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U3
U3A
OPERATING & SERVICE MANUAL
BUNN-O-MATIC CORPORATION
POST OFFICE BOX 3227
SPRINGFIELD, ILLINOIS 62708-3227
PHONE: (217) 529-6601 FAX: (217) 529-6644
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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 po
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INTRODUCTION This brewer will brew a three gallon batch of coffee into each reservoir (one at a time). Each reservoir has its own dispensing faucet(s).The brewer also has a hot water faucet(s) for allied beverage use. It is only for indoor use on a sturdy counter where ambient temperature is in the range of 10-30°C (50-85°F). Brewer to be installed at a location where it can be overseen by trained personnel. USER NOTICES Carefully read and follow all notices on the brewer and in this manua
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ELECTRICAL REQUIREMENTS CAUTION - The brewer must be disconnected from the power source until specified in Initial Set-Up. RED L2 RED L2 208V OR 240V 380V OR 440V 120V A.C. BLUE 208V OR 240V WHITE 208 OR L3 380V OR 440V 240V A.C. 208V OR 240V NEUTRAL 380V OR 440V BLACK 120V A.C. L1 BLACK L1 GREEN GREEN P1841 P1843 U3 & U38 requires 3-wire, grounded service rated U333 & U3833 requires 3-wire, grounded service 120/208 or 120/240 volts ac, U3-30 amp,U38-40 amp, rated 240 volt ac, 35 amp or 440
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CE REQUIREMENTS • This appliance must be installed in locations where it can be overseen by trained personnel. • For proper operation, this appliance must be installed where the temperature is between 5°C to 35°C. • Appliance shall not be tilted more than 10° for safe operation. • An electrician must provide electrical service as specified in conformance with all local and national codes. • This appliance must not be cleaned by water jet. • This appliance is not intended for use by persons (incl
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INITIAL SETUP (cont.) 6. Brewing cycles may be started whenever water temperature is correct. This condition is indicated by the dial thermometer on front of the brewer. Whenever the pointer is in the green, brewer is ready for brewing. The ° recommended brewing temperature is approximately 200 F (93°C). Water temperature may be increased by turning thermostat knob clockwise, decreased by turning knob counterclockwise. 7. When desired temperature is reached, insert funnel support, funnel and
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COFFEE BREWING 1. Brewing cycles may be started whenever water temperature is correct. This condition is indicated by the dial thermometer on front of the brewer. Whenever the pointer is in the green, brewer is ready for brewing. ® 2. Insert Bunn filter in funnel and add desired amount of coffee. 3. Level the bed of coffee and place funnel into the funnel support. Place funnel cover over the funnel and be sure the water swing spout is over the center of the funnel cover. 4. Turn "ON/OFF" swit
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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 qualified service person- nel. • All electronic components have 120 volt ac and low voltage dc potential on their terminals. Shorting of terminals or the
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TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Brew cycle will not start (cont) (A4) Check the terminal block for 2. No power or incorrect voltage to the brewer (cont) 440 volts ac across the black and blue terminals, black and red termi- nals and the red and blue terminals on four wire three phase 440 volt models. (B) Check circuit breakers or fuses. 3. Water level below pump housing. Be sure water shut-off valve is open and that the in-line filters or strain- (Water level in the
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TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Tank not filling 1.ON/OFF Switch (This switch Refer to Service - ON/OFF Switch must be in the "ON" position for for testing procedures. See page the refill circuit to operate. 22 2. No water Be sure water shut-off is open and that in-line filters or strainers are not blocking water flow. (Do not confuse water shut-off valve with the manual fill and drain valve underneath brewer). 3. Solenoid Valve Refer to Service - Solenoid Valve fo
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TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Water not hot 1. Limit Thermostat Refer to Service - Limit Thermo- CAUTION - Do not eliminate or stat for testing procedures. See bypass limit thermostat. Use only page19 Bunn-O-Matic replacement part #29329.1000 2. Control Thermostat Refer to Service - Control Ther- mostat for testing procedures. See page 17 3. Tank Heater(s) Refer to Service - Tank Heater for testing procedures. See page 30 4. Contactor Refer to Service - Contactor
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TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Check pump flow rate with a watch. 3. Pump - Flow Rate Funnels overflow (cont.) Pump flow rate should be approxi- mately 24 ounces in 15 seconds. Be sure pump assembly is free of any obstructions. 4. Soft Water When using a water softener, a coarse grind of coffee may be preferred. If required, a bypass system is available as an optional feature. Coffee reservoir overflows Be sure coffee reservoir is empty 1. Coffee reservoir not comp
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SERVICE Contents Circuit Breaker .....................................................14 This section provides procedures for testing and Contactor ..............................................................15 replacing various major components used in this Control Thermostat ...............................................17 brewer should service become necessary. Refer to Fuse and Fuse Holder ...........................................18 Troubleshooting for assistance in determining
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SERVICE (cont.) CIRCUIT BREAKER (120/208V and 120/240V Three 4. With the black wire removed, remove the other Wire Models and 440V Four Wire Models) black wire from the circuit breaker. 5. Check for continuity across the terminals on the circuit breaker. If continuity is present as described the circuit breaker is operating properly. If continuity is not present as described, press the reset button and repeat step 5, if continuity is not present as described, replace the circuit breaker.
