CEZ, CEZF,
CDBC, CDBCF
Airpot,
Thermal Carafe &
Thermal Server Brewers
DISCONTINUED VERSION
The information in this manual
is no longer current.
E
R
C
R
O
WARNINGSOU
L
ER
!
!
W
NT
PANE
E
ON
O
P
Y
M
M
N
O
A
C
P
FR
OF
O
T
L
C
A
Y
E
V
N
N
O
A
N
M
O
OF
C
RE
T
IS
N
D
B
RE
E
M
O
E
EF
C
A
PL
E
R
OPERATING & SERVICE MANUAL
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 FAX: (217) 529-6644
29253.0000F 02/04 ©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
# 00656.0000
# 00658.0000
# 10044.0000
29253 011900
Page 3
ELECTRICAL REQUIREMENTS
CAUTION - The brewer must be disconnected from the power source until specified in Initial Set-Up.
Model 15 has an attached cordset and requires 2-wire grounded service rated 120 volts ac, 15 amp, single
phase, 60 Hz.
L2 RED
WHITE
120V.A.C.
WHITE
NEUTRAL
L1 BLACK
120V.A.C.
208 or 240V.A.C.
120V.A.C.
NEUTRAL
L1 BLACK
Model 20 requires 2-wire, grounded service rated
Model 35 requires 3-wire, grounded service rated
120 volts ac, 20 amp, single phase, 60 Hz. Proceed as 120/208 or 120/240 volts ac, 20 amp, single phase, 60
follows:
Hz. 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.
1
3
NOTE - Bunn-O-Matic recommends ⁄4" copper tubing for installations of less than 25 feet and ⁄8" for more than
1
25 feet from the ⁄2" water supply line. A tight coil of copper tubing in the water line will facilitate moving the brewer
to clean the countertop. Bunn-O-Matic does not recommend the use of a saddle valve to install the brewer. The
size and shape of the hole made in the supply line by this type of device may restrict water flow.
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.
29253 091603
Page 4
OPERATING CONTROLS
Model CEZ-APS/TS/TSR
ON/OFF SWITCH
Placing the "ON/OFF" switch in the "ON" upper position enables the
brew circuit, and energizes the tank refill circuit. Placing the switch
in the "OFF" lower position stops tank refilling and brewing. Stop-
ping a brew cycle after it has been started will not stop the flow of
water into the server 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.
P1910
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.
READY INDICATOR
This indicator glows when the preselected brew water temperature has been achieved.
Model CDBC-APS/TC/TS/TSR
ON/OFF SWITCH
Pressing the "ON/OFF" switch (indicator glowing) enables the brew
circuitandenergizesthetankrefillcircuit. Pressingtheswitchagain
(indicator not glowing) stops tank refilling and brewing. Stopping a
brewcycleafterithasbeenstartedwillnotstoptheflowofwaterinto
the server until the funnel is empty.
NOTE – Hot water will be available at the faucet in a limited amount
whenthe"ON/OFF"indicatorisnotglowingbecausethetankwillnot
refill.
P1911
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.
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.
29253 111103
Page 5
INITIAL SET-UP
1. Insert an empty funnel into the funnel rails.
2. Place an empty server under the funnel.
3. Connect the brewer to the power source.
4. Model CDBC-APS/TC/TS/TSR – Press the "ON/OFF" switch (indicator glowing).
Model CEZ-APS/TS/TSR – 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 the tank refilling.
8. Model CDBC-APS/TC/TS/TSR – Press the "ON/OFF" switch (indicator glowing) then momentarily press and
release the "BREW" switch.
Model CEZ-APS/TS/TSR – Place the "ON/OFF" switch in the "ON" upper position then momentarily press and
release the "BREW" switch.
9. Allow the cycle to finish and measure the amount of water in the server. It should be 64 ounces 2. Refer
to the adjustments section of this manual should the volume need to be increased or decreased.
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 server beneath the funnel.
5. Model CDBC-APS/TC/TS/TSR – Press the "ON/OFF" switch (indicator glowing) then momentarily press and
release the "BREW" switch.
Model CEZ-APS/TC/TS/TSR – 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.
29253 111103
Page 6
CEZ-APS/TS/TSR ADJUSTMENTS & OPTIONAL SETTINGS
IMPORTANT: The tank must be full and fill so-
lenoid shut off prior to making these adjust-
ments.
