Bunn SINGLE Operating & Service Manual Download

Page: 9 / 46

Page 9

Problem

Brew cycle will not start (cont.)

Automatic refill will not operate

Remedy

Refer to

Service

- ON/OFF switch for

testing procedures. See page 31

Refer to

Service -

Start switch for

testing procedures. See page 34

Refer to

Service -

Timer for testing

procedures. See page 36 & 38

Refer to

Service -

Dispense valve for

testing procedures. See page 22

Refer to

Service

- Electronic controls

for testing procedures. See pages

23 thru 27

Check plumbing and shut-off

valves.

(A) Direction of flow arrow must be

pointing towards brewer.

(B) Remove the strainer/flow control

and check for obstructions. Clear or

replace.

Refer to

Service

- Limit thermostat

for testing procedures. See page

Refer to

Service -

Overflow protec-

tion switch for testing procedures.

See page 32

Refer to

Service

- Level control

board for testing procedures. See

page 28

Refer to

Service

- Electronic controls

for testing procedures. See page 23

thru 27

Refer to

Service

- Solenoid valve for

testing procedures. See page 33

Probable Cause

3. ON/OFF switch

4. Start switch

5. Timer

6. Dispense Valve

7. Control Assembly (Electronic)

1. No water

2. Water strainer/flow control (.330

GPM)

3. Limit thermostat (Electro/me-

chanical and Electronic)

4. Overflow protection switch

5. (A) Level control board & level

probe. (Electro/mechanical)

(B) Control Assembly (Electron-

ic)

6. Solenoid Valve

TROUBLESHOOTING (cont.)

27038 091900

Summary of Contents for SINGLE

Page 1: ...NN O MATIC CORPORATION POST OFFICE BOX 3227 SPRINGFIELD ILLINOIS 62708 3227 PHONE 217 529 6601 FAX 217 529 6644 To ensure you have the latest revision of the manual or to obtain the illustrated parts catalog please visit the Bunn O Matic website at www bunn com This is absolutely FREE and the quickest way to obtain the latest catalog and manual updates Contact Bunn O Matic Corporation at 1 800 286...

Page 2: ...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 ...

Page 3: ...Page 3 USER NOTICES The notices on this brewer should be kept in good condition Replace unreadable or damaged labels 00658 0000 12364 0000 00831 0000 00656 0000 20201 5600 27038 100407 37881 0000 ...

Page 4: ...an 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 counter top 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 com...

Page 5: ...k 3 When water stops flowing into the tank remove the front panel and proceed as directed Models with electronic control assemblies Place the tank heater switch at the top of the control assembly in the ON position and replace the front panel Models with electro mechanical thermostats Rotate the control thermostat knob fully clockwise to the ON position and replace the front panel 4 Wait approxima...

Page 6: ...t 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 ...

Page 7: ...ighted upper position NOTE The On Off switch must be in the lighted upper position to initiate and complete a brew cycle COFFEE BREWING 1 Select the desired batch size 2 Insert a BUNN filter into the funnel 3 Pour the proper amount of fresh coffee into the filter and level the bed of grounds by gently shaking 4 Slide the funnel into the funnel rails 5 Place an empty server under the funnel 6 Place...

Page 8: ...osened This will help avoid twists and kinks in the tubing Make certain that all plumbing connections are sealed and electrical connections tight and iso lated This brewer is heated at all times Keep away from combustibles WARNING Exercise extreme caution when servicing electrical equipment Disconnect power source when servicing except when electrical tests are specified Follow recommended service...

Page 9: ...bstructions Clear or replace Refer to Service Limit thermostat for testing procedures See page 30 Refer to Service Overflow protec tion switch for testing procedures See page 32 Refer to Service Level control board for testing procedures See page 28 RefertoService Electroniccontrols for testing procedures See page 23 thru 27 Refer to Service Solenoid valve for testing procedures See page 33 Probab...

Page 10: ...or testing procedures See page 32 RefertoService Limitthermostatfor testing procedures See page 30 RefertoService Controlthermostat for testing procedures See page 20 Refer to Service Control assembly for testing procedure See page 23 thru 27 Refer to Service Contactor for test procedures See page 18 Refer to Service Tank heater for testing procedures See page 35 Probable Cause 1 Selector switch 1...

