are re-
quired and the test procedure specifically states to
plug-in the brewer.
F
C
C
I
I
H
A
L
N-TC
N
ON
:
CION
:
COMPONENT ACCESS
WARNING - Disconnect the brewer from the power
source before the removal of any panel or the replace-
ment of any component.
All components are accessible by the removal of
the top cover or warmer housing, front access panel
and warmer plate(s).
The top cover is attached with one #4-40 screw.
C
I
.
.
.
.
.
.
CK
R
BD
HA
UH
C
R
I
I
R
A
T
:
The front access panel is attached with four #6-32
screws.
CTION
:
Each warmer assembly is attached with three #4-
40 screws.
P1872
FIG. 1 COMPONENT ACCESS
Contents
Control Board - CDBC ........................................23
Control Board - CEZ...........................................24
Switch Panel - CDBC ........................................25
ON/OFF Switches - CEZ .....................................26
BREW Switch (Start) - CEZ................................27
Dispense Valve ..................................................28
Limit Thermostat ...............................................29
Tank Heater .......................................................30
Refill Valve.........................................................32
Warmer Elements ..............................................33
Wiring Diagrams............................................... 34
29319 091203
Page 22
SERVICE (cont.)
PC CONTROL BOARD - Model CDBC
Removal and Replacement:
1. Disconnect the black wire and blue wire from the
relay on the control board.
2. Disconnect the 10-pin connector and the 4-pin
connector from the main wiring harness.
3. Disconnect the 11-pin connector from the control
panel.
4. Remove the four #6 screws and four nylon wash-
ers and the two #4-40 screws securing the control
board to the end cap assembly.
5. Install a new control board and secure with the
four #6 screws and nylon washers and the two #4-
40 screws to the end cap assembly.
I
I
I
E
I
-
U
5
5
:
TION
:
NOTE: The four nylon washers must be installed
under the heads of the four #6 screws to prevent
a possible shorting of the control board circuits.
6. Connect the 11-pin connector from the control
panel.
7. Connect the 10-pin connector and the 4-pin con-
nector from the main wiring harness.
8. Connectthebluewireandblackwiretotherelayon
the control board.
P1873
FIG. 2 CONTROL BOARDS - CDBC
Location:
The Control Boards are located inside the top
cover behind the front end caps.
9. Refer to CDBC Adjustments and Optional Settings
to program the new control board.
Test Procedures:
The test procedures for the control boards will
varydependingupontheproblemsexperiencedbythe
brewer. Refer to the Troubleshooting guide beginning
on page 10. The troubleshooting guide is divided into
threesections,RefillCircuit,HeatingCircuit,andBrew-
ing Circuit.
29319 091203
Page 23
SERVICE (cont.)
PC CONTROL BOARD - Model CEZ
Removal and Replacement:
1. Disconnect the black wire and blue wire from the
relay on the control board.
2. Disconnect the 8-pin connector and the 6-pin
connector from the main wiring harness.
3. Disconnect the 2-pin connector from the ready
indicator LED.
J
1
J2
R
J3
EA
-R
E
T-SID
ON
FR
5
T
J
R
STA
R
E
W
J
O
/L
N
O
A
N
D
S
U
R
F
A
C
E
S
A
R
E
H
O
T
J6
:
J7
J2
R
J3
EA
-R
E
ID
-S
T
4. Remove the four #6-32 screws securing the con-
trol board to the component mounting bracket.
5. Remove the four spacers from the control board
and attach them to the new board.
N
O
J5
FR
T
J4
TAR
S
R
E
W
/
S
U
R
F
A
C
E
S
A
R
E
H
O
T
J6
:
J7
I
6. Locate J6 connector on control board. If jumper is
across pins 1 & 2, board is set to operate tea
brewer or a brewer that DOES NOT use a water
level probe. If jumper is across pins 2 & 3, board
is set to operate a coffee brewer or a brewer that
uses a water level probe. Pin 1 of connector J6 is
marked by a square solder pad and pins 2, 3 & 4
are round.
:
N
I
U
A
C
P1874
FIG. 3 CONTROL BOARDS - CEZ
7. Checkthejumperonthebrewtemperaturelockout
jack for desired function (enabled or disabled).
8. Check the jumper on the temperature jack for
desired brew temperature. The factory setting
should be 200°F(95°C).
