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To obtain the Illustrated Parts Catalog, visit the Bunn-O-Matic website, at www.bunn.com. This is absolutely FREE, and the quickest way to obtain the catalog. Contact Bunn-O-Matic Corporation at 1-800-286-6070 to obtain a paper copy of the required Illustrated Parts Catalog mailed via U.S. Postal Service.
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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.
Do not attempt to bypass this safety device. CLEANING 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. Regular cleaning will keep your grinder looking new for years 10191 011500...
COFFEE GRINDING Turn the selector knob to align the red arrow with the desired grind. Raise the top lid and add the whole bean coffee. Close the top lid. Locate the back of a bag behind the dispense chute. (The grinder will not operate unless the bag is behind the chute.) Allow the bag to rest on the screen beneath the chute.
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 person- nel.
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TROUBLESHOOTING (cont.) PROBLEM Grinder will not start. (cont.) Grinder will not shut off. PROBABLE CAUSE 3. Bag Sensor. (cont.) 4. Motor overload protector. 1. Off/On/Start Switch 2. Bag Sensor 3. Relay REMEDY (B) Refer to Service - Bag Sensor Switch for testing and adjustment procedures.
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TROUBLESHOOTING (cont.) PROBLEM Grinder starts, but will not dis- pense. PROBABLE CAUSE 1. Hopper 2. Entrance to grind chamber 3.Shear Plate REMEDY Coffee must be poured into hopper before grinding. Foreign materials must not block the opening at the bottom of the hopper.
SERVICE This section provides procedures for testing and replacing various major components used in this grinder should service become necessary. Refer to Troubleshooting for assistance in determining the cause of any problem. COMPONENT ACCESS WARNING - Unplug the grinder before the removal of any panel or the replacement of any component.
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SERVICE (cont) BAG SENSOR SWITCH (cont.) Disconnect the grinder from the power source. If voltage is present as described, proceed to If voltage is not present as described, refer to the Wiring Diagrams and check the grinder wiring harness. Check for continuity across the terminals on the bag sensor switch.
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SERVICE (cont,) AC MOTOR AND GRIND CHAMBER (cont.) Check the voltage across the white, red or red/ black and white/blue wires on terminals L1 & L2 with a voltmeter. Connect the grinder to the power source. When the Off/On/Start switch is momentarily placed in the “START”...
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SERVICE (cont.) AC MOTOR AND GRIND CHAMBER (cont.) Remove the two .250”-20 screws (1) securing the grind selector dial plate (18) to the grind housing. Slide burr auger rotor/spring assembly (3) off of the grinder motor shaft with burr rotor cup (5), shear plate (4) and burr (7) as an assembly.
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SERVICE (cont.) AC MOTOR AND GRIND CHAMBER (cont.) 17. Install grind selector dial plate (18) with adjusting screw w/bearing (19) onto the grind chamber and secure with two .250”-20 screws (1). 18. Install grind selector knob (17) onto the grind selector dial plate (18).
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SERVICE (cont,) DC MOTOR AND GRIND CHAMBER - G1MD ONLY (cont.) 10. Remove motor and bracket out the rear of the grinder housing. 11. Remove the two .250”-20 screws securing the motor to the front of the mounting bracket. 12. Remove the two #10-32 screws securing the motor to rear of the mounting bracket.
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SERVICE (cont,) DC MOTOR AND GRIND CHAMBER - G1MD ONLY (cont.) 11. Install burr (7) on burr auger rotor/spring as- sembly (6) securing with two .250”-20 screws (5). 12. Slide burr auger rotor/spring assembly and burr (3) onto the motor shaft. 13.
SERVICE (cont,) OFF/ON/ START SWITCH FIG.10 OFF/ON/START SWITCH Location: The Off/On/Start switch is located in the up- per front wrapper above and to the right of the grind selector knob (left side when viewed from rear). Test Procedure: Disconnect the grinder from the power source. Check the voltage across the black wire on the Off/On/Start switch and the white wire or the red/ black on the relay coil with a voltmeter.
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SERVICE (cont.) RECTIFIER - G1MD ONLY FIG. 12 RECTIFIER Location: The rectifier is located inside the grinder housing mounted on the rear of the motor mounting bracket. Test Procedures: Disconnect the grinder from the power source. Remove the red wire and the black wire from the rectifier.
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SERVICE (cont,) RELAY FIG.14 RELAY Location: The relay is located on the grinder base inside the lower housing. Test Procedure: Disconnect the grinder from the power source and place a coffee bag behind the dispense chute. Check the voltage across the white/orange and white or red/black wires on terminals A &...
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SERVICE (cont,) RELAY (cont.) Removal and Replacement (120 Volt and 240V 60 Hz Models): 1. Remove the wires from the relay terminals. 2. Remove the two #6-32 screws securing the relay bracket w/relay to the grinder base and remove bracket and relay as an assembly. 3.
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