Page 11: ...ainer flow control 330 GPM 2 Improper water pressure Remedy Refer to Service Triac assembly for removal and replacement See page 27 Refer to Service ON OFF switch for testing procedures See page 31 RefertoService Warmerelementfor testing procedures See page 40 RefertoService Controlthermostat for testing procedures See page 20 Refer to Service Control assembly for testing procedures See page 23 th...

Page 12: ...ded volume for each brew cycle Refer to Service Dispense valve for testing procedures See page 22 Refer to Adjustments on page 5 step 7 For test procedures see page 15 BUNN paper filters should be used for proper extraction Check sprayhead The brew cycle should be started only with an empty server under the funnel Adjust the timer as required to achievetherecommended192ozfor each 1 1 2 gallon brew...

Page 13: ...entrance with ON OFF switch in the ON position press the start switch and release it Check the water temperature immediately below the sprayhead with a thermometer The reading should not be less than 195 F 91 C The nut on back of the solenoid must be tight or it will vibrate during operation Plumbinglinesshouldnotberesting on the counter top A The brewer must be connected to a cold water line B Wa...

Page 14: ... panel or the replace ment of any component All components are accessible by the removal of the top cover front inspection panel and warmer base plate The top cover is attached with one 4 40 slotted head screw The front inspection panel is attached with four 6 32 slotted head screws The warmer base is attached with four 6 32 slot ted head screws P846 CAUTION B U N N W A R N IN G Contents Brewer Se...

Page 15: ...lve coil terminals Connect the brewer to the power source With the selector switch in the 1 or 1 1 2 gallon position place ON OFF Switch in the ON position Press and release the brew switch The indication must be a 120 volts ac for two wire 120 volt models 208 volts ac for three wire 120 208 volt models and 240 volts ac for three wire 120 240 volt models b 200 to 240 volts ac for two wire 200 or 2...

Page 16: ...2 gallon position when the switch is turned to the full right position 8 Reattach the connector to the brew timer circuit board 9 Refer to Fig 4 the next page when reconnecting the wires SERVICE cont BREW SELECTOR SWITCH Location The brew selector switch is located in the front of the hood on the right side Test Procedure 1 Disconnect the brewer from the power supply 2 Separate the connector on th...

Page 17: ...H cont P827 27038 091900 FIG 4 BREW SELECTOR SWITCH TERMINALS To Timer TAN GRY PNK WHI VIO to By Pass Valve WHI RED to Dispense Valve GRY to GRY Lead on Interface Socket PNK to PNK Lead on Interface Socket TAN to TAN Lead on Interface Socket ...

Page 18: ...r wiring harness 6 Check for continuity between the two black wires of the contactor coil If continuity is present as described reconnect one blackwiretothewhitewireorredwirefromtheterminal block and the other black wire to the black wire from the control thermostat Reinstall capillary tube into tank to line 7 above the bulb and proceed to 7 If continuity is not present as described replace the co...

Page 19: ...e the hood 4 Refer to Fig 6 when reconnecting the wires SERVICE cont CONTACTOR ASSEMBLY W MECHANICAL THER MOSTAT ONLY cont P828 27038 030901 FIG 6 CONTACTOR ASSEMBLY TERMINALS WHI L1 to Terminal Block White Insert BLK T2 to Tank Heater RED T1 to Tank Heater RED L1 to Terminal Block Red Insert BLK L2 to Limit Thermostat BLK to BLK Lead from Thermostat BLK to WHI Lead from the Two Pole 120V Terminal...

Page 20: ...r 120 240Vterminalblocksandtheredinsertontwo pole 200V 240V terminal blocks when the control thermostatisturned ON fullyclockwise Connect the brewer to the power source The indication must be a 120 volts ac for two wire 120 volt models three wire 120 208 volt models and three wire 120 240 volt models b 200 to 240 volts ac for two wire 200 or 240 volt models Voltage must not be indicated across the...