9. Install the new control board and secure with the
four #6-32 screws to the component mounting
bracket.
10. Connect the 2-pin connector from the ready indi-
cator LED to the board.
11. Connect the 8-pin connector and the 6-pin con-
nector from the main wiring harness to the board.
12. Connect the blue wire from the limit thermostat
and the BLK wire from the tank heater to the relay
on the control board.
Location:
The Control Boards are located inside the trunk
behind the front access panel.
Test Procedures:
The test procedures for the control boards will
varydependingupontheproblemsexperiencedbythe
brewer. Refer to the troubleshooting guide beginning
on page 10. The troubleshooting guide is divided into
threesections,RefillCircuit,HeatingCircuitandBrew-
ing Circuit.
13. RefertoCEZAdjustmentsandOptionalSettingsto
program the new control board.
29319 091203
Page 24
SERVICE (cont.)
SWITCH PANEL - Model CDBC
Removal and Replacement:
1. Disconnect the 11-pin connector to the switch
panel from the control board.
2. Remove the four #6 screws, nylon washers and
the two #4 screws securing the control board to
the end cap assembly and set aside.
3. Gently pry the switch panel from the end cap
assembly.
4. Remove any adhesive that remains on the end
cap.
I
I
I
I
5. Removetheadhesivebackingfromthenewswitch
panel. Insert the ribbon connector through the
slot in the end cap and apply the switch panel to
the end cap.
I
TION
:
6. Installthecontrolboardtothebacksideoftheend
cap using the four #6 screws, nylon washers and
the two #4 screws to the end cap assembly.
NOTE: The four nylon washers must be installed
under the heads of the four #6 screws to prevent
possible shorting of the control board circuits.
7. Reconnect the 11-pin connector from the switch
panel to the control board making sure every pin
on the control board is inserted into the ribbon
cable plug.
ION
:
P1875
FIG. 4 SWITCH PANELS - CDBC
Location:
The Switch Panels are located on the front of the
hood.
Test Procedures:
The test procedures for the switch panels and the
control boards will vary depending upon the problems
experienced by the brewer. Refer to the troubleshoot-
ing guide beginning on page 10. The troubleshooting
guide is divided into three sections, Refill Circuit,
Heating Circuit and Brewing Circuit.
29319 091203
Page 25
SERVICE (cont.)
ON/OFF SWITCHES - Model CEZ
If continuity is present as described, reconnect the
black wire to the center terminal and the remaining
wire to the lower terminal.
If continuity is not present as described, replace the
switch.
J
Removal and Replacement:
J
R
J3
EA
E-R
ID
-S
T
N
O
FR
J
1. If switch to be removed is in the left control panel
and brewer is equipped with a faucet, turn off
water supply and remove faucet.
T
R
TA
J
S
R
E
W
J
/LO
N
O
AND SACES ARE HOT
J6
1
J7
J2
R
J3
EA
E-R
-SD
T
ON
R
F
J
T
R
J4
TA
S
R
E
W
2. Remove front end cap
ACES ARE HOT
J6
I
3. Remove the wires from the switch terminals.
4. Compress the clips inside the hood and gently
push the switch through the opening.
J7
N
U
R
F
R
A
F
U
IL
A
8
5
6
:
N
P
5. Push the new switch into the opening and spread
the clips to hold switch in the hood.
6. Refer to FIG. 6 when reconnecting the wires.
7. Replace front end cap and faucet (if removed).
P1876
FIG. 5 ON/OFF SWITCHES
Location:
The ON/OFF switches are located on the front of
the hood.
WHI to Terminal Block (White
Insert on 120V or 120/240V
Models)
RED to Terminal Block (Red
Insert on 200V or 230V
Models)
Test Procedure:
1. Disconnect the brewer from the power source.
2. Viewingtheswitchfromthebackremovethewhite
wire from the upper terminal and the black wire
from the center terminal.
3. With a voltmeter, check the voltage across the
white wire and the black wire. Connect the brewer
to the power source. The indication must be 120
volts ac.
BLK to Terminal Block (Black
Insert)
Terminal #1 (See chart below)
P1918
4. Disconnect the brewer from the power source.
Connect wire to Terminal #1 as follows:
If voltage is present as described, reconnect the white
wire and proceed to #5.
