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Bunn FMD-4 Operating & Service Manual

Summary of FMD-4

  • Page 1

    Operating & service manual bunn-o-matic corporation post office box 3227 springfield, illinois 62708-3227 phone: (217) 529-6601 fax: (217) 529-6644 www.Bunnomatic.Com to obtain the illustrated parts catalog, visit the bunn-o-matic website, at www.Bunn.Com. This is absolutely free, and the quickest w...

  • Page 2

    2 35135 100407 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) compresso...

  • Page 3

    3 introduction this equipment dispenses hot beverages or soups on demand from powdered product. It is for indoor use only on a sturdy counter or shelf. This equipment must be installed to comply with the basic plumbing code of the building officials and code administrators international, inc. (boca)...

  • Page 4

    4 initial set-up 1. Locate the drip tray assembly inside the dispenser door. 2. Remove the drip tray and the drip tray cover and set them aside. Electrical requirements caution - the dispenser must be disconnected from the power source until specified in initial set-up. The 120 volt version of this ...

  • Page 5

    5 initial fill & heat caution - the dispenser must be disconnected from the power source throughout the initial set-up, except when specified in the instructions. 1. Turn-on the water supply and connect the dispenser to the power source. 2. Water will automatically flow into the tank to the proper l...

  • Page 6

    6 cold beverage set-up (optional) cold beverages may be dispensed from the left dispense position. Simply place the hot/cold switch near the left whipper chamber in the “cold” (upper) position. Cleaning refer to the decal on the rear of the dispenser door for cleaning recommendations and procedures....

  • Page 7

    7 draining the hot water tank caution - the dispenser must be disconnected from the power source throughout these steps. 1. Disconnect the dispenser from the power source. 2. Place the tank heater switch in the “off” position. 3. Shut-off and disconnect the incoming water supply. 4. Remove the front...

  • Page 8

    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 elect...

  • Page 9

    9 troubleshooting (cont.) problem product will not dispense (cont.) water is not hot probable cause 5. Solenoid valve (inlet) 6. Control board #1 and probe 7. Auger drive 8. Water strainer 9. Lime build-up caution - tank and tank compo- nents should be delimed regularly depending on local water cond...

  • Page 10

    10 troubleshooting (cont.) problem water is not hot (cont.) spitting or excessive steaming dripping from dispense tip water flows into tank continuously probable cause 4. Tank heater switch 5. Relay (120v versions only) 6. Control board #2 (120v versions only) 1. Lime build-up caution - tank and tan...

  • Page 11

    11 troubleshooting (cont.) problem product overflows container weak product probable cause 1. Dispense switch 2. Dispense solenoid valve 1. Water temperature 2. Whipper motor 3. Frother 4. Dispense solenoid valve 5. Auger drive 6. Auger spring 7. Auger motor 8. Rinse/run switch 9. Rinse timer 10. Re...

  • Page 12

    12 troubleshooting (cont.) problem dispenser is making unusual noises excess dust display not lit probable cause 1. Plumbing lines 2. Water supply 3. Tank heater 1. Fan 1. Lamp 2. Lamp holder 3. Starter - lamp 4. Ballast remedy plumbing lines should not be resting on the counter top. (a) the dispens...

  • Page 13

    13 service this section provides procedures for testing and replacing various major components used in this dispenser should service become necessary. Refer to troubleshooting for assistance in determining the cause of any problem. Warning - inspection, testing, and repair of electri- cal equipment ...

  • Page 14

    14 service auger drive components - fmd-4 (cont.) 5. Check the voltage across the positive (red wire) terminal and the negative (black wire) terminal on the auger motor with a voltmeter. With the rinse/ run switch in the run (lower) position press and hold the dispense switch. Connect the dispenser ...

  • Page 15

    15 service (cont.) red to brn/whi from control board #1 j3-3 red to whi/red from control board #1 j3-2 red to whi/orn from control board #1 j3-1 red to whi/yel from control board #2 j3-3 blk to grn from control board j3-4 p1639 fig. 3 auger motor terminals fig. 4 auger drive components location the ...