Page 21: ...ion and not kinked 7 Usinga 8 32slottedheadscrewfastenthecontrol thermostat to the component bracket 8 Refer to Fig 8 when reconnecting the wires 9 Adjust the control thermostat as required FIG 8 CONTROL THERMOSTAT TERMINALS BLU to Ready Light BLKtoREDLeadfromLiquidLevelSwitch BLK to BLK Lead on Contactor Coil BLK to Ready Light ...

Page 22: ...orcontinuityacrossthedispensevalvecoil terminals If continuity is present as described reconnect the wires to the dispense valve and proceed to 5 If continuity is not present as described replace the dispense valve 5 Check the dispense valve for coil action Connect the brewer to power source Place the ON OFF Switch in the ON position and press and release the Start Switch Listen carefully in the v...

Page 23: ...LVE 12 YES DOES WATER FLOW YES REPLACE PROBE 7 NO NO REPLACE SOLENOID VALVE 12 REPLACE CONTROL ASSEMBLY 1 Liquid Level Control Test Procedure 1 Disconnect brewer from the power source 2 With a voltmeter check the voltage across termi nals 3 4 of the electronic control assembly 1 Connect brewer to power source The indication must be a 120 volts ac for two wire 120 volt models 208 volts ac for three...

Page 24: ...ndication must be a 120 volts ac for two wire 120 volt models three wire 120 208 volt models and three wire 120 240 volt models after a delay of approximately 1 sec ond b 200 to 240 volts ac for two wire 208 or 240 volt models after a delay of approximately 1 second 10 Touch the screw head end of the probe to the brewer housing The indication must be 0 11 Move the probe away from the brewer housin...

Page 25: ...ness 4 Connect the brewer to the power source and place the tank heater switch in the ON position 5 Observe the red LED indicator on the electronic control circuit board 13 6 Disconnect the brewer from the power source If the indicator was on or blinking the temperature sensor is operating properly proceed to 7 If the indicator was off check the sensor connection on the electronic control circuit ...

Page 26: ...ter terminals 5 Connect the brewer to the power source The indication must be a 120 volts ac for two wire 120 volt models 208 volts ac for three wire 120 208 volt models and 240 volts ac three wire 120 240 volt models while the red indicator on the circuit board is on or blinking b 200 to 240 volts ac for two wire 200 or 240 volt models while the red indicator on the circuit is on or blinking 14 D...

Page 27: ...5 Stand the brewer upright 16 Reconnect the wires of the new triac assembly Refer to Fig 13 when reconnecting wires P923 O N CAUTION Failure To Comply Voids Warranty Hot Water Systems Water Tank Will Fill Automatically When Unit Is Connected To Power Coffee Brewers Fill The Water Tank In Accordance With The Installation Instructions DO NOT Turn On The Tank Heater Switch Until Water Comes From Open...

Page 28: ...lt models after a delay of approximately 1 sec ond b 200 to 240 volts ac for two wire 200 or 240 volt models after a delay of approximately 1 second 8 Touch the free end of jumper wire to the brewer housing The indication must be 0 9 Movethejumperwireawayfromthebrewerhous ing The indication must again be a 120 volts ac for two wire 120 volt models three wire 120 208 volt models and three wire 120 ...

Page 29: ...obe are operating properly If voltage is not present as described check the pink probe wire for continuity Removal and Replacement 1 Remove all wires from the level control board 2 Remove two 8 32 slotted head screws and lock washersholdinglevelcontrolboardtocomponent bracket 3 Installthenewlevelcontrolboardtothecomponent bracket Make certain that the lockwashers are betweenthelevelcontrolboardand...

Page 30: ...utton on the limit thermostat and repeat step 3 After repeating step 3 if no continuity is shown replace the limit thermostat 1 2 3 4 5 5 MINUTE S BUNN O M ATIC P N 26 20 12 0 VAC STA RT ON WARMER SELE CTO R READY CA UT IO N HO T WAT ER LIMIT THERMOSTAT P819 27038 030901 FIG 16 LIMIT THERMOSTAT FIG 17 LIMIT THERMOSTAT TERMINALS Removal and Replacement 1 Remove all wires from the limit thermostat t...