Adjusting Brew Volumes
Thebrewerisfactorysettodeliver64ounces
2 for each brew cycle.
BREWVOLUMESET-UP:Usethefollowingsteps
whenthesettingisunknownoradifferentcircuit
board is being installed.
1. Place an empty funnel in the funnel rails and
an empty server or graduated vessel be-
neath the funnel.
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-off
three times (approximately 5 seconds). Re-
lease the button.
P1864
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 server 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 (approximately 5 sec-
onds), then release the "BREW" switch. Momen-
tarily 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.
P1865
To decrease the amount of water for each
brew cycle place an empty funnel in the funnel
rails and an empty server or graduated vessel
beneath the funnel. Place the "ON/OFF" switch
in the "ON", upper position. 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 5 sec-
onds), then release the "BREW" switch and al-
low the cycle to finish.
29253 071599
Page 7
CDBC-APS/TC/TS/TSR ADJUSTMENTS & OPTIONAL SETTINGS
P1912
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
willglow. Releasebothswitches. Pressingandreleasingthe"ON/OFF"switchwilltogglebetweenturningtheentire
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.
IMPORTANT: The tank must be full and fill solenoid shut off prior to making these adjustments.
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 server or graduated vessel beneath the funnel.
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-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
server 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
server 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.
29253 111103
Page 8
CDBC-APS/TC/TS/TSR ADJUSTMENTS & OPTIONAL SETTINGS (cont)
Water Sensing Threshold Adjustment Procedure
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.
Pulse Brew Setup Procedure
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.
29253 111103
Page 9
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-APS/TC/TS/TSR)
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-APS/TS/TSR)
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-APS/TC/TS/TSR & CEZ-APS/TS/TSR)
Make sure before servicing brewer that voltage is present at control board.
On CDBC-APS/TC/TS/TSR models, observe if indicator light is 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-APS/TS/TSR 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.
29253 091603
Page 10
TROUBLESHOOTING (cont.)
REFILL CIRCUIT
PROBLEM
PROBABLE CAUSE
REMEDY
Will not fill or refill
1. Power off to brewer (CDBC-APS/ Press ON/OFF switch on control
TC/TS/TSR & CEZ-APS/TS/TSR) panel to determine if power is ON.
2. Water shut off (CDBC-APS/TC/ Make sure water is ON.
TS/TSR & CEZ-APS/TS/TSR)
3. Display flashing (CDBC-APS/TC/ Brewer has shut down due to
TS/TSR) or ready light flashing malfunction (See Diagnostic Chart
(CEZ-APS/TS/TSR)
inmanual, Page19, orundertoplid
of brewer).
4. ON/OFF Switch (CDBC-APS/TC/ Make sure ON/OFF Switch is "ON"
TS/TSR & CEZ-APS/TS/TSR) and indicator is lit.
5. Lime build up on Probe (CDBC- Remove the Probe and check for
APS/TC/TS/TSR & CEZ-APS/TS/
TSR)
lime deposit on tip. Clean and
reinstall.
Disconnect the brewer from the
6. Refill Valve or Control Board power source and remove wires
(CDBC-APS/TC/TS/TSR & CEZ- fromrefillvalvecoil. Checkforcon-
APS/TS/TSR)
tinuity across the terminals of the
solenoid coil. If continuity is not
present,replacetherefillvalve(See
page 30). If continuity is present,
thevalvemaybestuckclosed.Shut
water off to brewer. Set the ON/OFF
switch to the "OFF" position. Open
the faucet and drain water down in
thetankuntilflowstopsorslowsto
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
diagramsandcheckthewiringhar-
ness.
Reset the Water Sensing Thresh-
7.Wateristooconductiveforproper oldAdjustmentProceduresonpage
operation when using the factory 9.
settingofsensingthreshold.(CDBC-
APS/TC/TS/TSR)
Fill or refill does not shut "OFF"
(ON/OFF Switch "ON")
Remove Probe and check for lime
deposits on tip. Clean and reinstall.
1. Lime build up on probe (CDBC-
APS/TC/TS/TSR & CEZ-APS/TS/
TSR)
29253 111103
Page 11
TROUBLESHOOTING (cont.)
