Bunn-O-Matic C, CS, CT, CWTF, CRT Service Manual

...

SERVICE & REPAIR MANUAL

BUNN-O-MATIC CORPORATION

POST OFFICE BOX 3227

SPRINGFIELD, ILLINOIS 62708-3227

PHONE: (217) 529-6601 FAX: (217) 529-6644

C, CS, CT, CWTF,

CRT, CRTF Series

Including

DV, MV, APS/TC/TS,

Single CW & Twins

Supercedes Service Manual: 41711.0000

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41711.1 110909

BUNN-O-MATIC COMMERCIAL PRODUCT WARRANTY

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

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

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

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

4) Grinding burrs on coffee grinding equipment to grind coffee to meet original factory screen sieve analysis: parts and labor for 3 years or 30,000 pounds of coffee, whichever comes ﬁ rst. These warranty periods run from the date of installation BUNN warrants that the equipment manufactured by it will be commercially free of defects in material and workmanship existing at the time of manufacture and appearing within the applicable warranty period. This warranty does not apply to any equipment, component or part that was not manufactured by BUNN or that, in BUNN’s judgment, has been affected by misuse, neglect, alteration, improper installation or operation, improper maintenance or repair, damage or casualty. This warranty is conditioned on the Buyer 1) giving BUNN prompt notice of any claim to be made under this warranty by telephone at (217) 529-6601 or by writing to Post Ofﬁ ce Box 3227, Springﬁ eld, Illinois 62708-3227; 2) if requested by BUNN, shipping the defective equipment prepaid to an authorized BUNN service location; and 3) receiving prior authorization from BUNN that the defective equipment is under warranty.

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

are not authorized to make modiﬁ cations to this warranty or to make additional warranties that are binding on BUNN. Accordingly, statements by such individuals, whether oral or written, do not constitute warranties and should not be relied upon. If BUNN determines in its sole discretion that the equipment does not conform to the warranty, BUNN, at its exclusive option while the equipment is under warranty, shall either 1) provide at no charge replacement parts and/or labor (during the applicable parts and labor warranty periods speciﬁ ed above) to repair the defective components, provided that this repair is done by a BUNN Authorized Service Representative; or 2) shall replace the equipment or refund the purchase price for the equipment.

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

In no event shall BUNN be liable for any other damage or loss, including, but not limited to, lost proﬁ ts, lost sales, loss of use of equipment, claims of Buyer’s customers, cost of capital, cost of down time, cost of substitute equipment, facilities or services, or any other special, incidental or consequential damages. AutoPOD, AXIOM, BrewLOGIC, BrewMETER, Brew Better Not Bitter, BrewWISE, BrewWIZARD, BUNN Espress, BUNN Family Gourmet, BUNN Gourmet, BUNN Pour-O-Matic, BUNN, BUNN with the stylized red line, BUNNlink, Bunn-OMatic, Bunn-O-Matic, BUNNserve, BUNNSERVE with the stylized wrench design, Cool Froth, DBC, Dr. Brew stylized Dr. design, Dual, Easy Pour, EasyClear, EasyGard, FlavorGard, Gourmet Ice, Gourmet Juice, High Intensity, iMIX, Infusion Series, Intellisteam, My Café, PowerLogic, Quality Beverage Equipment Worldwide, Safety-Fresh, savemycoffee.com, Scale-Pro, Silver Series, Single, Smart Funnel, Smart Hopper, SmartWAVE, Soft Heat, SplashGard, The Mark of Quality in Beverage Equipment Worldwide, ThermoFresh, 392, Beverage Bar Creator, Beverage Proﬁ t Calculator, BUNNSource, Coffee At Its Best, Digital Brewer Control, Nothing Brews Like a BUNN, Pouring Proﬁ ts, Respect Earth, Respect Earth with the stylized leaf and coffee cherry design, Signature Series, Tea At Its Best, The Horizontal Red Line, Titan, Ultra are either trademarks or registered trademarks of Bunn-O-Matic Corporation.

