Bunn CDBCF Airpot User Manual

CEZ, CEZF,

CDBC, CDBCF

Airpot,

Thermal Carafe &

Thermal Server Brewers

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OPERATING & SERVICE MANUAL

BUNN-O-MATIC CORPORATION

POST OFFICE BOX 3227

SPRINGFIELD, ILLINOIS 62708-3227

PHONE: [phone] FAX: [phone]

29253.0000F 02/04 ©1999 Bunn-O-Matic Corporation

www.bunnomatic.com

INTRODUCTION

This equipment will automatically brew a half-gallon batch of coffee into an awaiting server at the press of a
button. A hot water faucet may be included for allied beverage use. Most functions of the brewer are digitally
controlled. It is only for indoor use on a sturdy counter or shelf.

CONTENTS

Introduction & Warranty .................................................................................... 2

User Notices ...................................................................................................... 3

Electrical & Plumbing Requirements ................................................................. 4

Operating Controls............................................................................................. 5

Initial Set-Up, Coffee Brewing, & Cleaning......................................................... 6

CEZ-APS/TS/TSR Adjustments & Optional Settings .......................................... 7

CDBC-APS/TC/TS/TSR Adjustments & Optional Settings .................................. 8

Water Sensing Threshold Adjustment Procedure .............................................. 9

Pulse Brew Setup Procedure ............................................................................. 9

Troubleshooting ............................................................................................... 10

Service............................................................................................................. 21

Wiring Diagrams.............................................................................................. 32

BUNN-O-MATIC COMMERCIAL PRODUCT WARRANTY

Bunn-O-Matic Corp. (“BUNN”) warrants equipment manufactured by it as follows:

1) All equipment other than as specified below: 2 years parts and 1 year labor.

2) Electronic circuit and/or control boards: parts and labor for 3 years.

3) Compressors on refrigeration equipment: 5 years parts and 1 year labor.

4) Grinding burrs on coffee grinding equipment to grind coffee to meet original factory screen sieve analysis: parts and labor for 3 years
or 30,000 pounds of coffee, whichever comes first.

These warranty periods run from the date of installation BUNN warrants that the equipment manufactured by it will be commercially
free of defects in material and workmanship existing at the time of manufacture and appearing within the applicable warranty period.
This warranty does not apply to any equipment, component or part that was not manufactured by BUNN or that, in BUNN’s judgment,
has been affected by misuse, neglect, alteration, improper installation or operation, improper maintenance or repair, damage or
casualty. This warranty is conditioned on the Buyer 1) giving BUNN prompt notice of any claim to be made under this warranty by
telephone at [phone] or by writing to Post Office Box 3227, Springfield, Illinois 62708-3227; 2) if requested by BUNN, shipping
the defective equipment prepaid to an authorized BUNN service location; and 3) receiving prior authorization from BUNN that the
defective equipment is under warranty.

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

make additional warranties that are binding on BUNN. Accordingly, statements by such individuals, whether oral or written, do not
constitute warranties and should not be relied upon.

If BUNN determines in its sole discretion that the equipment does not conform to the warranty, BUNN, at its exclusive option while the
equipment is under warranty, shall either 1) provide at no charge replacement parts and/or labor (during the applicable parts and labor
warranty periods specified above) to repair the defective components, provided that this repair is done by a BUNN Authorized Service
Representative; or 2) shall replace the equipment or refund the purchase price for the equipment.

THE BUYER’S REMEDY AGAINST BUNN FOR THE BREACH OF ANY OBLIGATION ARISING OUT OF THE SALE OF THIS EQUIPMENT,
WHETHER DERIVED FROM WARRANTY OR OTHERWISE, SHALL BE LIMITED, AT BUNN’S SOLE OPTION AS SPECIFIED HEREIN, TO
REPAIR, REPLACEMENT OR REFUND.

In no event shall BUNN be liable for any other damage or loss, including, but not limited to, lost profits, lost sales, loss of use of
equipment, claims of Buyer’s customers, cost of capital, cost of down time, cost of substitute equipment, facilities or services, or any

other special, incidental or consequential damages.

BUNN, CDBC-APS, CDBCF-TS, CDBCF-TC and CDBC-TSR are either trademarks or registered trademarks of Bunn-O-Matic Corporation.

Page 2

29253 021604

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

Page 3

29253 011900

ELECTRICAL REQUIREMENTS

CAUTION - The brewer must be disconnected from the power source until specified in

Model 15 has an attached cordset and requires 2-wire grounded service rated 120 volts ac, 15 amp, single

phase, 60 Hz.

Initial Set-Up.

WHITE

NEUTRAL
L1 BLACK

120V.A.C.

Model 20 requires 2-wire, grounded service rated
120 volts ac, 20 amp, single phase, 60 Hz. Proceed as
follows:

Model 35 requires 3-wire, grounded service rated

120/208 or 120/240 volts ac, 20 amp, single phase, 60
Hz. Proceed as follows:

L2 RED

WHITE

NEUTRAL

L1 BLACK

120V.A.C.

208 or 240V.A.C.

120V.A.C.