REFILL CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Fill or refill does not shut "OFF" (ON/ 2a. Water Level Probe Sensing A) Disconnect the brewer from the
OFF Switch "ON") (cont)
System (CDBC-APS/TS/TSR)
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
upaboutaninchfromthegrommet.
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 proceed to step 3.
2b.WaterLevelProbeSensingSys- B) Disconnect the brewer from the
tem (CEZ-APS/TC/TS/TSR)
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-APS/TC/TS/TSR & CEZ- cator lamp should be lit). If water
APS/TS/TSR)
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
replacetherefillsolenoid.(Seepage
30)
4.Wateristooconductiveforproper Reset the Water Sensing Threshold
operation when using the factory Adjustment Procedures on page 9.
settingofsensingthreshold.(CDBC-
APS/TC/TS/TSR)
Fill or refill does not shut "OFF" (ON/ 1. Refill valve or control board If water continuously flows out of
OFF Switch "OFF") (CDBC-APS/TC/TS/TSR & CEZ- airventtube,disconnectthebrewer
APS/TS/TSR)
from the power source. If water
flowdoesnotstop,repairorreplace
therefillsolenoid.Ifthevalvecloses
when power is removed, replace
the control board. (See pages 21 &
22)
29253 111103
Page 12
TROUBLESHOOTING (cont.)
HEATING CIRCUIT
PROBLEM
PROBABLE CAUSE
REMEDY
Water does not heat to proper
temperature
Brewer has shut down due to
malfunction (See Diagnostic Chart
in manual, Page 19, or under top
lid).
1. Display flashing (CDBC-APS/TC/
TS/TSR) or ready light flashing
(CEZ-APS/TS/TSR)
IMPORTANT: Make sure no tem-
perature tests are taken before the
ready light is "ON". Tank tempera-
ture must be stabilized before read-
ings are taken.
Remove probe and grommet. Look
into hole on tank lid. Water must be
within one inch from top of tank.
2. Water not touching temperature
probe
A) Disconnect the brewer from the
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 proceed to step
4a.
3a. Dry Plug In Probe Sensing Sys-
tem (CDBC-APS/TC/TS/TSR)
B) Disconnect the brewer from the
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 4 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 proceed to step
4b.
3b. Dry Plug In Probe Sensing Sys-
tem (CEZ-APS/TS/TSR)
29253 111103
Page 13
TROUBLESHOOTING (cont.)
HEATING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Water does not heat to proper 4a.TemperatureProbe(CDBC-APS/ A)Removetheprobefromthegrom-
temperature (cont.)
TC/TS/TSR)
met and submerge in a water bath
of approximately 70°F(21°C). Con-
nectanohmmetertopins3and4of
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, and at
80°F(27°C) the reading should be
9.3k 2k OHMS. If the probe is
withintheseparameters, 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-
ture must be stabilized before read-
ings are taken.
4b. Temperature Probe (CEZ-APS/
TS/TSR)
B)Removetheprobefromthegrom-
met and submerge in a water bath
of approximately 70°F(21°C). Con-
nectanohmmetertopins2and3of
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, and at
80°F(27°C) the reading should be
9.3k 2k OHMS. If the probe is
withintheseparameters, reconnect
the J5 plug to the control board.
5. Limit Thermostat (CDBC-APS/ Disconnect the brewer from the
TC/TS/TSR & CEZ-APS/TS/TSR)
power source. Check for continuity
across the limit thermostat termi-
nals. Continuity should be present.
If not replace the limit thermostat.
(See page 27)
6. Tank Heater (CDBC-APS/TC/TS/ Disconnect the brewer from the
TSR & CEZ-APS/TS/TSR)
power source. Check for continuity
between the white terminal of the
terminalblockandtheblackwireon
therelayonthecontrolboard.There
should be a low OHM reading. If no
continuity is present, check for a
wiring problem, then replace the
tank heater if no wiring problem is
found. (See page 28)
Spitting or excessive steaming
1. Lime build up on temperature Inspect probe and tank assembly
probe, tank or tank heater
for excessive lime deposits. Delime
as required.
29253 111103
Page 14
TROUBLESHOOTING (cont.)
HEATING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Spitting or excessive steaming 2a.TemperatureProbe(CDBC-APS/ A)Removetheprobefromthegrom-
(cont.)
