CRT5
CRTF5
INTRODUCTION
This equipment will automatically brew a half-gallon batch of coffee into an awaiting dispenser. The brewer
may include a hot water faucet for allied beverage use. It is only for indoor use on a sturdy counter or shelf.
BUNN-O-MATIC COMMERCIAL PRODUCT WARRANTY
Bunn-O-Matic Corp. (“BUNN”) warrants equipment manufactured by it as follows:
1) All equipment other than as 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 (217) 529-6601
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.
Page 2
10478 022800
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.
# 12364.0000
Page 3
ELECTRICAL REQUIREMENTS
CAUTION - The brewer must be disconnected from the power source until specified in
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:
L2 RED
WHITE
NEUTRAL
L1 BLACK
120V A.C.
208 or 240V A.C.
120V A.C.
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
L1 BLACK
200 or 240V A.C.
“A" & "B” models require 2-
wire, grounded service rated 200
volts ac or 240 volts ac, 20 amp,
single phase, 50 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. Place the heater switch at the rear of the brewer in the “OFF” lower position.
4. Remove the front panel beneath the sprayhead.
5. Feed the cord through the strain relief and connect it to the terminal block.
6. Connect the brewer to the power source and verify the voltage at the terminal block before proceeding. Replace
the front panel.
7. If plumbing is to be hooked-up later be sure the brewer is disconnected from the power source. If plumbing
has been hooked-up, the brewer is ready for Initial Set-Up.
PLUMBING REQUIREMENTS
These brewers must be connected to a cold water system with operating pressure between 20 and 90 psi (138
620 kPa) from a 1⁄2" or larger supply line. A shut-off valve should be installed in the line before the brewer. Install
a regulator in the line when pressure is greater than 90 psi (620 kPa) to reduce it to 50 psi (345 kPa). The water
inlet fitting is 1⁄4" flare.
NOTE - Bunn-O-Matic recommends 1⁄4" copper tubing for installations of less than 25 feet and 3⁄8" for more than
25 feet from the 1⁄2" water supply line. A tight coil of copper tubing in the water line will facilitate moving the brewer
to clean the countertop. Bunn-O-Matic does not recommend the use of a saddle valve to install the brewer. The
size and shape of the hole made in the supply line by this type of device may restrict water flow.
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).
Page 4
10478 022800
PLUMBING REQUIREMENTS (cont.)
P2188
MODELS W/OUT FAUCET
Models CRT5, CRT5A & CRT5B
1. Remove the shipping cap from the bulkhead
fitting on the rear of the brewer.
2. Attach the flare fitting from the short piece of
tubing on the flow control (supplied) to the water
inlet fitting at the rear of the brewer.
3. Flush the water line and securely attach it to the
flare fitting on the strainer/flow control.
4. Turn on the water supply.
P2187
MODELS W/FAUCET & INTERNAL
FLOW CONTROL
Models CRTF5 & CRTF5B
1 Remove shipping caps from the bulkhead fittings
on the rear of the brewer.
2. Attach the female flare fitting on the tube from the
needle valve to the upper fitting on the rear of the
brewer and the female flare fitting on the manifold
to the lower fitting on the rear of the brewer.
3 Flush the water supply line and securely attach it to
the male flare fitting on the manifold.
4. Turn on the water supply.
5. Place an empty vessel beneath the faucet and lift
the handle until water is dispensed.
MODELS W/FAUCET & EXTERNAL
FLOW CONTROL
Models CRTF5, CRTF5A & CRTF5B
1. Remove the shipping caps from the bulkhead
fittings on the rear of the brewer.
2. Attach the flare fitting from the short piece of
tubing on the flow control (supplied) to the lower
water inlet fitting at the rear of the brewer.
3. Attach the flare fitting from the short piece of
tubing on the tee (supplied) to the upper water
inlet fitting at the rear of the brewer.
4. Flush the water supply line and securely attach it
to the flare fitting on the tee.
5. Turn on the water supply.
6. Place an empty vessel beneath the faucet and lift
the handle until water is dispensed.
Page 5
10478 011597
INITIAL SET-UP
CAUTION - The brewer must be disconnected from the power source throughout the initial set-up, except
when specified in the instructions.
1. Insert an empty funnel into the funnel rails.
2. Place an empty dispenser under the funnel.
3. Place the heater switch at the rear of the brewer in the “OFF” lower position.
4. Connect the brewer to the power source, place the "ON/OFF" switch in the "ON" upper position, and momentarily
press and release the start switch. Water will begin flowing into the tank. When water stops flowing into the
tank, initiate a second and a third brew cycle. During the third brew cycle the tank will fill to its capacity and
the excess will flow from the sprayhead, out of the funnel, and into the dispenser.
