BUNN ® TW TWF DISCONTINUED VERSION The information in this manual is no longer current. OPERATING & SERVICE MANUAL BUNN-O-MATIC CORPORATION POST OFFICE BOX 3227 SPRINGFIELD, ILLINOIS 62708-3227 TELEPHONE: (217) 529-6601 FAX: (217) 529-6644 10510.
CONTENTS Introduction ............................................................. 2 Warranty .................................................................. 2 User Notices ............................................................ 3 Electrical Requirements ........................................... 4 Plumbing Requirements .......................................... 4 Initial Set-Up ............................................................ 5 Adjusting Brew Controls .................................
USER NOTICES Carefully read and follow all notices on the equipment and in this manual. They were written for your protection. All notices on the equipment should be kept in good condition. Replace any unreadable or damaged labels #00656.0000 #03408.0000 #00831.0000 #02822.0000 #03409.
ELECTRICAL REQUIREMENTS CAUTION - The brewer must be disconnected from the power source until specified in Initial Set-Up. 120V model brewers require 2-wire, grounded service rated 120 volt ac, 15 amp, single phase, 60 Hz. 120/208V model brewers require 3-wire, grounded service rated 120/ 208 volt, 20 amp, single phase, 60 Hz. L2 RED WHITE NEUTRAL L1 BLACK 120V.A.C. 208V.A.C. 120V.A.C. Electrical Hook-Up CAUTION – Improper electrical installation will damage electronic components. 1.
PLUMBING REQUIREMENTS (cont.) P1394 BREWERS W/FAUCET BREWERS W/OUT FAUCET P1392 INITIAL SET-UP CAUTION – The brewer must be unplugged throughout the initial set-up, except when specified in the instructions. 1. Remove the top lid from the brewer. 2. Rotate the control thermostat knob fully counterclockwise to the “OFF” position and replace the top lid. 3. Insert the funnel (empty) into the funnel rails. 4. Place an empty tea dispenser on the brewer base. Be prepared to empty the dispenser a few times.
INITIAL SET-UP (cont.) 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.
OPERATING CONTROLS A. TEA/OFF/COFFEE Switch TEA– Placing the switch in the left position allows the start switch to activate a timed brew cycle delivering .5 gallon of tea concentrate and 2.5 gallons of dilution water into the dispenser. OFF – Placing the switch in the center position stops the brew cycle. Stopping a brew cycle after it has started will not stop the flow of water into the funnel until the tank syphons down to its level.
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.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE Brew cycle(s) will not start (cont.) 6. Brew Timer A) Iced Tea B) Hot Coffee 7. Brew Solenoid Valve A) Iced Tea B) Hot Coffee 8. Internal Flow control (.195 GPM) (Hot Coffee Only) REMEDY Refer to Service - Brew Timer (Iced Tea) for testing procedures. See page 20 or 21 Refer to Service - Brew Timer (Hot Coffee) for testing procedures. See page 17 or 18 Refer to Service - Brew Solenoid Valve (Iced Tea) for testing procedures.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Dilution (Iced Tea) cycle will not start (cont.) 2. Start Switch Refer to Service - Start Switch for testing procedures. See page 27 3. Brew Timer (Iced Tea) Refer to Service- Brew Timer (Iced Tea) for testing procedures. See page 20 or 21 4. Brew Solenoid Valve (Iced Tea) Refer to Service - Brew Solenoid Valve (Iced Tea) for testing procedures. See page 16 5.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Consistently high or low beverage level in the dispenser. (cont.) 2. External Strainer/Flow Control (.750 GPM) (A) Direction of flow arrow must be pointing towards brewer. (B) Remove the strainer/flow control and check for obstructions. Clear or replace. Spitting or excessive steaming 1. Lime Build-up CAUTION - Tank and tank components should be delimed regularly depending on local water conditions.
TROUBLESHOOTING (cont.) PROBLEM Water flows into tank continuously (TEA/OFF/COFFEE Switch in the "TEA or "COFFEE" position) PROBABLE CAUSE REMEDY 1. Brew Timer A) Iced Tea Refer to Service - Brew Timer (Iced Tea) for testing procedures. See page 20 or 21 B) Hot Coffee Water flows into tank continuously (TEA/OFF/COFFEE Switch in the "OFF" position) 1. Brew Solenoid Valve A) Iced Tea B) Hot Coffee Beverage overflows dispenser Refer to Service- Brew Timer (Hot Coffee) for testing procedures.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Weak beverage 1. Filter Type BUNN® paper filters must be used for proper extraction. 2. Tea or Coffee A sufficient quantity of fresh tea leaves or coffee should be used for proper extraction. 3. Sprayhead A six-hole (or seven-hole for Models with 90 oz concentrate option) stainless steel sprayhead must be used for proper extraction. 4.
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 qualified service personnel.
SERVICE (cont.) BREW SOLENOID VALVE (HOT COFFEE) If continuity is not present as described, replace the solenoid valve. 6. Check the hot coffee solenoid valve for coil action. Connect the brewer to the power source. With TEA/OFF/COFFEE switch in the "COFFEE" position press the 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.