TC/TS/TSR)
met and submerge in a water bath
of approximately 70°F(21°C). Con-
nectanohmmetertopins3and4of
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, and at
80°F(27°C) the reading should be
9.3k 2k OHMS. If the probe is
withintheseparameters, reconnect
the J3 plug to the control board.
2b. Temperature Probe (CEZ-APS/ B)Removetheprobefromthegrom-
TS/TSR)
met and submerge in a water bath
of approximately 70°F(21°C). Con-
nectanohmmetertopins2and3of
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, and at
80°F(27°C) the reading should be
9.3k 2k OHMS. If the probe is
withintheseparameters, reconnect
the J5 plug to the control board.
3. Control Board (CDBC & CEZ)
Setthetemperatureto200°F(95°C).
Let tank temperature stabilize. If
temperature in tank is above tem-
perature setting by more than 7°F,
replace the control board.(See
pages 21 & 22)
1. Plumbing lines
2. Water supply
3. Lime build up
Plumbing lines should not rest on
the counter top.
Brewer is making unusual noises
The brewer must be connected to a
cold water supply.
Remove the tank lid and clean in-
sideoftankwithadelimingagent, if
necessary.
29253 111103
Page 15
TROUBLESHOOTING (cont.)
BREWING CIRCUIT
PROBLEM
PROBABLE CAUSE
REMEDY
Brew cycle will not start
1. Display flashing (CDBC-APS/TC/ Brewer has shut down due to
TS/TSR) or ready light flashing malfunction (See Diagnostic Chart
(CEZ-APS/TS/TSR)
in manual, Page 19, or under top lid
of brewer).
2. No water
Waterlinesandvalvestothebrewer
must be open.
3. No power or incorrect voltage to Check for voltage across the black
the brewer
and white terminals at the terminal
block.
4. ON/OFF switch not in the "ON" The indicator lamp must be lit
position
5. Low water temperature (Brew Allow brewer to heat until ready
lockout is enabled)
lamp is lit, or disable the brew lock-
out feature. (See page 7 or 8)
6. Water not touching refill probe Press ON/OFF switch (indicator
inside tank
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. Switchpanel(CDBC-APS/TC/TS/ Disconnect the brewer from the
TSR)
power source. Disconnect the rib-
bon connector from the control
board.Checkforcontinuitybetween
pins1&2(Anarrowontheconnec-
tor indicates pin 1). No continuity
should be present. Press the BREW
switch.Continuityshouldbepresent
for as long as the switch is held
"ON". If no continuity is present,
replace the switch membrane
decal.(See page 23)
29253 111103
Page 16
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Brew cycle will not start (cont.)
8. Control board or dispense valve If the start switch (CEZ-APS/TS/
(CDBC-APS/TC/TS/TSR & CEZ- TSR) or switch panel (CDBC-APS/
APS/TS/TSR)
TC/TS/TSR) is operating properly,
proceed as follows. Attach a volt-
meter to the terminals of the dis-
pense valve solenoid. Connect the
brewer to the power source. Turn
on the brewer and press the BREW
switch. Voltage should be present
at the solenoid terminals. If voltage
is not present, refer to the wiring
diagrams and check the wiring har-
ness.Ifvoltageispresent,checkfor
continuity across the terminals of
the solenoid coil. If continuity is not
present, replace the solenoid valve
(See page 26). If continuity is
present, the valve may be stuck
closed.
Consistently low beverage level in
thedispenserorbeverageoverflows
dispenser
1.Brewvolume(CDBC-APS/TC/TS/ Set up brewer according to instruc-
TSR & CEZ-APS/TS/TSR)
NOTE: All volumes to run with
sprayhead attached.
tionsinsection Adjustments-Brew
Volumes. (See pages 7 or 8) Using
a stop watch or second hand, time
thelengthofthebrewcycle.Record
thistimeinsidethetoplid. Ifservice
is ever needed again, 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-
place valve if necessary. (See page
26)
29253 111103
Page 17
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
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
replace the valve if necessary.(See
page 26)
Weak beverage
1. Sprayhead
A clean stainless steel spray-head
must be used for proper extraction.
2. Water temperature
Place an empty brew funnel on an
empty server beneath the spray-
head. Initiate brew cycle and check
the water temperature immediately
below the sprayhead with a ther-
mometer. The reading must not be
less than 195°F(91°C). Adjust the
temperature setting to increase the
water temperature. Refer to Initial
Set-up instructions.