5. When the flow of water from the funnel stops, place the heater switch at the rear of the brewer in the “ON” upper
position and wait approximately twenty minutes for the water in the tank to heat to the proper temperature.
Some water will drip from the funnel during this time, this is due to expansion and should not occur thereafter.
6. Empty the dispenser and initiate another brew cycle. Place the "ON/OFF" switch in the "ON" upper position, and
momentarily press and release the start switch.
7. Place the "ON/OFF" switch in the lower “OFF” position after water has stopped flowing from the funnel, and let
the water in the tank reheat to the proper temperature.
8. Empty the dispenser and place the "ON/OFF" switch in the "ON" upper position, and momentarily press and
release the start switch. Check the water volume in the dispenser after water has stopped flowing from the
funnel. It should be 64 ounces.
9. If not, disconnect the brewer from the power source, remove the front panel, and adjust the brew timer as
required. See Adjusting Brew Volumes . Replace the front panel, connect the brewer to the power source, and
allow the water to reheat, start, and measure another brew cycle.
10. Repeat step 9 until 64 oz water volume is achieved.
11. The brewer is now ready for use in accordance with the coffee brewing instructions on the next page.
ADJUSTING BREW VOLUMES
CAUTION - Disconnect the power source from the brewer prior to the removal of any panel for the replacement
or adjustment of any component.
NOTE: Prior to setting or modifying batch sizes, check that the brewer is connected to water supply, the tank is
properly filled, and a funnel and server are in place.
1. Modifying batch sizes. To modify a batch volume, first check that the SET/LOCK switch is in the “SET”
position on the circuit board.
To increase a batch size. Press and hold the START or BREW switch until three clicks are heard. Release the
switch (Failure to release the switch within two seconds after the third click causes the volume setting to be
aborted and previous volume setting will remain in memory) and press it again one or more times. Each time
the switch is pressed, two seconds are added to the brew time period. Allow the brew cycle to finish in order
to verify that the desired volume has been achieved.
To decrease a batch size. Press and release the START or BREW switch once for every two-second interval
to be removed from the total brew time period; then immediately press and hold down the START or BREW
switch until three clicks are heard. Release the switch. (Failure to release the switch within two seconds after
the third click causes the volume setting to be aborted and previous volume setting will remain in memory).
Allow the brew cycle to finish in order to verify that the desired volume has been achieved.
Page 6
10478 061500
ADJUSTING BREW VOLUMES(cont)
2. Setting batch sizes. To set a batch volume, first check that the SET/LOCK switch is in the “SET” position on
the circuit board. Press and hold the START or BREW switch until three distinct clicks are heard, and then
release the switch. (Failure to release the switch within two seconds after the third click causes the volume
setting to be aborted and previous volume setting will remain in memory). View the level of the liquid being
dispensed. When the desired level is reached, turn the ON/OFF switch to “OFF”. The brewer remembers this
volume and will continue to brew batches of this size until the volume setting procedure is repeated.
NOTE: When brewing coffee, batch volumes will decrease due to absorption by the coffee grounds.
3. Setting programming disable feature. If it becomes necessary to prevent anyone from changing brew times
once programmed, you can set the SET/LOCK switch to the “LOCK” position. This will prevent any programming to be done until switch is once again placed in the “SET” position.
OPERATING CONTROLS
ON/OFF SWITCH
Placing the "ON/OFF" switch in the "OFF" lower position stops brewing. Stopping a brew cycle after it has been
started will not stop the flow of water into the funnel until the tank syphons down to its proper level. Placing the
switch in the "ON" upper position supplies power to the brew station warmer and enables the brew circuit.
START SWITCH
Momentarily pressing and releasing the switch starts a brew cycle when the "ON/OFF" switch is in the "ON" upper
position.
NOTE – The "ON/OFF" switch must be in the "ON" upper position to initiate and complete a brew cycle.
COFFEE BREWING
1. Insert a BUNN® filter into the funnel.
2. Pour the fresh coffee into the filter and level the bed of grounds by gently shaking.
3. Slide the funnel into the funnel rails.
4. Place an empty dispenser beneath the funnel.
5. Place the "ON/OFF" switch in the "ON" upper position. Momentarily press and release the start 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.