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Contents

Trouble Shooting .............................................................................................................. 4

Component Access ........................................................................................................ 10

Control Thermostat ........................................................................................................ 10

Electronic Thermostat .................................................................................................... 11

ON/OFF Switch ............................................................................................................... 12

Start Switch (Brew) ........................................................................................................ 13

Solenoid (Inlet) .............................................................................................................. 14

Tank Heater ....................................................................................................................16

Fill Basin ........................................................................................................................ 16

Tank Heater Switch ........................................................................................................ 18

Thermal Cut-Off ............................................................................................................. 20

Coil/Faucet ..................................................................................................................... 21

Limit Thermostat ............................................................................................................ 22

Recovery Booster ........................................................................................................... 23

Timer (Early Model) ....................................................................................................... 24

Freshness Timer (Early Models)..................................................................................... 25

Digital Brew Timer (Late Model) .................................................................................... 26

Warmer Elements........................................................................................................... 28

Schematic Wiring Diagrams .......................................................................................... 29

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TROUBLESHOOTING

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

• Inspection, testing, and repair of electrical equipment should be performed only by qualiﬁ ed service 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 ﬁ ttings are tightened or loosened. This will help to avoid twists and kinks in the tubing.

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

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

WARNING – • Exercise extreme caution when servicing electrical equipment.

• Unplug the brewer when servicing, except when electrical tests are speciﬁ ed.

• Follow recommended service procedures

• Replace all protective shields or safety notices

PROBLEM

Brew cycle will not start

PROBABLE CAUSE

1. No water

2. No power or incorrect voltage to the brewer

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.

(B) Check circuit breakers or fuses.

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TROUBLESHOOTING (cont.)

Brew cycle will not start (cont.)

Water is not hot

PROBABLE CAUSE

REMEDY

3. ON/OFF Switch

4. Start Switch

5. Timer

6. Solenoid Valve

7. Water strainer/ﬂ ow control (.222 GPM) Early models

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 parts.

3. Control Thermostat

4. Tank Heater

Refer to Service - ON/OFF Switch for testing.

Refer to Service - Start Switch for testing procedures.

Refer to Service - Timer for testing procedures.

Refer to Service - Solenoid Valve for testing procedures.

(A) Direction of ﬂ ow arrow must be pointing towards brewer.

(B) Remove the strainer/ﬂ ow control and check for obstructions. Clear or replace.

Refer to Service - Tank Heater Switch for testing procedures.

Refer to Service - Limit Thermostat for testing procedures. Thermal Cut-Off for testing procedures.

Refer to Service - Control Thermostat for testing procedures.

Refer to Service - Tank Heater for testing procedures.

PROBLEM

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TROUBLESHOOTING (cont.)

Inconsistent beverage level in dispenser

Consistently low beverage level in the dispenser

Spitting or excessive steaming

1. Strainer /ﬂ ow control (.222 GPM) Early models.

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.

4. Water Pressure

1. Timer

2. Strainer/ﬂ ow 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.

(A) Direction of ﬂ ow arrow must be pointing towards the brewer.

(B) Remove the strainer/ﬂ ow control and check for obstruction. Clear or replace.

The brewer must be level or slightly lower in front to syphon properly.

Inspect the tank assembly for excessive lime deposits. Delime as required.

The water pressure to the brewer must be at least 20 psi (138 kPa).

Timer must be set for at least two minutes and ﬁ fteen seconds.

(A) Direction of ﬂ ow arrow must be pointing towards brewer.

(B) Remove the strainer/ﬂ ow control and check for obstructions. Clear or replace.

Inspect tank assembly for excessive lime deposits. Delime as required.

PROBLEM

PROBABLE CAUSE

REMEDY

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TROUBLESHOOTING (cont.)

Spitting or excessive steaming (cont.)

Dripping from sprayhead

Water ﬂ ows into tank continuously (ON/OFF Switch "ON")

Water ﬂ ows into tank continuously (ON/OFF Switch "OFF")

Beverage overﬂ ows dispenser

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

1. Timer

1. Solenoid Valve

1.Dispenser

2. Timer

3. Solenoid Valve

Refer to Service - Control Thermostat for testing procedures.

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.

Refer to Service - Timer for testing procedures.

Remove the Solenoid Valve and clean any obstruction. Rebuild or replace the valve if necessary.

The dispenser must be completely empty before starting a brew cycle.

Refer to Service - Timer for testing procedures.

Remove the Solenoid Valve and clean any obstruction. Rebuild or replace the valve if necessary.

PROBLEM

PROBABLE CAUSE

REMEDY

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TROUBLESHOOTING (cont.)

Weak beverage

Dry coffee grounds remain in the funnel

Brewer is making unusal noises

1. Filter Type

2. Coffee Grind

3. Sprayhead

4. Funnel Loading

5. Water Temperature

1. Funnel Loading

1. Solenoid

2. Plumbing Lines

3. Water Supply

PROBLEM PROBABLE CAUSE

BUNN® paper ﬁ lters must be used for proper extraction.