3. Filter type
BUNN® paper filters must be used
for proper extraction.
4. Coffee grind
5. Funnel loading
Afinedriporgrindmustbeusedfor
proper extraction.
The BUNN® paper filter must be
centered in the funnel and the bed
of grounds leveled by shaking gen-
tly.
29253 111103
Page 18
TROUBLESHOOTING (cont.)
BREWING CIRCUIT (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Dry coffee grounds remain in the
funnel
1. Sprayhead
Makesuresprayheadispresentand
holes are clear and unobstructed.
There should be separate streams
of water coming out of each hole in
the sprayhead.
2. Funnel loading
The BUNN® paper filter must be
centered in the funnel and the bed
of grounds leveled by shaking gen-
tly.
29253 111103
Page 19
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
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
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
29253 091603
Page 20
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.
I
-
.
.
.
I
I
I
I
CTU NG
UFA SPR
/
R
AN
I
B
M
A
I
W
L
FO
.C.
A
E
EL
OD
O
F
T
H
M
VOLTS
NG
NDI
PE
ASE MORE
R
PH
O
E
NE
B
S
U
R
F
A
C
E
S
A
R
E
H
O
T
AY
DER
UN
O
M
NTS
ATE
P
D
ERE
ER
OTH
COV
ORE
E
OR
M
ON
E
C
R
L
E
U
R
WARNINGSO
R
E
N
O
P
!
T
O
N
E
N
A
!
W
O
P
P
Y
M
O
N
C
M
O
A
V
A
Y
F
R
F
O
O
T
M
E
L
A
C
N
E
N
F
O
N
O
E
C
R
T
N
IS
E
R
D
B
R
O
M
E
EF
C
LA
P
E
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 and front access
panel.
The top cover is attached with one #4-40 screw.
The front access panel is attached with four #6-32
screws.
I
/
U
NUFACT
B
MA
SPRINGFIELD, ILLINO
I
,
.
E
FOLLOW
O
F
T
H
MODEL
VOLTS A.C.
PHASE
AMP
W
WATT
NDING
R
ONE OR MORE
ED UNDE
COVER
E
OR MORE OR
ON
Contents
Control Board - CDBC-APS/TC/TS/TSR .............22
Control Board - CEZ-APS/TS/TSR......................23
Switch Panel - CDBC-APS/TC/TS/TSR ..............24
ON/OFF Switch - CEZ-APS/TS/TSR ....................25
BREW Switch (Start) - CEZ-APS/TS/TSR...........26
Dispense Valve ..................................................27
Limit Thermostat ...............................................28
Tank Heater .......................................................29
Refill Valve.........................................................31
Wiring Diagrams............................................... 32
P1913
FIG. 1 COMPONENT ACCESS
29253 111103
Page 21
SERVICE (cont.)
CONTROL BOARD - Model CDBC-APS/TC/TS/TSR
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.
I
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.
.
.
.
O
I
I
I
I
/
U
T
N
C
R
A
P
F
U
S
N
A
A
B
M
I
I
O
F
.
.C
HE
T
L
A
E
S
E
R
F
O
D
T
S
O
O
L
A
E
N
M
VO
R
O
DI
N
E
M
H
N
P
O
P
E
E
B
Y
A
R
E
M
D
S
T
N
U
EN
T
D
E
A
R
P
E
V
R
E
O
C
H
T
O
E
R
O
M
R
O
E
N
O
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.
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.
9. Refer to CDBC-APS/TC/TS/TSR Adjustments and
Optional Settings to program the new control
board.
P1914
FIG. 2 CONTROL BOARD
Location:
The Control Board is located inside the top cover
behind the front end cap.
Test Procedures:
The test procedures for the control board will vary
depending upon the problems experienced by the
brewer. Refer to the Troubleshooting guide beginning
on page 9. The troubleshooting guide is divided into
threesections,RefillCircuit,HeatingCircuit,andBrew-
ing Circuit.
29253 111103
Page 22
SERVICE (cont.)
CONTROL BOARD - Model CEZ-APS/TS/TSR
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.
J1
M
J2
J3
J5
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.
J4
D
S
U
R
F
A
C
E
S
A
R
E
H
O
T
J6
J7
:
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. Look at the bottom side
of the control board. Pin 1 of connector J6 is
markedbyasquaresolderpadandpins2,3&4are
round.