3. With the sprayhead removed, insert the deliming spring (provided) all the way into the sprayhead tube. When
inserted properly, no more than two inches of spring should be visible. Saw back and forth five or six times.
NOTE – In hard water areas, this may need to be done daily. It will help prevent liming problems in the brewer
and takes less than a minute.
Page 7
10478 061500
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
PROBLEM
Brew cycle will not start
PROBABLE CAUSE
1. No water
2. No power or incorrect voltage
to the brewer
REMEDY
Water lines and valves to the
brewer must be open.
(A1) Check the terminal block for
120 volts across the black and
white terminals on two wire 120
volt brewers.
(A2) Check the terminal block for
120 volts across the red and
white terminals and the black
and white terminal on three wire
120/240 volt brewers.
(A3) Check the terminal block for
200 volts on "B Series" brewers
or 240 volts on "A Series" brewers across the red and black
terminals.
Page 8
(B) Check circuit breakers or
fuses.
10478 011597
TROUBLESHOOTING (cont.)
PROBLEM
Brew cycle will not start (cont.)
PROBABLE CAUSE
3. ON/OFF Switch
4. Start Switch
5. Timer
6. Solenoid Valve
7. Water strainer/flow control
(.222 GPM)
REMEDY
Refer to
Service
- ON/OFF
Switch for testing. See page 17
Refer to
Service
- Start Switch
for testing procedures. See page
19
Refer to
Service
- Timer for
testing procedures. See page 25
or 27
Refer to
Service
- Solenoid Valve
for testing procedures. See page
18
(A) Direction of flow arrow must
be pointing towards brewer.
(B) Remove the strainer/flow
control and check for obstructions. Clear or replace.
Water is not hot
1. Tank Heater Switch
2. (A) Limit Thermostat
(B) Thermal Cut-Off (Brewers
with Faucet)
CAUTION - Do not eliminate or
bypass limit thermostat or
thermal cut-off. Use only BOM
replacement part.
Limit Thermostat #29329.1000
Thermal Cut-Off #20211.0100
3. Control Thermostat
4. Tank Heater
Refer to
Service
- Tank Heater
Switch for testing procedures.
See page 22
Refer to
Service
- Limit Thermostat for testing procedures. See
page 16. Thermal Cut-Off for
testing procedures. See page 24
Refer to
Service
- Control Thermostat for testing procedures.
See page 14
Refer to
Service
- Tank Heater
for testing procedures. See page
20
Page 9
10478 061500
TROUBLESHOOTING (cont.)
PROBLEM
Inconsistent beverage level in
dispenser
PROBABLE CAUSE
1. Strainer /flow control (.222
GPM)
2. Syphon System
3. Lime Build-up
CAUTION - Tank and tank
components should be delimed
regularly depending on local
water conditions. Excessive
mineral build-up on stainless
steel surfaces can initiate
corrosive reactions resulting in
serious leaks.
REMEDY
(A) Direction of flow arrow must
be pointing towards the brewer.
(B) Remove the strainer/flow
control and check for obstruction. Clear or replace.
The brewer must be level or
slightly lower in front to syphon
properly.
Inspect the tank assembly for
excessive lime deposits. Delime
as required.
Consistently low beverage level
in the dispenser
Spitting or excessive steaming
4. Water Pressure
1. Timer
2. Strainer/flow Control (.222
GPM)
1. Lime Build-up
CAUTION - Tank and tank
components should be delimed
regularly depending on local
water conditions. Excessive
mineral build-up on stainless
steel surfaces can initiate
corrosive reactions resulting in
serious leaks.
Page 10
The water pressure to the
brewer must be at least 20 psi
(138 kPa).
Timer dial must indicate at least
two minutes and fifteen seconds.
(A) Direction of flow arrow must
be pointing towards brewer.
(B) Remove the strainer/flow
control and check for obstructions. Clear or replace.
Inspect tank assembly for
excessive lime deposits. Delime
as required.
10478 022800
TROUBLESHOOTING (cont.)
PROBLEM
Spitting or excessive steaming
(cont.)
Dripping from sprayhead
PROBABLE CAUSE
2. Control Thermostat
1. Syphon System
2. Lime Build-up
CAUTION - Tank and tank components should be delimed
regularly depending on local
water conditions. Excessive
mineral build-up on stainless
steel surfaces can initiate corrosive reactions resulting in
serious leaks.
3. Solenoid Valve
REMEDY
Refer to
Service
- Control
Thermostat for testing procedures. See page 14
The brewer must be level or
slightly lower in front to syphon
properly.
Inspect the tank assembly for
excessive lime deposits. Delime
as required.