  • Page 16

    16 service (cont.) auger drive components - fmd-4 & fmd-5 (cont.) 4. Disconnect the dispenser from the power sup- ply. If voltage is present as described and the auger does not turn, replace the auger motor. If voltage is not present as described, refer to the wiring diagrams and check the dispenser...

  • Page 17

    17 service (cont.) auger drive components - fmd-4 & fmd-5 (cont.) auger drive motor (refer to fig. 5) 1. Remove all hopper assemblies (20) and set aside for reassembly. 2. Remove the four #8-32 screws securing the hopper support plate (19), remove plate and set aside for reassembly. 3. Remove the fo...

  • Page 18

    18 location the front door lamp ballast is located behind the front access panel on the left front side of the com- ponent bracket. Test procedure 1. Disconnect the dispenser from the power source. 2. Disconnect the two black lead on the ballast from the main harness. 3. Check for continuity between...

  • Page 19

    19 control thermostat - fmd-4 & fmd-5 fig. 9 control thermostat p2635 location the control thermostat is located at the upper left rear of the dispenser housing. Test procedure 1. Disconnect the dispenser from the power source. 2. Disconnect the black wire of the control thermostat from the black le...

  • Page 20

    20 6. Disconnect the four pin connector from j4 of control board #1. 7. Check the voltage across pins 1 & 4 of the four pin connector on the wiring harness with a voltmeter. Connect the dispenser to the power source. The indication must be 120 volts ac for two wire 120 volt models, three wire 120/20...

  • Page 21

    21 service (cont.) 16. Reconnect the ten pin connector of the wiring harness to j2 of control board #1. 17. Gently pull the liquid level probe out of the tank lid and inspect for corrosion. Replace it if necessary. 18. Place the probe so that neither end is in contact with any metal surface of the d...

  • Page 22

    22 j4 j1 j2 j3 j4 j1 j2 j3 tank heater relay control circuitry (control board #2) (120v dispensers only): 1. Disconnect the dispenser from the power source. 2. Disconnect the six pin connector from j3 of control board #2. 3. Check the voltage across pins 5 & 6 of the six pin connector on the wiring ...

  • Page 23

    23 test procedure: 1. Disconnect the dispenser from the power source. 2. Open the dispenser door and remove the bottom door cover. 3. Disconnect the wires from the door intercon- nect wiring harness to the dispense switch to be tested. 4. Check for voltage across the black and red/white wires for th...

  • Page 24

    24 service (cont.) dispense switches (cont.) 7. Check for continuity across the terminals (top right to top left; bottom right to bottom left) of the dispense switch with the switch in the “on” position. Continuity must not present when the switch is in the “off” released position. If continuity is ...

  • Page 25

    25 service (cont.) fan fig. 15 fan location: the fan is located inside the dispenser housing on the center rear of the dispenser base plate. Test procedures: 1. Disconnect the dispenser from the power source. 2. Disconnect the black and white wires from the fan terminals. 3. Check the voltage across...

  • Page 26

    26 service (cont.) frother and whipper motor - fmd-4 (shown) & fmd-5 fig. 17 frother and whipper motor location: the frothers are located behind the dispenser door, mounted on the front panel inside the whipper chamber. The whipper motors are located on the back side of the whipper motor mounting pa...

  • Page 27

    27 service (cont.) frother and whipper motor - fmd-4 (shown) & fmd-5 (cont.) fig.19 whipper motor terminals p1221 4. Disconnect vacuum hose (12) from fan baffle (13). 5. Remove the steam collector (1) by pulling it forward and at the same time twisting it clockwise. 6. Pull the mixing chamber (2) ou...

  • Page 28

    28 service (cont.) increase/decrease switch fig. 20 increase/decrease switch p2635 location: the increase/decrease switch is located on the lower left front of the whipper motor mounting panel. Test procedure: 1. Disconnect the dispenser from the power source. 2. Disconnect the wires from the switch...

  • Page 29

    29 lamp holders fig. 22 lamp holders p2638 3 4 6 5 1. Door assy 2. Lamp holders 3. Lamp 4. Upper panel 5. Lower panel 6. Starter w/socket 2 1 location: the lamp holders are located on the front of the upper panel behind the display panel. Test procedure: 1. Disconnect the dispenser from the power so...