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SERVICE (cont.) CONTACTOR a) 120 volts ac for three wire 120/208, 120/240 volt and 380 volt models. b) 230 volts ac for two wire 230 volt models. c) 208 or 240 volts ac for two wire 208 or 240 volt models. d) 220 or 254 volts ac for four wire 280 or 440 volt models. 5. Disconnect the brewer from the power source. If voltage is present as described, proceed to #6. If voltage is not present as described refer to the Wiring Diagrams and check the brewer wiring harness. 6. Check for continui
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SERVICE (cont.) CONTACTOR (cont.) Removal and Replacement: 9. Check for continuity across the terminals on the 1. Disconnect all the wires from the contactor. left side of the contactor by manually closing the 2. Remove the two #8-32 screws securing the con- contacts. Continuity must not present when the tactor to the contactor mounting bracket, remove contact is released. contactor and protective shield. Discard contac- 10. Check for continuity across the terminals on the tor. right side o
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SERVICE (cont.) not be present when the thermostat is in the "OFF" position (fully counterclockwise). CONTROL THERMOSTAT If continuity is present as described, the control ther- mostat is operating properly. If continuity is not present as described, replace the control thermostat. Removal and Replacement: 1. Disconnect the wires from the control thermo- stat. 2. Remove the thermostat capillary bulb by firmly pulling up on the capillary at the component bracket. This will disengage the gromm
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SERVICE (cont.) Removal and Replacement: FUSE AND FUSE HOLDER (208V, 240V, 230V Two Fuse: Wire Models and 380V Three Wire Models) 1. Remove the cap from the fuse holder. 2. Remove fuse from the fuse holder, inspect, if blown discard. 3. Install new 5 amp fuse in the fuse holder. 4. Reinstall fuse holder cap. Fuse Holder: 1. Disconnect the wires from the rear of the fuse holder. 2. Remove the nut securing the fuse holder to the component bracket. 3. Push fuse holder through the hole in the co
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SERVICE (cont.) LIMIT THERMOSTAT Removal and Replacement: 1. Remove the wires from the limit thermostat ter- minals. 2. Carefully slide the limit thermostat out from under the retaining clip and remove the limit thermo- stat. 3. Carefully slide the new limit thermostat into the retaining clip. 4. Refer to Fig. 11 and reconnect the wires. P2209.60 FIG. 10 LIMIT THERMOSTAT Location: The limit thermostat is located on the center front of the component bracket behind the timer mounting BLK to C
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SERVICE (cont.) LIQUID LEVEL BOARD AND LEVEL PROBE 7. Touching the free end of the jumper to the brewer's frame simulates a "FULL" condition, preventing jumper from touching the brewer's frame simulates "NEED WATER" condition. Connect the brewer to the power source, simulate the conditions in the chart below while measuring the voltage between T1 and T3 0n the liquid level board. Repeat these several times. There is an approximate five second delay for output to stabilize. Voltage - Vol