7. Check the jumper on the brew temperature lock-
outjackfordesiredfunction(enabledordisabled).
8. Check the jumper on the temperature jack for
desired brew temperature. The factory setting
should be 200°F(95°C)
P1915
FIG. 3 CONTROL BOARD
Location:
The Control Board is located inside the trunk
behind the front access panel.
9. Install a 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.
11. Connect the 8-pin connector and the 6-pin con-
nector from the main wiring harness.
12. Connectthebluewireandblackwiretotherelayon
the control board.
Test Procedures:
The test procedures for the control board will vary
depending upon the problems experienced by the
brewer. Refer to the Troubleshooting guide beginning
on page 9. The troubleshooting guide is divided into
threesections,RefillCircuit,HeatingCircuit,andBrew-
ing Circuit.
13. Refer to CEZ-APS/TS/TSR Adjustments and Op-
tional Settings to program the new control board.
29253 091603
Page 23
SERVICE (cont.)
SWITCH PANEL - Model CDBC-APS/TC/TS/TSR
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 #4-40 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 Removeanyadhesivethatremainsontheendcap.
5. Removetheadhesivebackingfromthenewswitch
panel. Inserttheribbonconnectorthroughtheslot
intheendcapandapplytheswitchpaneltotheend
cap.
.
MANUFACTURED BY BUN
B
SPRINGFIELD, ILL
A.C.
AMP
W
MODEL
VOLTS
PHAS
E
MAY BE PEN
NTS
ATE
ORPEOF THE
COVERED UNDER ONE ORHEM
R
ONE OR MOR
6. Install the control board to the back side of the end
cap using the four #6 screws, nylon washers and
the two #4-40 screws to the end cap assembly.
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.
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.
P1916
FIG. 4 SWITCH PANEL
Location:
The Switch Panel is located in the front of the
hood.
Test Procedures:
The test procedures for the switch panel and the
control board will vary depending upon the problems
experienced by the brewer. Refer to the Troubleshoot-
ing guide beginning on page 9. The troubleshooting
guide is divided into three sections, Refill Circuit,
Heating Circuit, and Brewing Circuit.
29253 111103
Page 24
SERVICE (cont.)
ON/OFF SWITCH - Model CEZ-APS/TS/TSR
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.
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.
/
MANUFACTURED BY BUNN-I
SPRINGFIELD, ILLIN..
B
R
Removal and Replacement:
FACES ARE HOT
MODEL
VOLTS A.C.
PHASE
AMP
WIRE
WATT
HERTZ
ONE OR MOREOF THE FOLLOWING PAT
COVERED UNDE
1. Remove the wires from the switch terminals.
2. Removethehoseconnectedtothefaucet.Remove
thenutsecuringthefaucetassemblytothebrewer
and remove the faucet.
ORE OTHER
ONE OR
M
N
:
WARNING
!
3. Remove the four nuts securing the end cap to the
brewer and remove the end cap.
DISCONNECT FROM POWER SOURCE
BEFORE REMOVAL OF ANY PANEL OR
REPLACEMENT OF ANY COMPONENT!
4. Remove the switch and replace with new switch.
5. Install the front end cap and faucet assembly.
6. Refer to FIG. 6 when reconnecting the wires.
P1917
FIG. 5 ON/OFF SWITCH
Location:
The ON/OFF switch is located on the front of the
hood.
WHI to Terminal
Block (White Insert)
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.
BLK to Terminal
Block (Black Insert)
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 for two wire 120 volt models and three
wire 120/240 volt models.
WHI/RED to Control
Board (J1-8)
P1918
4. Disconnect the brewer from the power source.
FIG. 6 ON/OFF SWITCH WIRING
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.
5. With the black wire removed, remove the wire
from the lower terminal.
29253 091603
Page 25
SERVICE (cont.)
BREW SWITCH (Start) - Model CEZ-APS/TS/TSR
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.
Removal and Replacement:
1. Remove the white/yellow wire and white/orange
from the BREW switch.
2. Compress the clips inside the hood and gently
push the switch through the opening.
MANUFACTURED BY BUNNI
B
SPRINGFIELD, ILLINO.
MODEL
VOLTS A.C.
