Page 1
To ensure you have the latest revision of the Operating Manual, or to view the Illustrated Parts Catalog, Programming Manual, or Service Manual, please visit the Bunn-O-Matic website, at www.bunn.com. This is absolutely FREE, and the quickest way to obtain the latest catalog and manual updates. For Technical Service, contact Bunn-O-Matic Corporation at 1-800-286-6070.
AS SPECIFIED HEREIN, TO REPAIR, REPLACEMENT OR REFUND. In no event shall BUNN be liable for any other damage or loss, including, but not limited to, lost profits, lost sales, loss of use of equipment, claims of Buyer’s customers, cost of capital, cost of down time, cost of substitute equipment, facilities or services, or any other special, incidental or consequential damages.
INTRODUCTION Safety first! To avoid electrical shock, unplug dispenser from power source before servicing inside. Basic Maintenance In order to maintain proper machine operation, a Preventative Maintenance schedule must be performed on a regular basis. The following procedures pretain to all versions in the Nitron family of machines unless otherwise noted. CONTENTS Warranty ...........................2 User Notices ..........................3...
Recommended Daily Cleaning Instructions The use of a damp cloth rinsed in any mild, non-abrasive, liquid detergent is recommended for cleaning all sur- faces on Bunn-O-Matic equipment. Do NOT clean this equipment with a water jet device. 1. Open dispenser door.
REQUIRED REGULAR MAINTENANCE: When performing Daily-Weekly Cleaning procedures, inspect o-rings, seals, and bushings for signs of wear or damage and replace immediately. Check and/or replace every 6 months or as required: 39690.0000 Pump Tube Replacement Kit (Includes items indented below) 28755.1011 Tube, Norprene .25"...
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.
Page 7
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE 1. Compressor ON/OFF switch. Refrigeration Check for "ON" position or no con- Dispense stations not working. tinuity - replace switch. Note: Cooling failure or excessive 2. Dirty condenser filter or fins. bath and cabinet temperatures for Clean filter and fins or replace con- more than 4 hours will result in denser filter.
Page 8
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Dispenser Locked Out 1. Check Dispense Lockout switch. (A) Set switch to ON position. Dispense stations not working. (B) Check switch and harness for proper continuity. Cooling system failure. 1. Refrigeration or cold water recir- Check all previous items that pre- culation system.
Page 9
TROUBLESHOOTING (Continued) PROBLEM PROBABLE CAUSE REMEDY Dispense station Water solenoid Replace solenoid (24vdc) or check concentrate only wire connection between water valve and main control board. Dispense station Concentrate out Replace refill concentrate container water only or BIB Product pump not pumping Check for proper counterclockwise rotation of pump rollers.
Page 10
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Water leak filling drip tray or around 1. Initial fill/setup Some expansion normal. May fill dispense deck area drip tray during initial ice block formation 2. Dispense deck Inspect or replace fittings clamps, o-rings, solenoids and quick discon- nect fittings.
Page 11
TROUBLESHOOTING (cont.) PROBLEM PROBABLE CAUSE REMEDY Unit is not working 1. Step-down transformer. Check for 120/24 or 230/24 vac. If no 24vac reading, replace step-down transformer. 2. Main control board. If 24 vac present and no LED’s lit, replace control board. Difficulty brixing and/or weak bev- 1.
Page 12
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Only Water Flowing from Faucet 1. Bag-in-Box (BIB) or caddy is 1. Change BIB to full BIB or refill empty. the caddy with more product. 2. BIB or caddy is not engaged in 2. Lift BIB or caddy out of adapt- bottle adapter properly.
Page 13
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Coffee is Weaker than Desired 1. BIB or caddy is empty. 1. Change to full BIB or replenish caddy with more product. 2. Product pump tubing is worn. 2. Contact authorized service agent or perform product tub- ing replacement if authorized to do so.
Page 14
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Nothing Flowing from Nozzles 1. Dispense switch is OFF. 1. Turn Dispense switch ON. 2. Gas, coffee, and water not 2. Assure all required connec- connected. tions are made according to set-up instructions before op- erating the system.
Page 15
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Irregular Flow from Nozzle 1. The product pump speed is set 1. Use a more appropriate con- 1. Flow is pulsating/ hammering too high (at max) to dispense centrate (between 4:1 to 11:1) a lower ratio product (below and adjust the product dial to 4:1).