A ﬁ ne or drip grind must be used for proper extraction.

A six-hole stainless steel sprayhead must be used for proper extraction.

The BUNN® paper ﬁ lter 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.

The BUNN® paper ﬁ lter must be centered in the funnel and the bed of grounds leveled by gently shaking.

The nut on the solenoid 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).

REMEDY

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TROUBLESHOOTING (cont.)

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.

Refer to Service - Warmer element for testing procedures.

Refer to Service - ON/OFF Switch for testing procedures.

PROBLEM

PROBABLE CAUSE

REMEDY

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SERVICE

This section provides procedures for testing and replacing various major components used in this brewer should service become necessary. Refer to Troubleshooting for assistance in determining the cause of any problem.

WARNING - Inspection, testing, and repair of electrical equipment should be performed only by qualiﬁ ed service personnel. The brewer should be unplugged when servicing, except when electrical tests are required and the test procedure speciﬁ cally states to plug-in the brewer.

COMPONENT ACCESS

WARNING - Disconnect the brewer from the power

source before the removal of any panel or the replacement of any component.

All components are accessible by the removal of the top cover, front inspection panel, warmer plate(s) and rear utility cover (Twins only).

CONTROL THERMOSTAT

FIG. 10-1 CONTROL THERMOSTAT

Location:

The control thermostat is located inside the trunk

on the upper left side of the component bracket.

Test Procedures:

1. Disconnect the brewer from the power source.

2. Disconnect the leads from control thermostat.

41711.1 052009

3. Gently remove the capillary bulb and grommet from the tank.

4. Check for continuity across the thermostat terminals. The indication must be:

a) Continuity with knob rotated fully clockwise. b) No continuity with knob rotated fully counter-

clockwise. NOTE: First style does not have the ON/ OFF feature, simply check continuity.

If continuity is not present as described, replace control thermostat. If continuity is present as described, refer to the wiring diagrams and check the brewer wiring harness.

Removal and Replacement:

1. Disconnect the control thermostat wires.

2. Remove the thermostat capillary bulb by ﬁ rmly

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 ﬁ rmly and evenly so that the groove in the grommet ﬁ ts into the tank lid.

6. Carefully bend the capillary tube so that the tube and bulb inside the tank are in the vertical position.

NOTE - The capillary tube must be clear of any electrical termination and not kinked.

7. Using #8-32 screw(s), secure the control thermostat to the component bracket inside the trunk.

8. For ﬁ rst type thermostat, refer to Wiring Diagrams when reconnecting thermostat wires.

9. Adjust the control thermostat as required.

NOTE: First type will only turn approximately one

turn. Clockwise to the stopper is approximately 180° F, maximum counterclockwise to stopper is approximately 200° F.

Later types will be approximately 200° F when

turned maximum clockwise. Turning it counterclockwise until it clicks will turn off (open contacts).

Page 11

SERVICE (cont.)

OPTIONAL ELECTRONIC THERMOSTAT (ERT):

The ERT is located inside the trunk on the upper left side of the component bracket.

Test Procedures:

1. Disconnect the brewer from the power source.

2. Gently remove the temperature sensor and grommet from the tank.

3. Check voltage across the blue wire from limit thermostat and the white wire at the terminal block. Connect the brewer to the power source. The indication must be: 120Vac.

If voltage is not present as described, refer to the wiring diagrams and check the brewer wiring harness If voltage is present as described, proceed to #4.

4. Disconnect the brewer from the power source.

5. With the temperature sensor and grommet still out of the tank, check voltage across the black wire to the heater and the white wire at the terminal block. Connect the brewer to the power source. The indication must be: 120Vac.

If voltage is not present as described, replace ERT. If voltage is present as described, the ERT is functioning properly.

Removal and Replacement:

1. Disconnect the control thermostat wires.

2. Remove the temperature sensor by ﬁ rmly pullingup on the metal sheath at the tank lid. This will disengage the grommet from the tank lid.

3. Remove the one #8-32 screw securing the ERT to the component bracket inside the trunk.

4. Slide the grommet to the top of the sheath.

5. Insert the temperature sensor through the hole in the tank lid and press the grommet ﬁ rmly and evenly so that the groove in the grommet ﬁ ts into the tank lid.