If voltage is not present as described, refer to the
Wiring Diagrams and check the brewer wiring har-
ness.
Brew Station Warmers............................................WHI/RED
Side Warmers
(Front) .................................................................... BRN/BLK
(Rear) .............................................................................. VIO
FIG. 6 ON/OFF SWITCH WIRING
5. With the black wire removed, remove the wire
from the lower terminal.
6. Check for continuity across the center and lower
terminal with the switch in the "ON" position.
Continuity must not be present when the switch is
in the "OFF" position.
29319 091203
Page 26
SERVICE (cont.)
BREW SWITCH (Start) - Model CEZ
If continuity is present as described, reconnect the
white/yellow wire to the top terminal and the white/
orange to the bottom terminal.
If continuity is not present as described, replace the
switch.
J
J2
J3
Removal and Replacement:
J
FRONT-SIDE-REAR
J4
START
J1
ON/LOWER
1. If switch to be removed is in the left control panel
and brewer is equipped with a faucet, turn off
water supply and remove faucet.
S AND SURFACES ARE
J6
N
:
J7
J2
J5
FRONT-SIDE-REAR
J4
START
.
.
.
D SURFACES A
6
2. Remove front end cap.
T
:
FUNNEL C
RE TKJU
ARE HOT
FAILU
8
5
6
:
N
P
3. Remove the white/yellow wire and white/orange
from the BREW switch.
4. Compress the clips inside the hood and gently
push the switch through the opening.
5. Push new switch into the opening and spread the
clips to hold the BREW switch in the hood.
6. Refer to FIG. 8 when reconnecting the wires.
7. Replace front end cap and faucet (if removed).
P1849
FIG. 7 BREW SWITCHES
Location:
The BREW switches are located on the front of the
hood.
WHI/YEL from
Control Board J5-1
Test Procedure:
1. Disconnect the brewer from the power source.
2. Disconnect the white/yellow wire from the top
switch terminal and the white/orange from the
bottom switch terminal.
3. Check for continuity across the two terminals on
the switch when it is held in the lower position.
Continuity must not be present across these ter-
minals when the switch is released.
WHI/ORA from
Control Board J5-6
P1851
FIG. 8 BREW SWITCH WIRING
29319 091203
Page 27
SERVICE (cont.)
DISPENSE VALVE
6. Connect the voltmeter lead ends to the dispense
valve coil terminals. Connect the brewer to the
power source. Brewer temperature lockout must
be disabled. Place "ON/OFF" Switch in the "ON"
position. Press and release the brew switch. The
indication must be 120 volts ac for two-wire 120
volt models and three-wire 120/208 volt models.
7. Disconnect the brewer from the power source.
If voltage is present as described, but no coil action is
observed, nor "clicking" heard, dispense valve is de-
fective. Replace valve and test again to verify repair.
If voltage is not present as described, refer to Wiring
Diagrams and check the brewer wiring harness. Also
check the control board for proper operation. See
Pages 22 and 23.
A
N
Removal and Replacement:
1. Disconnect wires from the dispense valve.
2. Drain enough water from the tank so the dispense
valve is above the water line.
P1877
FIG. 9 DISPENSE VALVES
3. Remove water lines from the dispense valve.
4. Remove the two #8-32 nuts securing the dispense
valve to the sprayhead panel.
5. Install a new dispense valve using the two #8-32
nuts.
6. Reconnect water lines to the dispense valve and
secure in place with clamps.
7. Refer to FIG. 10 when reconnecting wires.
Location:
The dispense valves are located inside the top
cover, attached to the sprayhead panels.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Check the water level in the tank to confirm that it
is within 1/2" from the top of the tank.
3. Connect the brewer to the power source. If the
brewer has been set for brewer temperature lock-
out, this feature must be disabled. See Page 8 for
procedure.
4. Check the dispense valve for coil action. Place the
ON/OFF switch in the "ON" position, press and
release the BREW switch. Listen carefully in the
vicinity of the dispense valve for a "clicking" sound
as the coil magnet attracts and repels the plunger.
5. Disconnect the brewer from the power source.
WHI/GRN from PC
Control Board
WHI from Terminal
Block
If the sound is heard as described, there may be a
blockage in the dispense valve or the water line to the
sprayhead. Removethedispensevalveandinspectfor
wear, and remove waterborne particles.