Remove the solenoid valve and
clear any obstructions. Rebuild
or replace the valve if necessary.
See page 18
Water flows into tank continuously (ON/OFF Switch "ON")
Water flows into tank continuously (ON/OFF Switch "OFF")
Beverage overflows dispenser
1. Timer
1. Solenoid Valve
1.Dispenser
2. Timer
3. Solenoid Valve
Page 11
Refer to
Service -
Timer for
testing procedures. See page 25
or 27
Remove the Solenoid Valve and
clean any obstruction. Rebuild
or replace the valve if necessary.
See page 18
The dispenser must be completely empty before starting a
brew cycle.
Refer to
Service -
Timer for
testing procedures. See page 25
or 27
Remove the Solenoid Valve and
clean any obstruction. Rebuild
or replace the valve if necessary.
See page 18
10478 061500
TROUBLESHOOTING (cont.)
PROBLEM PROBABLE CAUSE
Weak beverage
1. Filter Type
2. Coffee Grind
3. Sprayhead
4. Funnel Loading
5. Water Temperature
REMEDY
BUNN® paper filters must be
used for proper extraction.
A fine or drip grind must be used
for proper extraction.
A six-hole stainless steel sprayhead must be used for proper
extraction.
The BUNN® paper filter must be
centered in the funnel and the bed
of ground leveled by gentle shaking.
Place an empty funnel on an empty
dispenser beneath the sprayhead.
Initiate a brew cycle and check the
water temperature immediately below the sprayhead with a thermometer. The reading should not
be less than 195°F (76°C). Adjust
the control thermostat to increase
the water temperature. Replace if
necessary.
Dry coffee grounds remain in
the funnel
Brewer is making unusal noises
1. Funnel Loading
1. Solenoid
2. Plumbing Lines
3. Water Supply
Page 12
The BUNN® paper filter must be
centered in the funnel and the bed
of grounds leveled by gently shaking.
The nut on the solenoid must be
tight or it will vibrate during operation.
Plumbing lines should not resting
on the counter top.
(A) The brewer must be connected
to a cold water line.
(B) Water pressure to the brewer
must not exceed 90 psi (620 kPa).
Install a regulator if necessary to
lower the working pressure to approximately 50 psi (345 kPa).
10478 022800
TROUBLESHOOTING (cont.)
PROBLEM
PROBABLE CAUSE
REMEDY
Brewer is making unusal noises
(cont.)
Low beverage serving temperature
4. Tank Heater
1. Warmer
2. ON/OFF Switch
Remove and clean lime off the
tank heater. See page 20
Refer to
Service -
Warmer
element for testing procedures.
See page 29
Refer to
Service
- ON/OFF
Switch for testing procedures.
See page 17
Page 13
10478 061500
SERVICE
This section provides procedures for testing and
replacing various major components used in this
brewer should service become necessary. Refer to
Troubleshooting
cause of any problem.
WARNING - Inspection, testing, and repair of electrical equipment should be performed only by qualified
service personnel. The brewer should be unplugged
when servicing, except when electrical tests are required and the test procedure specifically states to
plug-in the brewer.
COMPONENT ACCESS
WARNING - Disconnect the brewer from the power
source before the removal of any panel or the replacement of any component.
All components are accessible by the removal of
the top cover, front inspection panel and warmer
plate(s).
for assistance in determining the
The top cover is attached with one #4-40 screw.
The front inspection panel is attached with four #632 screws.
The warmer assembly is attached with three #4-40
screws.
Contents
Control Thermostat............................................. 14
Limit Thermostat ................................................ 16
ON/OFF Switch.................................................... 17
Solenoid (Inlet) ................................................... 18
Start Switch (Brew) ............................................ 19
Tank Heater ........................................................ 20
Tank Heater Switch ............................................. 22
Thermal Cut-Off .................................................. 24
Timer (Early Model) ............................................ 25
Digital Brew Timer (Late Model) ......................... 27
Warmer Element ................................................. 29
Wiring Diagrams................................... 30,31 & 32
CONTROL THERMOSTAT
Page 14
SERVICE (cont.)
CONTROL THERMOSTAT (cont.)
Test Procedures:
1. Disconnect the brewer from the power source.
2. Locate the blue wire on the control thermostat.
3. Check the voltage across the blue wire on the
control thermostat and the white insert on two
pole 120 volt terminal block or three pole 120/240
volt terminal blocks and the red insert on two wire
200 volt or 240 volt terminal block with a voltmeter. Connect the brewer to the power source. The
indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac for two wire 200 or 240 volt
models.