SERVICE (cont.) If continuity is not present as described, replace the solenoid valve. BREW SOLENOID VALVE (ICED TEA) 6. Check the iced tea solenoid valve for coil action. Connect the brewer to the power source. With TEA/ OFF/COFFEE switch in the "TEA" position press the 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 continuity is not present as described, refer to the Wiring Diagrams and check the wiring harness. SERVICE (cont.) BREW TIMER (HOT COFFEE- Early Models) 5. With a voltmeter, check the voltage across terminals TL1 and TL4 when the TEA/OFF/COFFEE switch is in the “COFFEE” position and the START switch is momentarily placed in the lower position. Connect the brewer to the power source.
SERVICE (cont.) DIGITAL BREW TIMER (HOT COFFEE -Late Models) 6. With a voltmeter, check the voltage across terminals TL1 and TL4 when the "TEA/OFF/COFFEE" switch is in the "COFFEE" position. Connect the brewer to the power 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.
SERVICE (cont.) DIGITAL BREW TIMER (HOT COFFEE - Late Models)(cont.) 1. Modifying brew volumes. To modify a brew volume, first check that the SET/LOCK switch is in the “SET” position on the circuit board. To increase a brew volume, place the TEA/OFF/ COFFEE switch in the “COFFEE” position, press and hold the START switch until three clicks are heard. Release the switch and press it again one or more times.
SERVICE (cont.) BREW TIMER (ICED TEA - Early Models) 5. With a voltmeter, check the voltage across terminals TL1 and TL4 when the TEA/OFF/COFFEE switch is in the “TEA” position and the START switch is momentarily placed in the lower position. Connect the brewer to the power source. The indication must be 120 volts ac for two wire 120 volt models and three wire 120/208 volt models for approximately twenty seconds and then return to its previous indication. 6. Disconnect the brewer from the power source.
SERVICE (cont.) 6. With a voltmeter, check the voltage across terminals TL1 and TL4 when the "TEA/OFF/COFFEE" switch is in the "TEA" position. Connect the brewer to the power source. The indication must be 0 volts. DIGITAL BREW TIMER (ICED TEA - Late Models) 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.
SERVICE (cont.) DIGITAL BREW TIMER (ICED TEA - Late Models)(cont.) 1. Modifying brew volumes. To modify a brew volume, first check that the SET/LOCK switch is in the “SET” position on the circuit board. To increase a brew volume, place the TEA/OFF/ COFFEE switch in the “TEA” position, press and hold the START switch until three clicks are heard. Release the switch and press it again one or more times.
SERVICE (cont.) 8. Disconnect the brewer from the power source. CONTROL 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. P2198.50 FIG. 14 CONTROL THERMOSTAT Location: The control thermostat is located inside hood on the right side to the left of the iced tea brew timer. Test Procedures: 1.
SERVICE (cont.) 5. Check the solenoid valve for coil action. Connect the brewer to the power source, place the TEA/ OFF/COFFEE switch in the “TEA” position and momentarily place the START switch in the lower position and release. Listen carefully in the vicinity of the solenoid valve for a “clicking” sound as the coil magnet attracts. 6. Disconnect the brewer from the power source.
SERVICE (cont.) LIMIT THERMOSTAT 5. With a voltmeter, check the voltage across the exposed terminal of the limit thermostat and the white wire from the power cord or the red wire from the terminal block. Connect the brewer to the power source. The indication must be: a) 120 volts ac for two wire 120 volt models. b) 208 volts ac for three wire 120/208 volt models. 6. Disconnect the brewer from the power source. If voltage is present as described, reconnect the blue wire to the limit thermostat.
SERVICE (cont.) TEA/OFF/COFFEE SWITCH If voltage is present as described, proceed to #6. If voltage is not present as described, refer to the Wiring Diagrams and check the wiring harness. 6. Check for continuity across the center and left terminals of the top row when switch is in the "TEA" position and the center and right terminals of the top row when the switch is in the "COFFEE” position. If continuity is present as described, replace the wires, the switch is operating properly.
SERVICE (cont.) START SWITCH 4. Check for continuity across the two terminals on the left side of the switch when it is held in the lower position. Continuity must not be present across these terminals in the upper position. If continuity is present as described, reconnect the wires, the switch is operating properly. If continuity is not present as described, replace the switch. Removal and Replacement: 1. Remove the wires from the switch terminals. 2.
SERVICE (cont.) TANK HEATER P2198.50 FIG. 24 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. With a voltmeter, check the voltage across the black and white wires on 120 volt models or the black and red wires for 120/208 volt models. Connect the brew to the power source. The indication must be: a) 120 volts ac for two wire 120 volt models . b) 208 volts ac for three wire 120/208 volt models. 3.
SERVICE (cont.) THERMAL FUSE (Models W/Faucet Only) Removal and Replacement: 1. Disconnect the thermal fuse from the right tank heater terminal and the black lead from the control thermostat. 2. Remove thermal fuse and discard. 3. Connect new thermal fuse to the right tank heater terminal and the black lead from the control thermostat 4. Refer to Fig. 27 when reconnecting wires. BLK Lead from Control Thermostat HHII FFF OOF Thermal Fuse BU BUNN NN P2198.50 FIG.
SERVICE (cont.) HALF BATCH SWITCH (Optional) 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 the switch captive in the hood. 4. Refer to FIG. 29 when reconnecting the wires. GRY to Iced Tea Brew Timer PNK to Iced Tea Brew Timer P1038 FIG.29 HALF BATCH SWITCH TERMINALS P1959.60 FIG.
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READY INDICATOR BLU BLK 10502.
