Operating & service manual bunn-o-matic corporation post office box 3227 springfield, illinois 62708-3227 phone: (217) 529-6601 fax: (217) 529-6644 10737.0000l 10/01 ©1993 bunn-o-matic corporation www.Bunnomatic.Com cwt twin cwtf twin cwtf twin-aps ca ut io n caution di sc ar d de ca nt er discard d...
Page 2 introduction this equipment will brew one or two half-gallon batches of coffee simultaneously into awaiting dispensers (with just the press of a button). One side may include a hot water faucet for allied beverage use. It is only for indoor use on a sturdy counter. Warranty bunn-o-matic corp....
Page 3 user notices carefully read and follow all notices in this manual and on the equipment. All labels on the equipment should be kept in good condition. Replace any unreadable or damaged labels. #12364.0000 #00658.0000 #00656.0000 #00831.0000 10737 121598.
Page 4 electrical requirements caution - the brewer must be disconnected from the power source until specified in initial set-up. "a" models require 3-wire, grounded service rated 230 volts ac, 20 amp, three phase, 60 hz. Proceed as follows: one circuit models require one 3-wire, grounded service ra...
Page 5 models cwt & cwtf 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 l...
Page 6 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...
Page 7 10737 100801 operating controls on/off switch placing the "on/off" switch in the "off" lower position stops brewing. Stopping a brew cycle after it has been started will not stop the flow of water into the funnel until the tank syphons down to its proper level. Placing the switch in the "on" ...
Page 8 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 ...
Page 9 troubleshooting (cont.) problem brew cycle will not start (cont.) water is not hot probable cause remedy 10737 120800 refer to service - on/off switch for testing. See page 16 refer to service - start switch for testing procedures. See page 20 refer to service - timer for testing procedures. ...
Page 10 troubleshooting (cont.) problem inconsistent beverage level in dis- penser consistently low beverage level in the dispenser spitting or excessive steaming probable cause 1. Strainer/flow control (.222 gpm) 2. Syphon system 3. Lime build-up caution - tank and tank compo- nents should be delim...
Page 11 troubleshooting (cont.) problem spitting or excessive steaming (cont.) dripping from sprayhead water flows into tank continuously (on/off switch "on") water flows into tank continuously (on/off switch "off") beverage overflows dispenser probable cause 2. Control thermostat 1. Syphon system 2...
Page 12 troubleshooting (cont.) problem weak beverage dry coffee grounds remain in the funnel brewer is making unusal noises probable cause 1. Filter type 2. Coffee grind 3. Sprayhead 4. Funnel loading 5. Water temperature 1. Funnel loading 1. Solenoid 2. Plumbing lines 3. Water supply remedy bunn ®...
Page 13 troubleshooting (cont.) problem brewer is making unusal noises (cont.) low beverage serving tempera- ture probable cause 4. Tank heater 1. Warmer remedy remove and clean lime off the tank heater. See page 21 refer to service - warmer ele- ment for testing procedures. See page 27 10737 120800
Page 14 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 electri- cal equipmen...
Page 15 service (cont.) control thermostat location: the control thermostats are located inside the trunk on the left side of the component brackets. Test procedures: 1. Disconnect the brewer from the power source. 2. With a voltmeter, check the voltage across the blue wire on the control thermostat...
Page 16 on/off brew top on/off brew on/off brew front-side-rear on/off brew front-side-rear top on/lower start front-top-rear on/lower start front-top-rear on start on start on/lower start on/lower start location: the on/off switchs are located on the front of the hood. On/off switches service (cont...
Page 17 service (cont.) 10737 100801 on/off switches (cont.) test procedure: 1. Disconnect the brewer from the power source. 2. Viewing the switch from the back remove the white or red wire from the upper terminal and the black wire from the center terminal. 3. With a voltmeter, check the voltage ac...
Page 18 service (cont.) recovery booster relay (optional 2/2 & 0/6 only) fig. 8 recovery booster relay p2197 location the recovery boosters are located inside the trunk on the center of the component brackets just above the solenoid valve. Test procedures 1. Disconnect the brewer from the power sour...
Page 19 service (cont.) solenoid valves location: the solenoid valves are located inside the trunk on the lower center part of the component brackets. Test procedures: 1. Disconnect the brewer from the power source. 2. Disconnect the white and black wires from the solenoid valve. Connect the brewer ...
Page 20 aps models start switches service (cont.) on/off brew top on/off brew on/off brew front-side-rear on/off brew front-side-rear top on/lower start front-top-rear on/lower start front-top-rear on start on start on/lower start on/lower start fig. 12 start switches p2489.20 location: the start sw...