Page 31: ...grams and check the brewer wiring harness 5 With the black wire removed remove the white violet wire on the switch from the lower left termi nal 6 Check for continuity across the center and lower P843 SERVICE cont 27038 030901 left terminal with switch in the ON position Continuity must not be present when switch is in the OFF position If continuity is present as described reconnect the black wire...

Page 32: ... the overflow protection switch access will also be needed to the level control board or electronic control assembly and terminal block Test Procedure 1 Disconnect the brewer from the power source 2 Remove the wire nuts connecting the red wires from the overflow protection switch to the black wire from the terminal block and the blue wire from the thermostat or the violet wire from the electronic ...

Page 33: ...nic controlled 120 120 208 and 120 240 volt brewers red and violet on electro mechanical controlled 200 or 240 volt brewers and red and white blue on electronic controlled 200 or 240 volt brewers If continuity is not present as described replace the solenoid valve 6 Check the solenoid valve for coil action Connect the brewer to the power source Listen carefully in the vicinity of the solenoid valv...

Page 34: ...perating properly If continuity is not present as described replace the switch SERVICE cont 1 2 3 4 5 5 MINUTE S BU NN O M AT IC P N 26 20 12 0 VA C ST AR T ON WAR MER SE LE CT OR RE AD Y P823 P836 27038 030901 FIG 24 START SWITCH FIG 25 START SWITCH TERMINALS WHI ORN to Timer TL3 Electro Mechanical ORN to Interlock Assy Electronic WHI YEL to Timer TL5 Electro Mechanical YEL to Timer TL5 Electroni...

Page 35: ...resent as described proceed to 4 If voltage is not present as described refer to the wiring diagrams and check the wiring harness 4 Disconnect wires from the tank heater and check for continuity across the terminals of the tank heater If continuity is present as described reconnect the wires thetankheaterisoperatingproperly Ifcontinuity is not present as described replace the tank heater NOTE Ifth...

Page 36: ...al plate on to the component mounting bracket 3 Remove circuit board nylon spacers and dial plate 4 Install new timer circuit board as described in Digital Timer section on the following pages 5 Refer to Fig 31 when reconnecting wires 6 Install the timer setting decal provided with the replacement timer kit on the inside of the front access panel 7 Adjust timer as required Refer to Digital Timer s...

Page 37: ...tart Switch Bottom 2 2 2 1 5 1 1 1 5 2 5 MINUTES MINUTES MINUTES P N 24486 0000 120 VAC BUNN O M ATIC 3 3 3 4 4 5 5 6 6 7 8 ELECTRO MECHANICAL MINUTES BUNN O M ATIC P N 2620 120 VAC WHI VIO TL1 to ON OFF Switch WHI VIO TL1 to Warmer Element WHI TL2 To Terminal Block and Warmer Element 120V Two Pole 120 208V or 120 240V Three Pole Terminal Block RED TL2 to Terminal Block and Warmer Element 200V or ...

Page 38: ...er source The indication must be 0 volts If voltage is as described proceed to 7 If voltage is not as described disconnect the brewer from the power source and replace the timer 7 With a voltmeter check the voltage across ter minals TL1 and TL4 when the ON OFF switch is in the ON position Connect the brewer to the power source and press the START switch The indication must be as follows a 120 volt...

Page 39: ...econd 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 ha...

Page 40: ...ation The warmer element is located in the base of the brewer under the warmer plate Test Procedures 1 Disconnect the brewer from the power source 2 Use the white wire or red wire to the terminal block and the white violet wire to the warmer element 3 With a voltmeter on 120V 120 208V or 120 240V models check the voltage across the white wire and the white violet wire with the ON OFF switch in the...

Page 41: ...E L E C T O R S W WHI ORA WHI GRN WHI YEL WHI RED 1 2 3 4 5 BREW TIMER WHI WHI VIO WHI WHI WHI WHI WHI VIO WHI GRN WATER BYPASS WHI RED WHI VIO REFILL 4 3 2 1 TANK HEATER K1 K1 N O SW THERMOSTAT 1 2 3 4 LIQUID LEVEL BOARD SOL DISPENSE START SWITCH SOL ON OFF SWITCH BLK GRY TAN PNK TANK HEATER CONTACTOR LIMIT THERMOSTAT VIO 100W WARMER NOT AVAILABLE ON SINGLE TF OPTIONAL 3 SET SELECTOR SWITCH SHOWN...