P1853
If the sound is not heard as described, proceed to #6.
FIG. 10 DISPENSE VALVE WIRING
29319 091203
Page 28
SERVICE (cont.)
LIMIT THERMOSTAT
Removal and Replacement:
1. Remove the black and blue wires from limit ther-
mostat terminals.
2. Carefully slide the limit thermostat out from under
the retaining clip and remove limit thermostat.
3. Carefully slide the new limit thermostat into the
retaining clip.
J
4. Refer to FIG. 12 when reconnecting the wires.
J2
J
EAR
IDE-R
T-S
N
FRO
J
J
START
J
ER
OW
/L
ON
J6
1
:
J
J2
J
AR
E
-R
T-SIDE
N
FRO
J5
T
R
J4
TA
S
R
E
BLU from Control
Board
6
I
:
J7
EL
N
RE HO
FUN
O
E
A
ILUR
FA
8
65
:
N
P
P1878
FIG. 11 LIMIT THERMOSTATS
BLK from Terminal
Block
P1800
Location:
FIG. 12 LIMIT THERMOSTAT WIRING
The limit thermostats are located inside the front
access panel on the front side of the tanks.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the blue and black wires from the limit
thermostat.
3. Withanohmmeter,checkforcontinuityacrossthe
limit thermostat terminals.
If continuity is present as described, the limit thermo-
stat is operating properly.
If continuity is not present as described, replace the
limit thermostat.
29319 091203
Page 29
SERVICE (cont.)
TANK HEATERS
If continuity is present as described, reconnect the
wires, the tank heater is operating properly.
If continuity is not present as described, replace the
tank heater.
NOTE- If the tank heater remains unable to heat,
remove and inspect heater for cracks in the sheath.
Removal and Replacement:
1. Remove the top cover or top warmer housing and
front access panel as previously described.
2. Disconnect the vent hose from the top of the tank
by pulling the elbow fitting from the grommet in
the top of the tank lid.
3. Drain water from the tank.
4. Disconnect the water supply tube to the dispense
valve from the side of the tank.
5. Disconnect the water supply tube to the solenoid
valve from the bottom of the tank.
6. If removing the left tank, on brewers with faucet,
disconnect the outlet water line to the faucet from
the side of the tank.
7. Disconnect the temperature probe from the top of
the tank by pulling the probe from the grommet in
the top of the tank lid.
P1855
FIG. 13 TANK HEATER
Location:
The tank heaters are located inside the tanks and
secured to the tank bottoms.
8. Disconnect the pink wire from the level probe.
9. Disconnectthegreenwirefromthetopofthetank.
10. Disconnect the limit thermostat from the side of
the tank.
11. Disconnect the two white wires from the tank
warmer blanket.
12. Disconnect the black wire and red wire from the
tank heater terminals.
13. Remove the four #8-32 nuts securing the tank to
the mounting brackets and remove the tank as-
sembly.
Test Procedures:
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the voltage across the red
wire from the terminal block and the black wire
from the control board. Connect the brewer to the
power source. The indication must be 240 volts
ac.
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
Wiring Diagrams and check wiring harness.
14. Remove the eight #8-32 nuts securing the tank lid
to the tank.
15. Remove the two hex nuts securing the tank heater
to the bottom of the tank. Remove tank heater with
gaskets and discard.
16. Install new tank heater with gaskets to the bottom
of the tank and secure with two hex nuts.
4. Disconnect the black wire and the red wire from
the tank heater terminals.
5. Check for continuity across the tank heater termi-
nals.
29319 091203
Page 30
SERVICE (cont.)
TANK HEATERS (Cont.)
17. Install tank assembly onto mounting brackets and
secure in place with four #8-32 nuts.
18. Install tank lid and secure in place with eight #8-32
nuts.
19. Connect the two white wires of the tank warmer
blanket.
20. Connectthelimitthermostattothefrontofthetank
assembly.
21. Connect the green wire to the tank mounting
bracket using #8-32 nut.
22. Connect the pink wire to the level probe.
23. Insert the temperature probe through the grom-
met in the tank lid.
BLK to Control Board
RED to Terminal Block
24. Install the elbow fitting of the vent hose into the
grommet in the tank lid.
