Made in the USA!

Made in the USA
Home   |    Service Issue   |    Email A Friend    |
|    Login
Google+ Facebook Twitter Blog 1-855-727-8363     

Business Outlook
Contact Us
Food Service
Industry News
Vending Services
Wittern Group

Financing Available - Apply Now



Vending machine
Service Manual






This manual contains service and installation instructions for the Combo product line. All Combo models are equipped with an electronic control system. All programming of vend functions, pricing and features are done on the controller. Changes can be made without any additional accessories or remote parts. Selections can be priced individually from $.05 to $999.95 in five cent increments (U.S. currency).

Features Include: 

Multi Drop Bus (MDB) coin handling mechanism

Self-diagnostics and cash accountability

Multi Vend, Free Vend, Bonus Vend and Promo Vend features

Hermetically sealed refrigeration system with R-134a refrigerant

Programmable electronic control of the refrigeration unit

Motorized delivery, electronically controlled

Visual feedback when a product has been vended or when an error condition exists

No change or loss of program/memory because of power failure


Caution: This vending machine utilizes DC motors. Do not attempt to turn augers by hand. Motor damage could occur. 


Cash accountability records Total Cash transactions and Total Vend cycles performed by the vending machine. Information for individual selections, complete range (rows) or total machine can be compiled and used for inventory and ordering records.
The vending sequence is "first-in, first-out" for each selection, eliminating the need for stock rotation to maintain fresh products in the vend area.
This manual should be read thoroughly to become familiar with the functions of all components, along with the features that are available. The initial set-up of a vending machine is very important in insuring trouble-free operation of the equipment. Following the instructions at the initial installation of the machine will avoid service problems and minimize set-up time.




This vending machine was thoroughly inspected before leaving the factory and the delivering carrier has accepted this vending machine as their responsibility. Any damage or irregularities should be noted at the time & delivery and reported to the carrier. Request a written inspection report from the claims inspector to file any claim for damage. File the claim with the carrier (not the manufacturer) within 15 days after receipt of the vending machine. Carefully remove the outside packing material in a manner not to damage the finish or exterior of the vending machine. Inspect the vending machine for concealed shipping damage. Report any damage hidden by the shipping material directly to the delivering carrier on a Hidden Damage Report. Remove the "Knock-A-Way" support by sliding a pallet jack under the vending machine, inserting a screwdriver or prying tool into the groove of the Knock-A-Way and splitting it in two as shown in Figure 1. Turn the leveling screws in as far as possible. 


Vending Machines - Removing Knock-Away Supports  




Consult local, state and country codes and regulations before installing the vending machine. Please refer also to the Safety Manual & Installation Guidelines (P/N 4206816) supplied with your vending machine.


Caution: To insure reliability and maintain manufacturer's equipment warranty, vending machine must NOT be placed in and environment where the temperature is greater than 90F/32C and the relative humidity is 65% greater.


Caution: Do not block the vent openings in front of the vending machine. Always allow free ventilation behind a bank installation so that exhaust air is not trapped. Failure to do so could result in a refrigeration failure.


Warning: DO NOT USE EXTENSION CORDS. Extension cords can cause problems.


1. Position the vending machine in its place of operation no further than 6 feet (2 m) from the power outlet or receptacle.
2. Leave at least 6 inches (15 cm) of space between the back of the vending machine and any wall or obstruction for proper air circulation.
3. Retrieve the keys to the vending machine from the coin return cup.
4. Open the vending machine door and remove all internal packing material.
5. Check that the vending machine door will open fully without interference.
6. Level the vending machine. Make sure all levelers are touching the floor. The vending machine must be level for proper operation and acceptance of coins through the coin changer. When the vending machine is level, the door can be opened to any position and not move by itself. Try the door half closed, straight out and in the wide open position before deciding that the vending machine is level.