Page 42: ...O SOL WHI VIO BLK WHI L1 N L2 AUXILIARY OUTLET 200 WATT MAXIMUM GREEN WHI BLK TANK HEATER SW WHI GRY GRY ELECTRONIC CONTROL ASSY 1 2 5 4 7 6 3 W H I W H I t TAN BLU WHI BRN PNK 20 PROBE RED 208 OR 240V GRN WHI BLU INTERLOCK ASSY PNK GRY LIMIT THERMOSTAT BLK 12 BLK 12 RED RED READY L E D PNK GRY BLK BLU 12 WHI YEL ORA WHI 120V WHI VIO 12 208 OR 240V WHI VIO 12 120V TANK HEATER VIO WATER BYPASS FRAC...

Page 43: ...REQUIRED FULL BATCH NO CONNECTION WHI VIO 1 4 BATCH 1 3 BATCH 1 2 BATCH 2 3 BATCH 3 4 BATCH BATCH COMMON S E L E C T O R S W WHI ORA WHI GRN WHI YEL 1 2 3 4 5 BREW TIMER WHI VIO RED RED RED WHI VIO WHI GRN WATER BYPASS WHI RED WHI VIO REFILL 4 3 2 1 TANK HEATER K1 K1 N O SW THERMOSTAT 1 2 3 4 LIQUID LEVEL BOARD SOL DISPENSE START SWITCH SOL ON OFF SWITCH GRY TAN PNK TANK HEATER CONTACTOR LIMIT THE...

Page 44: ...IO WHI GRN WHI RED WHI GRN 1 BREW TIMER 3 2 4 5 WHI VIO SOL WHI VIO BLK L1 L2 BLK TANK HEATER SW GRY GRY ELECTRONIC CONTROL ASSY 1 2 5 4 7 6 3 W H I W H I tϒ TAN BLU WHI BRN PNK 20 PROBE RED RED RED RED RED GRN WHI BLU INTERLOCK ASSY PNK GRY LIMIT THERMOSTAT BLK 12 BLK 12 RED RED READY L E D PNK GRY BLK BLU 12 WHI YEL ORA WHI VIO 12 TANK HEATER VIO WATER BYPASS FRACTIONAL BATCHES CONNECT AS REQUIR...

Page 45: ... 2 4 3 1 5 6 RED BLK RED WHI PNK RED TANK HEATER BLK AUXILIARY OUTLET 200 WATT MAXIMUM GRN WHI BLK WHI BLK WHI OPTIONAL BYPASS P1 P3 TAN GRY PNK GRINDER INTERFACE CONNECTOR GRY TAN PNK 4 1 2 3 P4 P2 WHI RED WHI VIO WHI OVERFLOW PROTECTION SWITCH D I G I T A L B R E W E R C O N T R O L C I R C U I T B O A R D SOL REFILL TRIAC 208 0R 240V A C 120V A C 120V A C SOL SOL LIMIT THERMOSTAT S W I T C H S ...

Page 46: ...BREWER CONTROL SCHEMATIC WIRING DIAGRAM J1 1 J1 24 J3 1 J3 40 D I G I T A L B R E W E R C O N T R O L C I R C U I T B O A R D WHI RED WHI RED WHI SOL REFILL TRIAC BLK TANK HEATER LIMIT THERMOSTAT BREW SOL P1 P3 TAN GRY PNK GRINDER INTERFACE CONNECTOR GRY TAN PNK 4 1 2 3 P4 P2 S W I T C H S E L E C T B A T C H TANK LEVEL SENSING WHI VIO START SW OPTIONAL DAY NIGHT SWITCH RED RED OVERFLOW PROTECTION...

Search results

Summary of Contents for SINGLE

Reviews:

Related manuals for SINGLE

Brands by name

Popular brands

Bunn SINGLE, Operating & Service Manual

Search results

Summary of Contents for SINGLE

Reviews:

Related manuals for SINGLE

Brands by name

Popular brands