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 the
wiring diagrams and check the brewer wiring harness.
5. Locate the black wire on the control thermostat.
6. Gently remove the capillary bulb and grommet
from the tank.
7. Check the voltage across the black wire of the
control thermostat and the white insert on the two
pole 120 volt or three pole 120/240 volt terminal
block and the red insert on the two pole 200 volt or
240 volt terminal block with a voltmeter when the
control thermostat is turned fully clockwise. Connect the brewer to the power source. The indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac for two wire 200 volt or 240
volt models.
8. Disconnect the brewer from the power source.
Removal and Replacement:
1. Disconnect the control thermostat wires.
2. Remove the thermostat capillary bulb by firmly
pulling-up on the capillary at the tank lid. This will
disengage the grommet from the tank lid.
3. Remove the one #8-32 screw securing the control
thermostat to the component bracket inside the
trunk.
4. Slide the grommet to the line 4.5" above the bulb
on the new capillary tube.
5. Insert the capillary bulb through the hole in the
tank lid and press the grommet firmly and evenly
so that the groove in the grommet fits into the tank
lid.
6. Carefully bend the capillary tube so that the tube
and bulb inside the tank are in the vertical position.
NOTE - The capillary tube must be clear of any electrical termination and not kinked.
7. Using one #8-32 screw, secure the control thermostat to the component bracket inside the trunk.
8. For first type thermostat, refer to the Fig. 3 when
reconnecting thermostat wires. For second type
thermostat, it does not matter which lead is connected to which terminal.
9. Adjust the control thermostat as required.
BLU to BLU wire from Limit
Thermostat
BLK to BLK Wire from Tank
Heater (Brewers w/out Faucet)
BLK to Thermal Cut-Off from
Tank Heater (Brewers with Faucet)
First Type Thermostat
If voltage is present as described, reinstall the capillary
tube into the tank to the line 4.5" above the bulb, the
control thermostat is operating properly.
If voltage is not present as described, replace the
thermostat.
Page 15
Second Type Thermostat
P1129
FIG. 3 CONTROL THERMOSTAT TERMINALS
10478 061500
SERVICE (cont.)
LIMIT THERMOSTAT
Location:
The limit thermostat is located inside the rear of
the hood on the tank lid.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the blue and black wires from the limit
thermostat.
3. Check for continuity across the limit thermostat
terminals with a ohmmeter.
P1800
Page 16
SERVICE (cont.)
ON/OFF WARMER SWITCH
If continuity is not present as described, replace the
switch.
Removal and Replacement:
1. Remove the wires from the switch terminals.
2. Compress the clips inside the hood and gently
push the switch through the opening.
3. Push the new switch into the opening and spread
the clips to hold switch in the hood.
4. Refer to Fig.7 when reconnecting the wires.
FIG. 6 ON/OFF WARMER SWITCHES
P939
Location:
The ON/OFF switch(s) are located on the front of
the hood.
Test Procedure:
1. Disconnect the brewer from the power source.
2. Viewing the switch from the back remove the white
or red wire from the upper terminal and the black
wire from the center terminal.
3. Check the voltage across the white wire or red wire
and the black wire with a voltmeter. Connect the
brewer to the power source. The indication must
be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac for two wire 200 or 240 volt
models.4. Disconnect the brewer from the power
source.
WHI to Terminal Block (White Insert
on 120V or 120/240V Models)
RED to Terminal Block (Red Insert
on 200V or 240V)
BLK to Terminal Block
(Black Insert)
WHI/RED to Lower Center Warmer
LOWER CENTER WARMER
WHI to Terminal Block (White Insert on 120V or 120/240V Models)
RED to Terminal Block (Red Insert
on 200V or 240V
BLK to Terminal Block
(Black Insert)
YEL to Left Front Warmer
LEFT FRONT WARMER
WHI to Terminal Block (White Insert
on 120V or 120/240V Models)
RED to Terminal Block (Red Insert on
200V or 240V)
BLK to Terminal Block
(Black Insert)
WHI/VIO to Left Rear Warmer
If voltage is present as described, reconnect the white
or red 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.
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.