PHASE
AMP
WIRE
WAT
HERT
SURFACES ARE HOT
COVERED UNDER ONE OR MOREOF THE
ONE OR MORE
N
:
3. Push new switch into the opening and spread the
clips to hold the BREW switch in the hood.
4. Refer to FIG. 8 when reconnecting the wires.
WARNING
!
DISCONNECT FROM POWER SOURCE
BEFORE REMOVAL OF ANY PANEL OR
REPLACEMENT OF ANY COMPONENT!
P1917
FIG. 7 BREW SWITCH
WHI/YEL from
Control Board J5-1
Location:
The BREW switch is located in the center front of
the hood.
WHI/ORA from
Control Board J5-6
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.
P1851
FIG. 8 BREW SWITCH WIRING
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.
29253 091603
Page 26
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.
I
.
F
Z
U
C
T
R
I
FA
NU
A
T
M
B
SP
I
I
AM
.
FO
L
HE
T
S
A.C
DEL
T
OF
E
G
MO
OL
HA
R
O
W
V
P
SE
M
NDIN
PE
R
E
NE
O
Y
B
R
O
A
M
DE
N
TS
EN
PAT
D
U
ERE
V
ER
CO
TH
O
RE
O
M
R
E
O
ON
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 level.
P1919
FIG. 9 DISPENSE VALVE
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 valve is located inside the top cover
behind the front end cap.
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.
WHI/GRN from
Control Board
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 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
FIG. 10 DISPENSE VALVE WIRING
If the sound is not heard as described, proceed to #6.
29253 091603
Page 27
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.
4. Refer to FIG. 12 when reconnecting the wires.
I
U
T
C
R
A
P
F
S
U
N
A
M
B
L
L
O
.
F
.C
E
H
T
L
A
E
S
E
R
F
O
D
T
S
O
O
L
A
E
R
M
O
N
V
P
O
O
I
M
N
D
H
N
E
P
E
E
B
Y
A
R
E
M
D
S
T
N
U
N
TE
D
E
R
PA
E
V
R
E
O
C
H
T
O
E
R
O
M
R
O
E
N
O
BLU from Control
Board
P1920
BLK from Terminal
Block
FIG. 11 LIMIT THERMOSTAT
P1800
Location:
FIG. 12 LIMIT THERMOSTAT WIRING
The limit thermostat is located inside the front
access panel on the front side of the tank.
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.
29253 091603
Page 28
SERVICE (cont.)
TANK HEATER
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. 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.
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.
P1855
FIG. 13 TANK HEATER
Location:
The tank heater is located inside the tank and
secured to the tank bottom.
Test Procedures:
1. Disconnect the brewer from the power supply.
2. With a voltmeter, check the voltage across the
white or red wire from the terminal block and the
black wire from the control board. Connect the
brewer to the power source. The indication must
be120voltsacfortwowire120voltmodelsor240
volts ac for three wire 120/240 volt models.
3. Disconnect the brewer from the power source.
12. Disconnecttheblackwireandthewhiteorredwire
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.
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.
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.
4. Disconnecttheblackwireandthewhitewireorred
wire from the tank heater terminals.
5. Check for continuity across the tank heater termi-
nals.
16. Install new tank heater with gaskets to the bottom
of the tank and secure with two hex nuts.
29253 091603
Page 29
SERVICE (cont.)
TANK HEATER (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.
BLK to Control Board
22. Connect the pink wire to the level probe.
23. Insert the temperature probe through the grom-
met in the tank lid.
WHI or RED to Terminal
Block
24. Install the elbow fitting of the vent hose into the
grommet in the tank lid.
25. On brewers with faucet, connect the outlet water
line of the faucet to the side of the tank and secure
with clamp.
P1856
FIG. 14 TANK HEATER WIRING
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.
29. Install access panels and covers and refer to Initial
Set-up for refill and operation.
29253 091603
Page 30
SERVICE (cont.)
REFILL VALVE
If continuity is not present as described, replace the
refill valve.
J1
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.
J2
J3
J5
J4
SURFACES ARE HOT
J6
J7
:
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.
Ifthe soundis notheardas described, replacetherefill
valve.
P1915
FIG. 15 REFILL VALVE
Removal and Replacement:
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.
Location:
The refill valve is located inside the trunk on the
lower center part of the component bracket.