Please refer to the Safety Manual & Installation Guidelines (P/N 4206816) supplied with your vending machine. Before connecting the vending machine, the integrity of the main electrical supply must be checked for correct polarity, voltage, (earth) ground, and (amperage) circuit protection. It is recommended that these checks be repeated at 6 month intervals alon9 with the routine safety electrical testing of the equipment itself. Consult a qualified electrician to correct negative voltage, amperage, polarity, or ground (earth) checks. For proper operation of any equipment utilizing electronically controlled components, the
equipment should be placed on an isolated or dedicated noise-free circuit. A noise suppressor has been installed in this machine to compensate for any signal noise that could interfere with the normal operation of the controller.


Power Switch 

Each vending machine is equipped with a power switch located on the transformer panel along with a 3 amp breaker. The witch will shut-off the light and controller. See Figure 2. The 3 amp breaker is protection for the transformer.


Vending Machine - Power Switch 




Vend Rack 

The Vend rack has been factory set for most 20 oz bottles or 12 oz cans.


Vending Machine - Column Depth 


Important Suggestions 

When loading, fill the rear selections first. This method makes it easier to load the rack. 

Load the front rack with products that sell faster. 


1. Products featured in the Live Display must match the products being loaded.
2. The white composite Funnel Slides on each side of each product column must be clean. See Figure 3b. This assures that the product cannot bridge, blocking delivery from the product column.
3. Product container bottoms must face towards the center of the rack as shown in Figure 3a.
4. Do not store bottles in "spare" space of the cabinet. The refrigeration unit could be damaged.
5. A loading chart has been provided on the inner door to make it easier to keep track of what types of products has been loaded into the Vend Rack (Can/Bottle compartment) of the Combo. Use a dry erase marker to avoid making a permanent mark.
6. If refilling with the same product size into the same column, then load products into the columns. Skip steps 7 through 11.
7. If loading for the first time, or changing to a different product size, or to reset the product cradle (motor) to the correct position, then load one row of products in each column and test vend each column using real money.

8. Add five (5) rows of products in each column to check product spacing. Products should have not more than 114" to 112" inches of free space at the front or back of the columns as shown on Figure 3a. Adjust the back spacer, latch striker or gate assembly to achieve the required dimension. The Vend Rack has been
factory set for most 20 oz. bottles or 12 oz. cans. If vending 16.9 oz bottles, remove Filler (4211816) from the back of the inner door and install it in the Vend Rack. Follow instructions on the Filler decal.

Lift the back spacer and reposition it in the adjustment slots. Use notch markers as reference points to align it vertically. See Figure 3a.

Pull and lift up on the lower end of gate assembly (or latch striker). Use a small screwdriver as a wedge to gently pry the dimple away from the slot opening. See Figure 3a. Reposition them in the adjustment slots. Use notch markers as reference points to align it vertically.

9. If product spacing is correct, then test vend each column using real money.
10. Load the columns to full capacity.


NOTE: To prevent product jams, the "bed" area of the product cradle must be face down in each column before fully loading each with products. See Figure 3c.


CAUTION: Do not load dented or damaged cans or bottles in the columns. Possible jams could occur.


Vending Machine - Vend Rack 


Vending Machine - Delivery Mechansim 


The Live Display provides a full view of the products being dispensed along with the price and selection number of each item. To load the Live Display, simply snap the can or bottle into position from the rear. The product label must face outward toward the customer. Turn the price scroll to the correct price for each selection.

The delivery chute uses a drop (vibration) sensor to detect if a product has vended after a selection is made. The sensor is attached to the underside of the delivery chute. The drop sensor sends a signal to the controller via the drop sensor box control board when a product hits the delivery chute.


The drop sensor sensitivity is factory calibrated and should not need adjustment.