Page 16
TROUBLESHOOTING (cont.) PROBLEM REMEDY PROBABLE CAUSE Unit Performing Inconsistently 1. System was installed/set-up 1. a) Install a water line that is (Brix/Nitro fluctuating wildly or incorrectly or has been placed in accordance with machine outside normal range) in an environment with unac- specifications.
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 electrical equipment should be performed only by qualified service personnel.
SERVICE(CONT.) ACCESS PANELS Location: Before removing panels, make sure power is OFF to the machine and water is disconnected accept where indicated in testing procedures. Retain all screws and other attaching hardware for re-assembly. FIG. 1 ACCESS PANELS 55124 021418...
SERVICE (CONT.) Cabinet Fan Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Remove the four screws attaching the fan and cover assembly. 3. Gently pull the cover forward and disconnect the 2-pin connector from the main wiring harness. 4.
SERVICE (CONT.) Compressor FIG. 7 START RELAY TERMINALS Compressor Start Relay: Refer to FIG. 7 1. Disconnect the dispenser from the power source. 2. Remove compressor terminal cover (1). 3. Install meter leads as shown and check for low nominal resistance through the PTC relay. If continuity is not present, replace the PTC relay.
Page 22
SERVICE (CONT.) Compressor (Cont.) Removal and Replacement: Compressor Relay: Refer to FIG. 9 1. Remove the terminal cover (1) 2. Disconnect the white wire from the compressor relay. 3. Pull relay (2) off of the compressor pins. 4. Remove overload protector (3) and discard relay. 5.
SERVICE (CONT.) Compressor Switch Refrigeration Switch Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Remove the cover or splash panel to gain access to the switch. 3. Gently disconnect the wiring harness from the switch. P1684.40 4.
SERVICE (CONT.) Condenser Fan Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Remove the four screws attaching the fan and wire guard to the mounting bracket. 3. Disconnect the 2-pin connector from the fan to the main harness.
SERVICE (CONT.) Removal and Replacement: Control Board, Main 1. Disconnect the dispenser from the power source. 2. Remove the four #6-32 screws securing the control board to the component bracket. 3. Disconnect all the plugs on the main wiring harness from the connectors on the control board.
SERVICE (CONT.) Portion Control Board Removal and Replacement: 1. Remove the five screws securing the door cover to the door frame. 2. Carefully pull the cover forward and disconnect all switch harnesses from the connectors on the control board. 3. Remove the four #6-20 screws securing the control board to the light panel.
SERVICE (CONT.) Circulation Pump Removal and Replacement: 1. Remove dispense platform for ease of taking out recirculating pump. 2. Remove left and right side panels. 3. Remove silicone condensation hose out of bath tank along side recirculating pump. 4. Disconnect pump motor and condenser fan wires (1/4”...
SERVICE (CONT.) Dispense Switch Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Press the locking tabs of the old switch and remove from the mounting bracket. 3. Disconnect the two brown wires and two blue wires from the switch.
SERVICE (CONT.) Dispense Pump 5. Install the new pump tube around the rotor and position into the rear housing with the clamp rest- ing on the top edge. 6. Install the front housing to be flush with the rear housing. 7.
SERVICE (CONT.) Dispense Motor Removal and Replacement: 1. Disconnect the two wires from the dispense mo- tor. 2. Loosen the four #8-32 screws securing the motor to the platform assembly and remove the motor. 3. Inspect the gasket and rubber bushings for signs of wear and replace if necessary.
5. Inspect the o-ring on the manifold tube connector SERVICE (CONT.) for signs of wear and replace if necessary. Dispense Valve 6. Connect the water manifold tube to the valve and secure in place with the plate and #6-32 screw previously removed.
4. Source a magnet to test the switch contacts for SERVICE (CONT.) closure. Dispense Handles 5. With a voltmeter, check across the two terminals for each dispense switch. Place the magnet near the switch surface to close the switch contacts. 6.
SERVICE (CONT.) LED Lamps 4. Check for supply voltage (unregulated +30VDC) across brown wire and white wire at J1 of the regulator board. (FIG 32). If voltge is present as described, replace LED regulator board. If voltage is not present as described, check the wiring back to the main CBA.
SERVICE (CONT.) Indicator LED Removal and Replacement: 1. Disconnect power from the dispenser. 2. Remove the five #6-32 screws securing the door Empty/Low cover to the door. Indicator LED 3. Carefully lower the door cover and disconnect the LED lamp terminals connected to the LED harness. 4.