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.
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.
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 for two wire
120 volt models and three wire 120/240 volt
models.
7. Refer to FIG. 16 when reconnecting the wires.
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.
WHI from Terminal
Block
5. Check for continuity across the refill valve coil
terminals.
WHI/BLU from
Control Board
P1858
If continuity is present as described, reconnect the
white and white/blue wires from the circuit board.
FIG. 16 REFILL VALVE WIRING
29253 091603
Page 31
SCHEMATIC WIRING DIAGRAM CDBC-APS/TS/TSR
EARLY MODELS
L1
N
L2
GRN
LIMIT
THERMOSTAT
WHI-14 (MODELS 15 & 20)
RED-14 (MODEL 35)
TANK HEATER
BLU-14
BLK-14
BLK-14
"KEEP WARM" HEATER
BLK
WHI
WHI
WHI
BLK
COUNTER
(OPTIONAL)
GRN
REFILL
BLK
BLK
BLU-14
BLK-14
WHI
J1-1
J1-2
COM
N.O.
WHI/BLU
SOL
C
O
N
T
R
O
L
DISPENSE
WHI
WHI
WHI/GRN
SOL
WHI
BLK
J1-1
P
C
WHI/BLU
J1-5
B
O
A
R
D
WHI/GRN
J1-10
J2-1
CONTROL PANEL ASSY
BREW SW
ON/OFF SW
HIDDEN SW
J2-6
STATIC
SHIELD
120V AC 2 WIRE
120/208V AC 3 WIRE
120/240V AC 3 WIRE
SINGLE PHASE
J2-11
J3-1
PNK
GRN
WHI
BLK
LEVEL
PROBE
J3-4
t°
29253 111103
Page 32
SCHEMATIC WIRING DIAGRAM CEZ-APS/TS/TSR
GRN
AUXILIARY
OUTLET
L1
N
L2
BLK
WHI
GRN
LIMIT
THERMOSTAT
WHI-14 (MODELS 15 & 20)
TANK HEATER
BLK-14
BLK-14
"KEEP WARM" HEATER
BLU-14
RED-14 (MODEL 35)
WHI
WHI
BLK
ON/OFF SWITCH
WHI
REFILL
COUNTER (OPTIONAL)
BLK
BLK
WHI/BLU
WHI
WHI/RED
BLK
BLK
BLU-14
BLK-14
SOL
TRM-1
TRM-2
COM
DISPENSE
SOL
WHI/GRN
WHI
WHI
N.O.
WHI
J1-1
C
WHI/BLU
WHI/GRN
O
N
T
R
O
L
BLK
WHI/RED
WHI/YEL
BLK
WHI
BREW SWITCH
WHI/ORA
J1-8
J5-1
B
O
A
R
D
GRN
PNK
120V AC 2 WIRE
WHI/ORA
J5-6
120/208V AC 3 WIRE
120/240V AC 3 WIRE
SINGLE PHASE
LEVEL
PROBE
GRY
PNK
J7-1
J7-2
t°
29253 091603
Page 33
SCHEMATIC WIRING DIAGRAM
CDBC 15, 20 & 35 APS/TC/TS
LATE MODELS
L1
N
L2
GRN
LIMIT
THERMOSTAT
WHI-14 (MODELS 15 & 20)
RED-14 (MODEL 35)
TANK HEATER
BLU-14
BLK-14
BLK-14
"KEEP WARM" HEATER
WHI
WHI
WHI
BLK
COUNTER
(OPTIONAL)
REFILL
BLK
BLK
J1-1
J1-2
COM
N.O.
WHI/BLU
SOL
C
O
N
T
R
O
L
DISPENSE
BLU-14
BLK-14
WHI
WHI
WHI/GRN
SOL
WHI
BLK
J1-1
P
C
WHI/BLU
J1-5
B
O
A
R
D
WHI/GRN
J1-10
J2-1
CONTROL PANEL ASSY
BREW SW
ON/OFF SW
HIDDEN SW
J2-6
120V AC 2 WIRE
120/208V AC 3 WIRE
120/240V AC 3 WIRE
SINGLE PHASE
STATIC
SHIELD
J2-11
J3-1
PNK
GRN
WHI
BLK
LEVEL
PROBE
J3-4
J5-1
BLK
t°
29253 021604
Page 34
|