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
and 620 kPa) for CDBC models and 20 and 90 psi (138 and 620 kPa) for CEZ models from a 1⁄2" or larger supply
line. A shut-off valve should be installed in the line before the brewer. Install a regulator in the line when pressure
is greater than 90 psi (620 kPa) to reduce it to 50 psi (345 kPa). The water inlet fitting is 3⁄8" flare. Bunn-O-Matic
does not recommend the use of a reverse-osmosis or deionized water supply to this equipment.

NOTE - Bunn-O-Matic recommends 1⁄4" copper tubing for installations of less than 25 feet and 3⁄8" for more than
25 feet from the 1⁄2" water supply line. A tight coil of copper tubing in the water line will facilitate moving the brewer
to clean the countertop. Bunn-O-Matic does not recommend the use of a saddle valve to install the brewer. The
size and shape of the hole made in the supply line by this type of device may restrict water flow.

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.

Page 4

29253 091603

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. Stop­ping 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

P1910

when the switch is in the "OFF" position because the tank will not
refill.

BREW SWITCH

Momentarily pressing and releasing the switch starts a brew cycle when the "ON/OFF" switch is in the "ON" upper

position.

NOTE – The "ON/OFF" switch must be in the "ON" upper position to initiate and complete a brew cycle.

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
circuit and energizes the tank refill circuit. Pressing the switch again
(indicator not glowing) stops tank refilling and brewing. Stopping 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 "ON/OFF" indicator is not glowing because the tank will not

P1911

refill.

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.

Page 5

29253 111103

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.

Page 6

29253 111103

CEZ-APS/TS/TSR ADJUSTMENTS & OPTIONAL SETTINGS

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
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

The brewer is factory set with the brew lockout disabled. Brew lockout prevents starting a brew cycle if the ready
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.

Page 8

29253 111103

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

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. Press and hold the OFF/ON button. The brew valve will turn on after 10 seconds. Release the button. This begins
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. The spray is now on again and the remaining on time setting has begun. Press the OFF/ON button momentarily
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
cycles until the brew volume of step 1 is complete. Pressing the OFF/ON button again will terminate the brewing
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.

Brew Volume Setup.

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.

Page 9

29253 111103

TROUBLESHOOTING

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

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

• All electronic components have 120 volt ac and low voltage dc potential on their terminals. Shorting of

terminals or the application of external voltages may result in board failure.

• Intermittent operation of electronic circuit boards is unlikely. Board failure will normally be permanent. If an

intermittent condition is encountered, the cause will likely be a switch contact or a loose connection at a

terminal or crimp.

• Solenoid removal requires interrupting the water supply to the valve. Damage may result if solenoids are

energized for more than ten minutes without a supply of water.

• The use of two wrenches is recommended whenever plumbing fittings are tightened or loosened. This will help

to avoid twists and kinks in the tubing.

• Make certain that all plumbing connections are sealed and electrical connections tight and isolated.

• This brewer is heated at all times. Keep away from combustibles.

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. Make sure there is a nylon insulating washer under each screw head that holds the control board to the plastic
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.

Page 10

29253 091603

TROUBLESHOOTING (cont.)

REFILL CIRCUIT

PROBABLE CAUSE REMEDYPROBLEM

Will not fill or refill

1. Power off to brewer (CDBC-APS/
TC/TS/TSR & CEZ-APS/TS/TSR)

2. Water shut off (CDBC-APS/TC/
TS/TSR & CEZ-APS/TS/TSR)

3. Display flashing (CDBC-APS/TC/
TS/TSR) or ready light flashing
(CEZ-APS/TS/TSR)

4. ON/OFF Switch (CDBC-APS/TC/
TS/TSR & CEZ-APS/TS/TSR)

5. Lime build up on Probe (CDBC­APS/TC/TS/TSR & CEZ-APS/TS/
TSR)

6. Refill Valve or Control Board
(CDBC-APS/TC/TS/TSR & CEZ­APS/TS/TSR)

Press ON/OFF switch on control
panel to determine if power is ON.

Make sure water is ON.

Brewer has shut down due to
malfunction (See Diagnostic Chart
in manual, Page 19, or under top lid
of brewer).

Make sure ON/OFF Switch is "ON"
and indicator is lit.

Remove the Probe and check for
lime deposit on tip. Clean and
reinstall.

Disconnect the brewer from the
power source and remove wires
from refill valve coil. Check for con­tinuity across the terminals of the
solenoid coil. If continuity is not
present, replace the refill valve (See
page 30). If continuity is present,
the valve 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
terminals of the refill solenoid. Con­nect the brewer to the power source.
Press the switch "ON". Within five
seconds, voltage should be present
at the solenoid terminals. If voltage
is not present, refer to the wiring
diagrams and check the wiring har­ness.

Fill or refill does not shut "OFF"

(ON/OFF Switch "ON")

7. Water is too conductive for proper
operation when using the factory
setting of sensing threshold. (CDBC­APS/TC/TS/TSR)

1. Lime build up on probe (CDBC­APS/TC/TS/TSR & CEZ-APS/TS/
TSR)

Page 11

Reset the

old Adjustment Procedures

Water Sensing Thresh-

on page

9.

Remove Probe and check for lime
deposits on tip. Clean and reinstall.

29253 111103