6. Using the #8-32 screw, secure the ERT to the component bracket inside the trunk.

7. For ﬁ rst type thermostat, refer to Wiring Diagrams when reconnecting ERT wires.

8. Adjust the ERT as required.

FIG 11-1 THERMOSTAT TERMINALS

First Type

Second Type

Third Type

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ERT

NOTE: The ERT has a range of 170° - 210°F. Use care

not to set it too high or boiling could occur.

Page 12

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.

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 harness.

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. If continuity is not present as described, replace the switch.

SERVICE (cont.) ON/OFF WARMER SWITCH

FIG. 12-1 ON/OFF WARMER SWITCHES

FIG. 12-2 WARMER SWITCH TERMINALS

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.

(3) WHI to Neutral or RED to L2

(2) BLK to L1

(1) To Warmer

WARMER SWITCH

(1) LOAD (WARMER)

(2) LINE (L1)

(3) NEUTRAL (L2)

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SERVICE (cont.)

START SWITCHES

Location: CRT/CRTF

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.

Location: CT/CWT/CWTF/TWINS

On most "CT" series brewers, the start switch is

located in the front of the hood. On some "convertible" or "CS" brewers, the start switch is located on either the right or left side of the hood. NOTE: Optional on the left and right side warmer housings on 0/6 TWINS, connected in parallel to front mounted start switches.

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.

If continuity is present as described, reconnect the blue wire and the white/red to the switch terminals. If continuity is not present as described, replace the switch. Removal and Replacement:

1. Remove the blue wire and white/red from the start

switch.

2. Remove round retaining nut from the front of

the switch and remove switch and internal tooth lockwasher from the inside of the hood.

3. Push new switch with internal tooth lockwasher

through the hole in the hood and secure with round retaining nut.

4. Refer to Fig. 11 when reconnecting the wires.

FIG. 13-1 START SWITCH

FIG. 13-2 START SWITCH TERMINALS

BLU to Timer P1

WHI/RED to Timer P3

(3) WHI to Neutral or RED to L2

(2) BLK to L1

START SWITCH

CT SERIES

CRT/CRTF

CT/CWT/CWTF/TWINS

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SERVICE (cont.)

SOLENOID VALVES

Location: The solenoid valve is located inside the trunk on the lower center part of the component bracket.

Test Procedures:

1. Disconnect the brewer from the power source.

2. Disconnect the white and black wires from the solenoid valve. With the "ON/OFF" switch in the "ON" upper position press the start switch.

3. Check the voltage across the white and black wires 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 Wiring Diagrams and check brewer wiring harness.

5. Check for resistance across the solenoid valve coil terminals.

If resistance is present as described, reconnect the white and black wire from the timer. If resistance is not present as described, replace the solenoid valve.

6. Check the solenoid 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 solenoid valve for a" clicking" sound as the coil magnet attracts.

7. Disconnect the brewer from the power source.

If the sound is heard as described and water will not pass through the solenoid valve, there may be a blockage in the water line before the solenoid valve or, the solenoid valve may require inspection for wear, and removal of waterborne particles. If the sound is not heard as described, replace the solenoid valve.

Removal and Replacement:

1. Remove the white and black from the solenoid valve.

2. Turn off the water supply to the brewer.

3. Disconnect the water lines to and from the solenoid valve.

4. Remove the two #8-32 screws securing the solenoid mounting bracket to the component bracket. Remove solenoid bracket and solenoid valve as an assembly.

5. Remove the two #10-32 screws and lockwashers securing the solenoid valve to the solenoid bracket.

6. Using two #10-32 screws and lockwashers install new solenoid valve on solenoid mounting bracket.

7. Using two #8-32 screws install solenoid valve and bracket to the component bracket.

8. Securely fasten the water lines to and from the solenoid valve.

9. Refer to Fig. 9 when reconnecting the wires.

FIG. 14-1 SOLENOID VALVE

FIG. 14-2 SOLENOID VALVE TERMINALS

WHI from Timer

BLK from Timer

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EARLY MODELS LATE MODELS

Page 15

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120VAC - 1.18K 240VAC - 3.76K

120VAC - 247 240VAC - 757

120VAC - 334

SERVICE (cont.)

SOLENOID VALVES

Disassembly:

1. Use of the basin wrench 01060.0000 is recommended for disassembly of early style valves as illustrated below.

2. Disconnect from power source and turn off the water supply to the brewer.

3. Disconnect the water lines to and from the solenoid valve.

4. Remove the two #8-32 screws securing the solenoid mounting bracket to the component bracket. Remove solenoid bracket and solenoid valve as an assembly.