Page 17
LEFT REAR WARMER
WHI to Terminal Block (White Insert
on 120V or 120/240V Models)
RED to Terminal Block (Red Insert on
200V or 240V
BLK to Terminal Block
(Black Insert)
BRN/BLK to Right Front Warmer
RIGHT FRONT WARMER
WHI to Terminal Block (White Insert
on 120V or 120/240V Models)
RED to Terminal Block (Red Insert on
200V or 240V)
BLK to Terminal Block
(Black Insert)
VIO to Right Rear Warmer
RIGHT REAR WARMER
P1257.50
FIG. 7 ON/OFF WARMER SWITCH TERMINALS
10478 061500
Page 18
SERVICE (cont.)
START SWITCH
Location:
On brewers w/out fresh light the start switch is
located in the right front of the hood.
On brewers w/fresh light the start switch is located
on the right side of the hood.
Test Procedure:
1. Disconnect the brewer from the power supply.
2. Disconnect the blue wire and the white/red wire
from the switch terminals.
3. Check for continuity across the two terminals on
the switch when it is held in the "pressed-in"
position. Continuity must not be present across
these terminals in the released position.
Page 19
SERVICE (cont.)
TANK HEATER
Location:
The tank heater is located inside the tank and
secured to the tank lid.
Test Procedures:
1. Disconnect the brewer from the power supply.
2. Check the voltage across the black and white wires
on 120 volt models or the black and red wires for
120/240 volt models, 200 volt models and 240
volt models with a voltmeter. Connect the brew to
the power source. The indication must be:
a) 120 volts ac for two wire 120 volt 20 amp
models .
b) 240 volts ac for three wire 120/240 volt models.
c) 200 to 240 volts ac for two wire 200 or 240 volt
models.
3. Disconnect the brewer from the power source.
If voltage is present as described, proceed to #4
If voltage is not present as described, refer to the
Wiring Diagrams
and check wiring harness.
4. Disconnect the black wire and the white wire or red
Page 20
SERVICE (cont.)
TANK HEATER (Cont.)
13. Secure sprayhead tube to hood using a hex nut.
14. Install sprayhead.
15. Reconnect the wires to the limit thermostat, tank
heater and control thermostat. See limit thermostat and control thermostat sections in this manual
when reconnecting wires.
16. Install fill basin, secure with tank inlet fitting and
gasket. Insert water supply line through grommet
in fill basin.
17. Refer to Fig.13 when reconnecting the tank heater
wires.
WHI to Terminal Block
(White Insert on 230V
Two Wire Models)
RED to Terminal Block
(Red Insert on 120/240V
Three Wire Models or
200V and 240V Two
Wire Models
FIG. 13 TANK HEATER TERMINALS
BLK to Control Thermostat (Brewers W/Out
Faucet)
Thermal Cut-Off to BLK
from Control Thermostat (Brewers W/Faucet)
P1168.71
Page 21
10478 061500
SERVICE (cont.)
TANK HEATER SWITCH
Location:
The tank heater switch is located on the rear of
the brewer on the upper left side of the trunk.
Test Procedure:
1. Disconnect the brewer from the power source.
2. Disconnect the black wire from the limit thermostat.
3. With the tank heater switch in the "ON" positionand
with a voltmeter, check the voltage between the
black wire removed from the limit thermostat and
the white wire or red wire on the tank heater.
Connect the brewer to the power source. The
indication must be:
a) 120 volts ac on two wire 120 volt models.
b) 240 volts ac on three wire 120/240 volt models.
c) 200 to 240 volts ac on 200 volt or 240 volt
models.
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 the
Wiring Diagrams
ness.
and check the brewer wiring har-
5. With the tank heater switch in the "ON" upper
position, check for continuity between the black
wire removed from the limit thermostat and the
black insert on the terminal block. Continuity
should not be present in the "OFF" lower position.
If continuity is present as described, the tank heater
switch is operating properly.
If continuity is not present as described, replace the
tank heater switch.
Removal and Replacement:
1. Shut off and disconnect the incoming water supply to the brewer.
2. On automatic brewers gently remove the fill tube
from back of fill basin.
3. Remove the tank inlet fitting securing fill basin the
tank lid. Remove fill basin and gasket. Set all three
parts aside for reassembly.
4. On brewers with faucets, disconnect the water
supply to coil assembly and remove the tube from
the tank to the faucet.
5. Remove sprayhead and hex nut securing sprayhead tube to the hood. Set aside for reassembly.
6. Disconnect the wires on the limit thermostat and
the tank heater and the control thermostat (early
models).
7. Gently pull the thermostat sensor and grommet
from the tank lid.
8. Insert a tube to the bottom of the tank and syphon
ALL of the water out. BUNN-O-MATIC has
#12440.0000 syphon assembly available for this
purpose.