  • Page 30

    30 9. Reconnect the plug on the door wiring harness to the connector on the door interconnect wiring harness. 10. Install the door lower panel (5) using six #8-32 screws. Lamp starter and socket (refer to fig. 22) location: the lamp starter (6) is located inside the door assy (1) on the top of the d...

  • Page 31

    31 service (cont.) limit thermostat fig. 23 limit thermostat p2635 location: the limit thermostat is located in the center of the tank lid. Test procedures: 1. Disconnect the dispenser from the power source. 2. Disconnect both black wires from the limit ther- mostat. 3. Check for continuity across t...

  • Page 32

    32 service (cont.) p2635 rinse/run switch fig. 25 rinse/run switch location: the rinse/run switch is located on the lower center of the whipper motor mounting panel. Test procedures: 1. Disconnect the dispenser from the power source. 2. Check for continuity between the center left terminal and left ...

  • Page 33

    33 service (cont.) fig. 27 hot/cold switch p2635 hot/cold switch (optional) location: the hot/cold switch is located on the left side of the whipper motor mounting panel. Test procedure: 1. Disconnect the dispenser from the power source. 2. Disconnect the four pin plug from the hot/cold switch and t...

  • Page 34

    34 solenoid valve (cold water - optional) fig. 29 cold water solenoid valve p2635 location: the cold water solenoid valve is located on the left side of the dispenser base just behind the component bracket. Test procedures: 1. Disconnect the dispenser from the power source. 2. Disconnect the white a...

  • Page 35

    35 solenoid valve (dispense) - fmd-4 & fmd-5 fig. 31 dispense solenoid valve location: the dispense solenoid is located on the upper left center of the tank. Test procedures: 1. Disconnect the dispenser from the power source. 2. Disconnect the two wires from the solenoid valve that is being tested. ...

  • Page 36

    36 service (cont.) fig. 32 dispense solenoid valve terminals p1672 removal and replacement: 1. Remove the four #8-32 screws securing the side access panel to the housing. Remove panel and set aside. 2. Remove the wires from the solenoid valve. 3. Turn-off the water supply to the dispenser. 4. Using ...

  • Page 37

    37 p2641 fig. 34 inlet solenoid valve terminals service (cont.) whi from main harness 7. Disconnect the dispenser from the power source. If the sound is heard as described and water will not pass through the solenoid valve, there may be a block- age in the water line before the solenoid valve or, th...

  • Page 38

    38 removal and replacement: 1. Disconnect the dispenser from the power source. 2. Disconnect the water supply tube on the tank lid. 3. Disconnect the black wires on the limit therm- stat. 4. Disconnect the black wire and the white or red wire from the tank heater terminals. 5. Disconnect the pink wi...

  • Page 39

    39 service (cont.) fig. 38 tank heater switch terminals p1219 blk to main harnesss blk from main harness fig. 37 tank heater switch tank heater switch p2635 location: the tank heater switch located inside the dispenser on the upper right of the front panel. Test procedure: 1. Disconnect the dispense...

  • Page 40

    40 tank heater relay (120v dispensers only) fig. 39 tank heater relay p2635 location: the tank heater relay is located behind the lower front access cover, mounted on the left rear side of the component bracket. Test procedure: 1. Disconnect the dispenser from the power source. 2. Place the tank hea...

  • Page 41

    41 transformer fig. 41 transformer p2635 location: the transformer is located behind the lower front access cover, mounted on the right rear side of the component bracket. Test procedure: 1. Disconnect the dispenser from the power source. 2. Disconnect the four wires of the main harness from the tra...

  • Page 42

    42 35135 111103.

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    43 35135 111103.

  • Page 44

    44 35135 012103.

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    45 35135 012103.

  • Page 46

    46 35135 100407 grn gry whi/gry brn/blk brn/blk blk i n c d e c increase/ decrease switch rinse/program/ run switch run run pgm pgm rinse rinse whi/vi o red/bl k gr n grn grn grn gry pnk whi/orn whi/orn whi/red whi/red whi/gry whi/vio gry whi/gry whi/vio whi/vio whi vio whi whi/blk whi/grn whi/blk w...