P1856
25. If installing left tank, on brewers with faucet,
connect the outlet water line of the faucet to the
side of the tank and secure with clamp.
26. Connect the water supply tube from the solenoid
to the bottom of the tank and secure with clamp.
27. Connect the water supply tube from the dispense
valvetothesideofthetankandsecurewithclamp.
28. RefertoFIG. 14whenreconnectingthetankheater
wires.
FIG. 14 TANK HEATER WIRING
29. Install access panels and covers and refer to Initial
Set-up for refill and operation.
29319 091203
Page 31
SERVICE (cont.)
REFILL VALVE
6. Check the refill valve for coil action. Connect the
brewer to the power source. With "ON/OFF" switch
in the "ON' upper position press start switch and
listen carefully in the vicinity of the refill valve for
a" clicking" sound as the coil magnet attracts.
7. Disconnect the brewer from the power source.
J
J
J3
J5
F
T
R
TA
J
S
J
ER
W
ON/LO
S AND SURFACE
J6
J7
J2
3
AR
E-RE
T-SID
RON
F
J
RT
J4
STA
R
E
SURFACES ARE HOT
J6
J
If the sound is heard as described and water will not
pass through the refill valve, there may be a blockage
in the water line before the refill valve or, the solenoid
valve may require inspection for wear, and removal of
waterborne particles.
U
Ifthe soundis notheardas described, replacetherefill
valve.
Removal and Replacement:
P1874
1. Remove both wires from the refill valve.
2. Turn off the water supply to the brewer.
3. Disconnect the water lines to and from the refill
valve.
FIG. 15 REFILL VALVE
Location:
4. Remove the two 1/4"-20 screws securing the refill
valvemountingbracket tothecomponentbracket.
Remove bracket and valve as an assembly.
5. Using two 1/4"-20 screws install the new refill
valve and bracket to the component bracket.
6. Securely fasten the water lines to and from the
valve.
The refill valves are located inside the trunk on the
lower center part of the component brackets.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the white and white/blue wires from
the refill valve. Set the "ON/OFF" switch in the "ON"
upper position.
7. Refer to FIG. 16 when reconnecting the wires.
3. With a voltmeter, check the voltage across the coil
wires. Connect the brewer to the power source.
The indication must be 120 volts ac.
4. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #5.
If voltage is not present as described, refer to Wiring
Diagrams and check brewer wiring harness.
5. Check for continuity across the refill valve coil
terminals.
WHI from Terminal
Block
If continuity is present as described, reconnect the
white and white/blue wires from the circuit board.
If continuity is not present as described, replace the
refill valve.
WHI/BLU from
Control Board
P1858
FIG. 16 REFILL VALVE WIRING
29319 091203
Page 32
SERVICE (cont.)
WARMER ELEMENT(S)
5. Check the continuity across the two terminals on
the warmer element.
Ifcontinuityispresentasdescribed,reconnectthetwo
wires to the warmer element.
If continuity is not present as described, replace the
warmer element.
C
I
A
C
H
I
I
J
Removal and Replacement:
A
T
TC
L
-
N
N
1. Remove the three #4-40 screws securing the
warmer assembly to the brewer.
ION
:
2. Lift the warmer assembly from the brewer.
3. Disconnect the two wires from the warmer ele-
ment terminals.
ON
:
4. Remove the two #8-32 nuts securing the warmer
element to the warmer plate.
5. Securely install new warmer element.
6. Reconnectthetwowirestowarmerelementtermi-
nals.
7. Securely install warmer assembly on the brewer.
8. Refer to the Wiring Diagrams when reconnecting
the wires.
P1875
FIG. 15 WARMER ELEMENTS
Location:
The warmerelementsarelocatedunderthewarmer
plates.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Use the white wire from the terminal block and the
other bottom wire on the "ON/OFF" switch.
3. With a voltmeter, check voltage across the two
wires with the "ON/OFF" switch in the "ON" posi-
tion. Connect the brewer to the power source.The
indication must be 120 volts ac.
4. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #5.
If voltage is not present as described, refer to Wiring
Diagrams and check brewer wiring harness.
29319 091203
Page 33
29319 091203
Page 34
29319 091203
Page 35
29319 091203
Page 36
|