9. Remove the two #8-32 screws securing the tank
assembly to the hood.
10. Lift tank and components out as an assembly and
set aside for reassembly.
11. Disconnect the two black wires from the tank
heater switch.
12. Remove the plastic facenut, hex facenut and the
switch indicator/guard bracket that secures tank
heater switch to the rear of the brewer. Remove
switch and discard.
13. Insert new tank heater switch through the hole in
the upper left rear of the trunk and secure with
switch indicator/guard bracket, hex facenut and
plastic facenut.
Page 22
SERVICE (cont.)
TANK HEATER SWITCH (cont.)
14. Reconnect the two black wires to the tank heater
switch terminals.
15. Set tank assembly inside the hood on mounting
brackets and secure with two #8-32 screws.
16. Reconnect the wires to the limit thermostat, tank
heater and the control thermostat. Refer to limit
thermostat, tank heater and control thermostat
sections in this manual when reconnecting wires.
17. Brewers with faucet reinstall the faucet tube and
reconnect the water supply tube to the coil assembly.
18. Secure the sprayhead tube to the hood using hex
nut.
19. Install sprayhead.
20. Install fill basin, inlet gasket and secure to tank lid
with tank inlet fitting.
21. Carefully install water fill tube into the back of the
fill basin.
22. Reconnect and turn on the incoming water supply.
23. Refer to Fig. 15 when reconnecting the wires.
BLK to Limit Thermostat
BLK to Terminal Block
(Black Insert)
P1135.80
FIG. 15 TANK HEATER SWITCH TERMINALS
Page 23
10478 061500
THERMAL CUT-OFF (Brewers W/Faucet)
Location:
The thermal cut-off is located inside the hood
connected to the tank heater.
Test Procedures:
1. Disconnect the brewer from the power source.
2. Disconnect the thermal cut-off from the tank heater
and the black wire from the control thermostat.
3. Check for continuity across thermal cut-off terminals with an ohmmeter.
Page 24
SERVICE (cont.)
TIMER (Early Models)
Location:
The timer is located inside the front of the trunk
on the upper right side of component bracket.
Test Procedure.
1. Disconnect the brewer from the power source.
2. Disconnect the polarized, three pin connector from
the brewer wiring harness and rotate the brew
timer dial fully counterclockwise.
3. With a voltmeter, check the voltage across sockets
P2 & P3 (white and white/red wires) of the female
connector when the "ON/OFF" switch is in the "ON"
position (upper). Connect the brewer to the power
source. The indication must be:
a) 120 volts ac for two wire 120 volt models and
three wire 120/240 volt models.
b) 200 to 240 volts ac on two wire 200 volt or 240
volt models.
4. Disconnect the brewer from the power source.
Page 25
SERVICE (cont.)
TIMER (cont.)
If voltage is present as described, the brew timer is
operating properly. Reset the timer dial as required,
to obtain the desired brew volume.
If voltage is not present as described, replace the
timer.
Removal and Replacement:
1. Separate all connectors between the brewer wiring harness and the timer.
2. Remove the one #8-32 screw securing timer to
component bracket.
3 Install new timer circuit board as described in Late
Model Timer section on the following pages.
4. Refer to Fig. 21 when reconnecting the wires.
5. Install the Timer Setting decal provided with the
replacement timer kit, below the schematic on the
inside of the front access panel.
6. Adjust the timer as required. Refer to Late Model
Timer section on the following pages.
To Main Wiring Harness
WHI to Solenoid Valve
BLK to Solenoid Valve
OLD STYLE
FIG. 19 TIMER TERMINALS
P1136
Page 26
10478 061500
DIGITAL BREW TIMER (Late Models)
Page 27
SERVICE (cont.)
DIGITAL BREW TIMER (Late Models)(cont.)
4. Attach all wires to the replacement timer board
prior to installation to the component mounting
bracket. Refer to FIG. 21 when reconnecting the
wires.
5. Install new circuit board with spacers (as required) to the component mounting bracket.
6. Adjust the timer as described below.
Timer Setting:
NOTE: Prior to setting or modifying volumes, check
that the brewer is connected to water supply, the tank
is properly filled, and a funnel and server are in place.
NOTE: All volume settings must be done with the
sprayhead installed.
until three distinct clicks are heard and then release
the switch. (Failure to release the switch within two
seconds after the third click causes the volume setting to be aborted and previous volume setting will
remain in memory.
View the level of the liquid being dispensed. When
the desired level is reached, turn the ON/OFF switch
to “OFF”.