Drop Sensor Factory Setting


  1. Locate the sensor adjustment screw on the drop sensor board.
  2. Use a small flat head screwdriver to slow turn the adjustment screw clockwise (increase sensitivity) and stop when the indicator light comes on.
  3. Slowly turn the adjustment screw counter-clockwise (decrease sensitivity) and stop when the indicator light goes out. At this point begin to turn adjustment screw counter-clockwise four and a half additional turns. Test the sensor for proper operation by tapping the delivery chute. The indicator light should blink when the chute is tapped.
  4. Close the vending machine door and perform several test vends.
  5. If vending special products, the drop sensor may need the following additional adjustments:

If the machine is sending more than one product per vend request, open the vending machine door and turn adjustment screw clockwise on quarter (1/4) turn (to increase sensitivity). Test vend. Repeat procedure if necessary.

If machine fails to vend a product upon vend request, turn adjustment screw counter-clockwise turn (to decrease sensitivity). Test vend. Repeat procedure if necessary.


Vending Machine - Drop Sensor Adjustment 





To load products, lift the tray slightly and pull forward until the tray stops. The uppermost trays tilt for easier loading. Load products from front to back, making sure all items fit freely between the augers. Do not attempt to force oversize items or packages into the spaces. Do not skip a space. Place the product on the bottom of the compartment on the product augers, with the label facing the front of the machine for easy identification by the customer. See Figure 6. When finished loading each tray, lift and push it back into the cabinet. All trays must be pressed to the rear of the cabinet and properly seated in the detent position.

The size of the item being vended must be larger than the diameter of the auger being used. Undersize items could cause vend problems. If the product does not fit the auger properly, use a different pitched auger or appropriate product spacer. See the following table for augers available from your distributor or service empty. Dual type selections require a pair of matching 2-3(6" diameter augers (CCW on the left and CW on the right. Please select matching auger from Candy type.


Vending Machine - Loading Snacks 


Vending Machines - Available Augers 


Product Ejectors 

Product ejectors can be added to the end of the augers to help move the product. out.


Vending Machine Product Ejectors 



By retiming the augers, difficult-to-vend items can be dispensed more dependably. Each auger can be rotated in 20 degree increments, changing the auger position for a different "drop off" point at the front of the tray. For dual drive augers, the ideal timing is for the auger ends to meet at the center of the tray: left auger at 3 o'clock, right auger at 9 o'clock. If you have trouble vending odd sized or odd shaped items, auger retiming can be accomplished on a trial and error basis as follows:
1. Disconnect power before servicing.
2. Pull the tray containing the auger to be retimed forward to its stop.
3. Remove products from the tray.
4. Push down on the motor retaining tab to release the motor from the tray.
5. Tilt the motor back and lift up approximately 1/2" inch (1.3 cm) to disengage the auger hub from the retaining rib on in the bottom of the tray. See Figure 8

6. Separate the hub from the motor by pulling forward on the hub to disengage its spline from the motors internal gear.
7. Rotate the hub (and attached auger) to the desired timing position. Reinstall by pushing the spline into the internal gear motor.
8. Replace the motor back to its original position on the rear of the tray while making sure that the hub is correctly installed behind the hub retaining rib.
9. Push the motor retaining tab into the slotted hole.
10. Load product and push tray into its vend position (locked onto its detent).
11. Reconnect power and test vend for proper operation.


Vending Machine Auger Timing 



By changing the tray configuration, different product mixes can be accommodated.



1. Order the conversion kit from your local distributor or service entity.
2. Unplug and remove the tray assembly from the vending machine. Place the tray harness in the tray before removal.
3. Remove existing tray divider and store for possible future use.
4. Remove existing auger assemblies and store for possible future use.
5. Remove the existing "even" number motor. This motor will not be needed.
6. Dress terminals removed from the motor around the tray harness and tape in place.
7. Mode the "odd" numbered motor to the center slot of the compartment.
8. Install the auger retainer (furnished as part of the conversion kit).
9. Install auger assembly (furnished as part of the conversion kit), making sure the motor coupling properly engages the motor and is securely snapped over the vertical rail or retaining rib on the tray.
10. Replace the tray assembly into the vending machine making sure that the tray is properly located and latched and connect the tray harness.
11. Set the selection to the desired vend price and adjust the price scroll to agree.
12. Test vend the converted selections for proper operation and price settings.