5. Remove the two #10-32 screws and lock washers securing the solenoid valve to the solenoid bracket.

6. Disassemble the valve according to the illustrations that correspond to the particular valve you have.

7. On early style valves, leave the ﬁ ttings installed in the base to use as leverage. DO NOT CLAMP

THE BASE WITH LOCKING PLIERS AS THIS CAN CAUSE DAMAGE!

8. Refer to Illustrated Parts Catalogs for replacement solenoids and repair/rebuild kits.

FIG. 15-1 FIRST STYLE

FIG. 15-2 THIRD STYLE

FIG. 15-2 SECOND STYLE

Page 16

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 brewer 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 mod-

els.

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 wires from the tank heater terminals.

5. Check resistance value across tank heater terminals and compare to chart.

FIG. 16-2 TANK HEATER

FILL BASIN

FIG. 16-1 TANK HEATER

Disassembly:

1. Use of the basin wrench 01060.0000 is recommended for removal of the ﬁ ll basin.

2. Disconnect from power source and turn off the water supply to the brewer.

3. Remove top cover.

4. Use the basin wrench (as shown above) turning counterclockwise to remove inlet ﬁ tting.

5. Lift basin off of the tank inlet.

6. Use new inlet gasket when reinstalling.

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Page 17

1800W-120V 7.40 - 8.70 1850W-220V 24.40 -28.40

3500W-200V 10.70 -12.36 3500W-240V 15.36 -17.90

HEATER RESISTANCE

If resistance is present as described, reconnect the wires, the tank heater is ok. If resistance is not present as described, replace the tank heater.

NOTE- If any resistance is read between sheath and either terminal, remove and inspect heater for cracks in the sheath.

Removal and Replacement:

1. Disconnect the water supply tube from the ﬁ ll

basin.

2. Remove the tank inlet ﬁ tting securing the ﬁ ll basin

to the tank lid, remove ﬁ ll basin and tank inlet gasket. Set all three parts aside for reassembly.

3. On brewers with faucet, shut-off water supply

to the brewer and disconnect the inlet and outlet water lines to the faucet coil assembly.

4. Disconnect the black wire on the limit thermostat

from the tank heater switch. On late model brewers also disconnect the blue wire from the limit thermostat to the control thermostat.

5. Disconnect the black wire and the white or red

wire from the tank heater terminals.

6. Remove sprayhead and the hex nut securing the

sprayhead tube to the hood. Set aside for reassembly.

7. Remove the eight #8-32 nuts securing the tank lid

to the tank.

8. Remove the tank lid with limit thermostat, spray-

head tube, tank heater, coil assembly and control thermostat w/bracket (early models only).

9 Remove the two hex nuts securing the tank heater

to the tank lid. Remove tank heater with gaskets and discard.

10. Install new tank heater with gaskets on the tank

lid and secure with two hex nuts.

SERVICE (cont.)

TANK HEATER (Cont.)

FIG. 17-2 TANK HEATER TERMINALS

11. Install tank lid with limit thermostat, sprayhead tube, tank heater, coil assembly (brewers with faucet) and control thermostat with bracket (early brewers only) using eight #8-32 hex nut.

12. Reconnect the inlet and outlet water lines to the faucet coil assembly.

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 ﬁ ll basin, secure with tank inlet ﬁ tting and gasket. Insert water supply line through grommet in ﬁ ll 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

BLK to Control Thermostat (Brewers W/ Out Faucet) Thermal Cut-Off to BLK from Control Thermostat (Brewers W/ Faucet)

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FIG. 17-1 TANK HEATER RESISTANCE

TERMINAL TO SHEATH - INFINITE (OPEN)

Page 18

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" position and 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 mod-

els.

c) 200 to 240 volts ac on 200 volt or 240 volt

models.

4. Disconnect the brewer from the power source.

If voltage is not present as described, proceed to #5. If voltage is present as described, the switch is working properly.

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 ﬁ ll tube from back of ﬁ ll basin.

3. Remove the tank inlet ﬁ tting securing ﬁ ll basin the tank lid. Remove ﬁ ll 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.

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.

14. Reconnect the two black wires to the tank heater switch terminals.

FIG 18-1 TANK HEATER SWITCH

41711.1 052009

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