SERVICE (CONT.) Compressor Relay Removal and Replacement: 1. Disconnect the wires from the relay. 2. Remove the two #8-32 locking screws securing the relay and mounting bracket to the chassis. Remove and discard relay. 3. Install the new relay to the mounting bracket and then on the chassis using two #8-32 locking screws.
SERVICE (CONT.) Water Pump Relay 4. Disconnect and isolate the 120 VAC wires on the relay contact terminals. Check relay contact terminals for continuity when relay coil is activated by the corresponding handle. The meter on the display should show 0.00 or audible tone. If continuity or voltage is not present as described, replace the relay.
SERVICE (CONT.) Program Switch Program Switch Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Remove the cover or splash panel to gain access to the switch. 3. Gently disconnect the wiring harness from the switch. P1684.40 4.
SERVICE (CONT.) Water Inlet Solenoid 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, the solenoid valve may require inspection for wear, and removal of waterborne particles.
SERVICE (CONT.) Water Tank Solenoid Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Turn off the water supply to the dispenser. 3. Remove the two wires from the solenoid valve. 4. Disconnect the water line from the solenoid valve. 5.
SERVICE (CONT.) Water Tank Float Switch Removal and Replacement: 1. Disconnect the dispenser from the power source. 2. Turn off the water supply to the dispenser. 3. Disconnect the float switch from the main harness. 4. Remove the float switch from the tank lid. 5.
SERVICE (CONT.) Temperature Probe Removal and Replacement: (Also known as Water Bath Thermistor) 1. Disconnect the dispenser from the power source. 2. Remove the top rear cover. 3. Disconnect the two pin connector from the dis- penser main wiring harness. 4.
SERVICE (CONT.) Temperature Sensor Removal and Replacement: 1. Remove the left side housing panel. 2. Disconnect the plug on the temperature sensor leads from the connector on the dispenser main harness. 3. Open the cabinet door and remove the product containers.
SERVICE (CONT.) Transformer Removal and Replacement: 1. Loosen the two #8-32 screws securing the com- ponent bracket to the dispenser housing base. 2. Pull component bracket out the front of the dispenser far enough so the transformer can be disconnected from the main wiring harness.
SERVICE (CONT.) Dispense Water Booster Pump Removal and Replacement: 1. Disconnect dispenser from the power source. 2. Shut off nitrogen gas at supply tank. 3. Remove the right side housing panel. 4. Disconnect the plug on the booster pump leads from the connector on the dispenser main harness.
SERVICE (CONT.) Water Pressure Regulator Removal and Replacement: 1. Disconnect dispenser from the power source. 2. Shut off water supply to the dispenser. 3. Remove the right side housing panel. 4. Disconnect the water lines to and from the regulator. 6.
SERVICE (CONT.) Nitrogenator Assembly Water Inlet Check Valve Capillary Tube Nitro Check Valve Outlet Inlet FIG. 57 NITROGENATOR ASSEMBLY Location: FIG. 58 NITROGENATOR ASSEMBLY The Nitrogenator is located inside the cabinet on the Removal and Replacement: platform assembly. The check valves are components 1.
SERVICE (CONT.) Pressure Switch Removal and Replacement: 1. Disconnect dispenser from the power source. 2. Shut off nitrogen supply to the dispenser. 3. Remove the right side housing panel. 4. Disconnect the pressure switch from the Nitrogen line. 5. Install the new pressure switch to the nitrogen line. 6.
SERVICE (CONT.) Nitrogen Regulator Removal and Replacement: 1. Disconnect dispenser from the power source. 2. Shut off water supply to the dispenser. 3. Shut off nitrogen supply to the dispenser. 4. Remove the right side housing panel. 5. Disconnect the water lines and nitrogen supply to the Nitrogenator assembly.
SERVICE (CONT.) Nitro Stout Insert Removal and Replacement: 1. Remove the nitro dispense nozzle. 2. Remove the nitro stout insert from the dispense nozzle. 3. Check for obstructions and clean if necessary. 4. Reinstall the nitro stout insert into the dispense nozzle.
Triac Map 1. Compressor Relay Q25 2. Not Used 3. Not Used 4. Not Used 5. Not Used 6. Not Used 7. Not Used 8. Not Used 9. Not Used Q11 10. Inlet Water Valve Q10 11. Not Used 55124 021418...
Need help?
Do you have a question about the Nitron Cold Draft and is the answer not in the manual?
Questions and answers