NOTE: In large item selections, the selection numbers will be the "odd" numbers. For example: selections C3 and C4 are converted to a single selection C3.



1. Order the conversion kit from your local distributor or service entity.
2. Unplug and remove the tray assembly from the vending machine. Place the tray harness in the tray before removal.
3. Remove the existing auger assembly and store for possible future use.
4. Remove the auger retainer and store for possible future use.
5. Move motor from the center slot to the left slot in the compartment.
6. Add the new motor (furnished as part of the conversion kit) in the right hand slot of the compartment.
7. Properly wire the motor and switch. Refer to schematic section for wire colors and locations.
8. Add the divider furnished as part of the conversion kit.
9. Install new auger assemblies (furnished in conversion kit), making sure the motor couplings properly engage with the motor and are securely snapped over the vertical rail or retaining rib on the tray.
10. Replace the tray assembly into the vending machine making sure that the tray is properly located and latched and connect the tray harness.
11. Set the selections to the desired vend price and adjust the price scrolls.
12. Test vend the converted selection for proper operation and price settings.



By altering tray spacing, taller items can be vended. The trays can be raised or lowered in 1 inch (2.5 cm) increments to provide additional headroom fro vending taller items. When increasing the headroom between two trays, a corresponding decrease in headroom of an adjoining tray will result. 


1. Select the tray that needs adjusting. Remove any product from the tray.
2. Lift the front of the tray to expose the tray release levers located on the left and right tray rails. Swing the release levers all the way up to unlatch.
3. Lift up on the front of the tray and pull slightly forward approximately 112" inch (1.3 cm) to clear the tray stop.
4. Pull the tray out about halfway. Reach underneath the tray and squeeze the top and bottom of the tray harness plug (release tabs) and pull to disconnect it from the receptacle.

5. Pull the tray out until it tilts down. Lift the mar of the tray and remove it from the vending machine.
6. Relocate both the left and right tray rails from the left and right side walls.
a. Remove the tray rail mounting screws.
b. Pull each rail forward to disengage its rear tab from the hole in the rear wall. See Figure 6.
c. Insert rail to its new location by inserting the rear tab into the hole in the rear wall.
d. Rails must be level front to back and right side to left side.
e. Install the tray rail mounting screws.

7. Replace the tray by placing its rear rollers on the left and right rails. Connect the tray harness plug to its receptacle on the back of the cabinet by reaching underneath the tray.

8. Test vend the tray in its new position to assure that the tray plug is properly seated. 


Vending Machine - Left Wall Tray Rail 




Caution: Do not plug in or unplug the coin changer with the power on!


The controller will monitor the condition of the coin changer at all times. Any activity (coins inserted) will be recorded and stored in the controller.


Accepting bills may be removed by opening the "bill box" lid or by removing the bill box from the validator. (See manual from validator manufacturer). If the bill box is removed, make sure that it is fully latched in place when it is returned to the validator.

Trapped bills, debris or dirt can result in poor bill acceptance or bill rejection. Remove the bill box and lower housing to clear trapped bills or debris. Clean the bill path plastic parts or belts with a cloth moistened with a mild soap and water solution. Clean the magnetic head and optic sensor using a swab and isopropyl alcohol. See manual from validator manufacturer. 


Caution: Do not use any petroleum based cleaning solvents, scouting pads or stiff brushes for cleaning.




There are two modes of operation: Sales Mode and Service Mode.


The vending machine accepts deposits, pays out change, and dispenses products to customers. The 10 character scrolling display is used to communicate with the customer.