Page 21 service (cont.) tank heater 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 voltage across black and red wires on the tank heater. Connect the brewer to the pow...
Page 22 service (cont.) fig. 16 tank heater terminals p1239 location: the tank heater switches are located on the rear of the brewer on the upper left and right side of the trunk. Test procedure: 1. Disconnect the brewer from the power source. 2. Disconnect the black wire from the limit thermo- stat...
Page 23 service (cont.) 10737 120800 5. Check for continuity between the black wire re- moved 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 p...
Page 24 on on of f off t a n k use copper wire only for power supply connections use copper wire only for power supply connections 1 2 3 4 5 .5 minutes bunn-o-matic p/n 2235-120 vac 1 2 3 4 5 .5 minutes bunn-o-matic p/n 2235-120 vac b u n n c w s e r ie s r e a d y on /lo we r to p st ar t b u n n c...
Page 25 service (cont.) 10737 120800 digital brew timer (late models) p2197 fig. 21 digital brew timer location: the timers are located inside the front of the trunk on the upper right side of the component brackets. Test procedure. Note: do not remove or install wires while timer board is installed...
Page 26 10737 120800 blu/blk wire from tl5 to p1 whi/grn wire from tl4 to (whi) solenoid whi/blu wire from tl3 to (blk) solenoid whi wire from tl2 to p2 blk wire from tl1 to p3 fig. 22 digital timer wiring p2037 digital brew timer (late models)(cont.) service (cont.) 1. Modifying brew volumes. To mo...
Page 27 service (cont.) warmer elements (not used on aps models) location: the warmer elements are located under the warmer plates. Test procedures: 1. Disconnect the brewer from the power source. 2. With a voltmeter, check voltage across the white or red wire from the terminal block and the wire fr...
Page 28 whi/red (not available on cwt twin-aps) left lower warmer whi/red whi/grn p1-2 p1-3 p4-2 p4-3 schematic wiring diagram cwt/cwtf twin 0/2, 2/2, 4/2 & cwt twin-aps l1 green n l2 (faucet) thermal safety fuse blk right tank heater blk blk blk red blu blk blk sw2 rt. Limit thermostat rt. Ready in...
Page 29 p4-2 p4-3 schematic wiring diagram cwt twin 2/2 & 4/2 w/recovery booster l1 green n l2 red whi whi whi left top warmer right top warmer whi p4-1 yel yel whi/yel whi/yel whi whi red sw7 sw8 blk p5-3 p5-2 10867.0000e 12/00 © 1995 bunn-o-matic corporation 120/240 volts ac 3 wire single phase re...
Page 30 gry pin l.E.D. L.E.D. Gry pin gry pin optional indicator timer whi/red whi/grn p1-2 p1-3 schematic wiring diagram cwtf twin 0/6 l1 green (faucet) blk blk right tank heater blk blu blk blk sw2 rt. Limit thermostat rt. Ready indicator rt. Sw. & thermostat blk red left brew warmer right brew wa...
Page 31 blk whi red blu tank heater blk limit thermostat limit thermostat sw1-l sw1-r (faucet side) "keep warm" heater schematic wiring diagram cwtf twin 4/2 & 0/6 two-circuit green green l2 n l1 left l2 n l1 right 10847.0000c 12/00 © 1994 bunn-o-matic corporation two individual branch circuits requ...
Page 32 whi/red whi/grn p1-2 p1-3 schematic wiring diagram cwtf twin 0/6 with recovery booster l1 green (faucet) thermal safety fuse blk blk right tank heater blk blu blk blk sw2 rt. Limit thermostat rt. Ready indicator rt. Sw. & thermostat blk red left brew warmer right brew warmer whi p1-1 whi/red...
Page 33 whi/red whi/grn p1-2 p1-3 p4-2 p4-3 schematic wiring diagram cwtfa twin 2/2 & 4/2 l1 grn/yel l2 l3 right tank heater blk blu rt. Ready indicator rt. Sw. & thermostat red blk sw2 blu rt. Limit thermostat blu 10736.0001g 12/00 © 1993 bunn-o-matic corporation 230 volts ac 3 wire three phase red...
Page 34 blk whi/red whi/grn p1-2 p1-3 p4-2 p4-3 schematic wiring diagram cwtfa & cwtfb twin 2/2 & 4/2 l1 grn/yel l2 (faucet) thermal fuse blk right tank heater blk red blu blk blk sw2 rt. Limit thermostat rt. Ready indicator rt. Sw. & thermostat blk red 10736.0002j 12/00 © 1993 bunn-o-matic corporat...