NOTE: Several ounces of water will continue to syphon from the tank after turning the switch “OFF”.
The brewer remembers this volume and will continue
to brew batches of this size until the volume setting
procedure is repeated.
NOTE: When brewing coffee, volume will decrease due
to absorption by the coffee grounds.
1. Modifying brew volumes. To modify a brew vol-
ume, first check that the SET/LOCK switch is in the
“SET” position on the circuit board.
To increase a brew volume, place the ON/OFF
switch in the “ON” position, press and hold the START
switch until three clicks are heard. Release the switch
and press it again one or more times. (Failure to release the switch within two seconds after the third
click causes the volume setting to be aborted and previous volume setting will remain in memory) Each time
the switch is pressed, two seconds are added to the
brew time period. Allow the brew cycle to finish in
order to verify that the desired volume has been
achieved.
To decrease a brew volume, place the ON/OFF
switch in the “ON” position, press and release the
START switch once for every two-second interval to
be removed from the total brew time period; then immediately press and hold down the START switch until
three clicks are heard. Release the switch. (Failure to
release the switch within two seconds after the third
click causes the volume setting to be aborted and previous volume setting will remain in memory). Allow
the brew cycle to finish in order to verify that the desired volume has been achieved.
2. Setting brew volumes. To set a brew volume,
first check that the SET/LOCK switch is in the “SET”
position on the circuit board. Place the ON/OFF switch
in the “ON” position, press and hold the START switch
Page 28
3. Setting programming disable feature. If it becomes necessary to prevent anyone from changing
brew time once programmed, you can set the SET/
LOCK switch to the “LOCK” position. This will prevent any further programming until switch is once
again put into the “SET” position.
BLU wire from TL5 to P1
WHI/GRN wire from TL4 to (WHI) Solenoid
WHI/BLU wire from TL3 to (BLK) Solenoid
WHI wire from TL2 to P2
WHI/RED wire from TL1 to P3
P2037
FIG. 21 DIGITAL TIMER WIRING
10478 072103
Page 29
SCHEMATIC WIRING DIAGRAM
L1
BLK
WHI
BLK
HEATER
SWITCH
CRT5, & CRTF5
(FAUCET OPTION
LIMIT
THERMOSTAT
BLK BLK
ON/OFF SWITCH
BLU
WHI/RED
WHI/RED
SWITCH AND
THERMOSTAT
"KEEP WARM" HEATER
START SWITCH
ONLY)
THERMAL
CUT-OFF
LOWER CENTER WARMER
BLUWHI/RED
TANK HEATER
T5T1
T3
BREW
TIMER
GREEN
WHI/BLU
T4
T2
NL2
WHI (MODEL 20)
RED (MODEL 35)
WHI
WHI
WHI
SOL
WHI/GRN
WHI
ON/OFF SWITCH
BLK
ON/OFF SWITCH
BLK
ON/OFF SWITCH
BLK
ON/OFF SWITCH
BLK VIO
YEL
WHI/VIO
BRN/BLK
120/240 VOLTS AC 3 WIRE
120 VOLTS AC 2 WIRE
SINGLE PHASE
LEFT FRONT
WARMER
LEFT REAR
WARMER
RIGHT FRONT
WARMER
RIGHT REAR
WARMER
WHI
WHI
WHI
WHI
WHI
WHI
Page 30
10478 072103
SCHEMATIC WIRING DIAGRAM
L1
HEATER
SWITCH
BLK
BLK WHI/RED
BLK BLK
LIMIT
THERMOSTAT
BLU
ON/OFF SWITCH
WHI/RED
WHI/RED
ON/OFF SWITCH
CRT5B, & CRTF5B
SWITCH AND
THERMOSTAT
START SWITCH
(MODEL CRTF5B ONLY)
THERMAL
CUT-OFF
LOWER CENTER WARMER
BLU
T1 T5 T3
BREW
TIMER
GREEN
TANK HEATER
WHI/BLU
T4
T2
SOL
WHI/GRN
L2
WHI
WHI
WHI
WHI
WHI
BLK
ON/OFF SWITCH
BLK
ON/OFF SWITCH
BLK
ON/OFF SWITCH
BLK
200 VOLTS AC 2 WIRE
SINGLE PHASE
YEL
WHI/VIO
BRN/BLK
VIO
LEFT FRONT
WARMER
LEFT REAR
WARMER
RIGHT FRONT
WARMER
RIGHT REAR
WARMER
WHI
WHI
WHI
WHI
WHI
Page 32
10478 072103
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