When no credit has been established and a selection is made, the price for that selection displays for approximately one second.
When credit is deposited, the amount displays. Five digits are available.
After a selection is made, the controller will determine if sufficient credit is available. If the accumulated credit is greater than or equal to the price of the selection a vend attempt will take place. If credit is less than the selection price, the price will display and the display will scroll "PLEASE INSERT MORE MONEY".
After a successful vend, the amount of change to be returned will be displayed until all coinage is paid back.
If a selection is made and a vend cannot take place, or the selection is empty (assuming that sufficient credit and change are available), then the "MAKE ALTERNATE SELECTION" message scrolls.
If the payout tubes in the coin mechanism are below the low-level sensors, the "USE CORRECT CHANGE" message will scroll.
If no motors have been assigned or if the motor has been recorded as faulty, the "MAKE ALTERNATE SELECTION" message scrolls.

The controller will not run motors that have been recorded as "jammed" or have not been assigned. A motor jam is detected when power is applied to a motor and the motor fails to return to the home position within about 9 seconds.
Motors recorded as inoperative can be reset by running a test vend of that particular selection. See the Test Vend Selections section of this manual.

Following a successful vend, the vend counter will be incremented by one (1) and the cash counter will be incremented by the price of the vended selection. The counter rollovers occur at 79,999,920 and $99,9999.95 respectively. Test vends are not included in the counter totals.

The re-settable counters track Total Vends dispensed and Total Cash collected since last reset. The vend count and cash totals will be available by individual selections, range (rows) and entire machine utilizing all the rows (i.e. row Ate J for the combo vending machine).
Following a successful vend, the re-settable vend counter will be incremented by one (1) and the re-settable cash counter will be incremented by the price of the selection vended. The counter rollovers occur at 79,999,920 and $99,999.95 respectively if never reset.



The service mode is used by the operator to change program settings and service the machine. The display is used to communicate with operator. Read the basic programming instructions listed below to set prices, view and reset accounting records, display working motors, test selection motors, dispense coins from the coin changer and to set specific selections to vend bottles or cans. Please refer to the 120 Select Programming Manual (P/N 4212619) for additional programming instructions on how to access and use the various controller features. 


To enter the SERVICE MODE, push the red service mode button once (located on the control board). If credit exists when entering the Service mode, it will be restored when the machine is returned to the Sales Mode. 


Vending Machine - Controller 


Vending Machine - Keypad in Service Mode 




Vending Machine - Program Menu Map 


DEX/UCS or DEX stands for Data Exchange/Uniform Communications Standard. Within the vending industry, it defines the transfer of information/data between a Hand Held Computer (HHC) or data collector and the electronic vending machine. Please refer to DEX/UCS section of the 120 Select Controller Programming Manual (P/N 4212619) for the list of DEXIUCS field codes, descriptions and explanations.

The vending machine controller must be in SALES MODE. Use a connecting cable and plug in an HHC or data collector to the DEX port. The DEX port is located just below the instructional decal on the control board cover. See Figure 10. The exchange of information will begin automatically. All re-settable counters are automatically cleared (set to zero).





When the temperature is above the cut-in setting, the unit is turned on. When the refrigeration unit reaches the cut-out setting, it is turned off. If the refrigeration unit runs for more than two hours without reaching the cut-out temperature, the unit is turned off for the programmed ten (10) minute defrost time. It will then be turned on automatically.


Note: To prevent damage to the refrigeration unit when it is turned off or the power interrupted, the refrigeration unit will not restart for at least three minutes regardless of temperature.



If the refrigeration unit is turned off or the power is interrupted, the refrigeration unit will not start for at least three minutes regardless of temperature to prevent damage to the refrigeration unit.


Caution: Breaking the refrigerant joints or seals on the system voids the unit's warranty. Failure to keep the condenser coil clean and free of dirt, dust or other similar debris voids the unit warranty.


