BUNN ® CWTF-MV CWTF-APS-MV CWTF-TS-MV CWTF-TSR-MV OPERATING & SERVICE MANUAL BUNN-O-MATIC CORPORATION POST OFFICE BOX 3227 SPRINGFIELD, ILLINOIS 62708-3227 PHONE: (217) 529-6601 FAX: (217) 529-6644 28182.
INTRODUCTION This equipment will brew a half-gallon batch of coffee into an awaiting dispenser. It can be easily configured for 120V 15 amp, 120V 20 amp, 120/208V 20 amp or 120/240V 20 amp. The brewer has a hot water faucet for allied beverage use. It is only for indoor use on a sturdy counter or shelf. WARRANTY Bunn-O-Matic Corp.
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ELECTRICAL REQUIREMENTS CAUTION - The brewer must be disconnected from the power source until specified in Initial Set-Up. Requires 2-wire, grounded service rated 120 volts ac, 20 amp, single phase, 60 Hz. Requires 2-wire, grounded service rated 120 volts ac, 15 amp, single phase, 60 Hz. Requires 3-wire, grounded service rated 120/208 volts ac, 20 amp, single phase, 60 Hz. ELECTRICAL HOOK-UP CAUTION – Improper electrical installation will damage electronic components.
PLUMBING REQUIREMENTS These brewers must be connected to a cold water system with operating pressure between 20 and 90 psi (138 and 620 kPa) from a 1⁄2" or larger supply line. A shut-off valve should be installed in the line before the brewer. Install a regulator in the line when pressure is greater than 90 psi (620 kPa) to reduce it to 50 psi (345 kPa) . The water inlet fitting is 1⁄4" flare.
INITIAL SET-UP CAUTION - The brewer must be disconnected from the power source throughout the initial set-up, except when specified in the instructions. 1. Insert an empty funnel into the funnel rails. 2. Place an empty dispenser under the funnel. 3. Place the heater switch at the rear of the brewer in the "OFF" (lower) position and connect the brewer to the power source. 4.
2. Setting batch sizes. To set 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.
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 REMEDY Brew cycle will not start (cont.) 5. Timer Refer to Service - Timer for testing procedures. See page 26 or 27 6. Solenoid Valve Refer to Service - Solenoid Valve for testing procedures. See page 19 7. Water strainer/flow control (.222 GPM) (A) Direction of flow arrow must be pointing towards brewer. (B) Remove the strainer/flow control and check for obstructions. Clear or replace. Water is not hot 1.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Inconsistent beverage level in dispenser 1. Strainer/flow control (.222 GPM) (A) Direction of flow arrow must be pointing towards the brewer. (B) Remove the strainer/flow control and check for obstruction. Clear or replace. Consistently low beverage level in the dispenser 2. Syphon System The brewer must be level or slightly lower in front to syphon properly. 3.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Spitting or excessive steaming (cont.) 2. Control Thermostat Refer to Service - Control Thermostat for testing procedures. See page 15 Dripping from sprayhead 1. Syphon System The brewer must be level or slightly lower in front to syphon properly. 2. Lime Build-up CAUTION - Tank and tank components should be delimed regularly depending on local water conditions.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Weak beverage 1. Filter Type BUNN® paper filters must be used for proper extraction. 2. Coffee Grind A fine or drip grind must be used for proper extraction. 3. Sprayhead A six-hole stainless steel sprayhead must be used for proper extraction. 4. Funnel Loading The BUNN® paper filter must be centered in the funnel and the bed of ground leveled by gentle shaking. 5.
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Brewer is making unusal noises (cont.) 4. Tank Heater(s) Remove and clean lime off the tank heater(s). See page 21 Low beverage serving temperature (CWTF Only) 1. Warmer Refer to Service - Warmer element for testing procedures.
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SERVICE (cont.) CONTROL THERMOSTAT a) 120 volts ac for two wire 120 volt models. b) 120 volts ac for three wire 120/208 volt models or 120/240 volt models. 8. Disconnect the brewer from the power source. 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. FIG.
SERVICE (cont.
LIMIT THERMOSTAT FIG. 5 LIMIT THERMOSTAT Location: The limit thermostat is located inside the rear of the hood on the center rear of the tank lid. Test Procedures: 1. Disconnect the brewer from the power source. 2. Disconnect the blue and black wires from the limit thermostat. 3. With an ohmmeter, check for continuity across the limit thermostat terminals. If continuity is present as described, the limit thermostat is operating properly.
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SERVICE (cont.) SOLENOID VALVE FIG. 9 SOLENOID VALVE 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 both wires from the solenoid valve. Connect the brewer to the power source. With the lower warmer "ON/OFF" switch in the "ON" (upper) position press the start switch. 3. With a voltmeter, check the voltage across the two wires.
SERVICE (cont.
SERVICE (cont.) TANK HEATERS FIG. 13 TANK HEATERS Location: The tank heaters are 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 tank heater voltage across blue and white wires on 120 volt 15 amp version, black and white wires on 120 volt 20 amp version or black and blue wires on 120/208 volt or 120/240 volt version at the tank heater terminal block. Connect the brewer to the power source.
SERVICE (cont.) TANK HEATERS (cont.) 17. Refer to Fig.14 when reconnecting the tank heater wires. FIG.
SERVICE (cont.) TANK HEATER SWITCH 5. Check for continuity between the black wire removed from the limit thermostat and the black insert on the terminal block, with the tank heater switch in the "ON" (upper) position. 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. FIG.
SERVICE (cont. TANK HEATER SWITCH (cont.) 15. Reconnect the two black wires to the tank heater switch terminals. 16. Set tank assembly inside the hood on mounting brackets and secure with two #8-32 screws. 17. Reconnect the wires to the limit thermostat and tank heaters. Refer to Limit Thermostat and Tank Heater sections in this manual when reconnecting wires. 18. Reinstall the faucet tube and reconnect the water supply tube to the coil assembly. 19. Secure the sprayhead tube to the hood using hex nut. 20.
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SERVICE (cont.) 7. Reconnect the three pin connector from main wiring harness to the timer. If voltage is present as described, proceed to #8 If voltage is not present as described, refer to Wiring Diagrams and check the brewer wiring harness. TIMER (Early Models) EARLY MODELS FIG. 19 TIMER P2227.40 Location: The timer is located inside the front of the trunk on the upper right side of component bracket. Test Procedure. 1. Disconnect the brewer from the power source. 2.
SERVICE (cont.) DIGITAL TIMER (Late Models) FIG.
SERVICE (cont.) DIGITAL BREW TIMER (Late Models)(cont.) To increase a brew volume, place the ON/OFF switch in the “ON” position, press and hold the START switch until three clicks are heard. Release the switch and press it again one or more times. (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.) Each time the switch is pressed, two seconds are added to the brew time period.
SERVICE (cont.) WARMER ELEMENT(S)(CWTF MODELS ONLY) b) 120 volts ac for three wire 120/208 volt and 120/ 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 the continuity across the two terminals on the warmer element. If continuity is present as described, reconnect the wires on the warmer element.
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SCHEMATIC WIRING DIAGRAM FOR CWT-APS MV, CWTF-APS MV, CWTF-TS MV, CWTF-TSR MV Page 31 28182 090100