Know and understand how the unit operates. Units may vary, but the operation is basically the same. Never guess at the problem. Find the symptom before attempting to repair. Most refrigeration problems are electrical. The sealed hermetic system should not be worked on outside the Factory Service Center There are three (3) Things that can go wrong with a sealed system and should be repaired only at the Factory Service Center These are the following:
1. Low Charge - usually caused by leaks. Look for oil around seals and welds. Unit will not cool properly. The capillary tube is frosted before it enters the evaporator inlet tube.
2. Restriction in System - unit frosts, then melts, not cooling properly.
3. Bad Valves - unit does not cool properly, noisy compressor














Caution: Always disconnect power source BEFORE cleaning or servicing.


Once A Month 

Clean Cabinet Interior - Wash with a cleaning solution of mild detergent and water, rinse and dry thoroughly. Odors may be eliminated by including baking soda or ammonia in the cleaning solution. Plastic parts may be cleaned with a quality plastic cleaner. Keep delivery slide area free of dirt and sticky substances. Remove and clean condensate drain hose to eliminate any deposits that may restrict condensate water flow.


Warning: Do not get the cleaning solution on electrical components.


- Snack Compartment - The vend mechanisms and trays must be wiped clean dirt and sticky substance. Any build-up can cause the mechanisms to malfunction.

- Can/Bottle Compartment - The can/bottle racks must be wiped clean of dirt and sticky substances.
- Clean Cabinet Exterior - Wash with a mild detergent and water. Rinse and dry thoroughly. Clean occasionally with a quality car wax. Plastic exterior parts may be cleaned with a quality plastic cleaner.


Every 3 Months 

- Clean Refrigeration Intake Screen

- Remove screen and clean dust and debris from screen using a soft bristle brush or a vacuum cleaner.


Every 6 Months 

- Clean the Condenser Coil and Rear Exhaust System.

- Remove the Cover Assembly and clean the condenser coil of the refrigeration unit using a soft bristle brush and/or vacuum cleaner.

- Pull the refrigeration unit and clean the rear exhaust screen of dirt and debris.

- Do not block the evaporator or any area of the airflow with product or supplies.




When ordering parts, include the following:

1. The model and serial numbers of the machine for which the parts are needed.

2. Shipping address.

3. Address where the invoice should be sent.

4. The number of parts required.

5. Always refer to the pertinent parts and/or parts manual for the correct part number and description of a specific part. When RIGHT or LEFT is used with the name of a part, it means the person is facing the machine with the door closed,

6. Any special shipping instructions.

7. Carrier desired: air or air special, truck, parcel post or rail.

8. Signature and date.

9. If a purchase order number is used, then be sure it is visible and legible.

Mail your order to:


165 North 10th Street

Waukee, IA 50263 




Please check the following:
Does your machine have at least 6 inches (15.2 cm) of clear air space behind it?
If the power is turned on at the fuse box, is the machine the only thing that does not work?
Is the machine plugged directly into the outlet?

DO NOT USE EXTENSION CORDS. Extension cords can cause problems.

Is the evaporator coil free of dust and dirt?
Is the condenser coil free of dust and dirt?
Is the compressor free of dust? A blanket of dust can prevent the compressor from cooling in between workouts.
Is the circuit breaker at the fuse box reset?
Are evaporator fans running? To check if fans are running take a small piece of paper in front of the evaporator coil and see if the evaporator fans will blow the paper away.
Is the condenser fan running? Fold a sheet of 8-1/2" x 11" paper in half. Place the paper in from of the condenser coils and see if it draws paper to it.
Is the shelf in front of the evaporator coil clear? No tools, product, or other air restricting items.
Is the cold control set as specified? Setting the temperature colder does not accelerate cooling of product but may and may cause the product to freeze. 


To Call for Service:

-         Have model number and serial number.

-         Call phone number listed below.

USA & Canada (800) 833-4411

International (515) 274-3641


The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. We reserve the right to model or improve the designs or specifications of such products at any time without notice. 



  About   Business Outlook   Contact Us   Food Service   Industry News   Parts-Service   Sale   Trimline-II   Vending Services   Wittern Group
  Site Map

Archives    Careers    FAQ    Leasing Program    Made In The USA    Copyright ©2015