Bunn Ultra NX Service & Repair Manual page 48

Left and Right Auger Shaft Assembly
I
DISPLAY
O
TEMP & TORQUE
Left
Torque I
31 - FAN CMP 14 -
O
28° L
Left
Barrel
Temp
Left
Valve
State
I
31 - fan cmp 14
O
"Off"
htr 72°H
Hot
Gas
Temp
FIG. B TORQUE NUMBERS
Small Block (-): Left or Right Refrigerant Solenoid is OFF
Large Block ( ): Left or Right Refrigerant Solenoid is ON
Lower case fan: Means condenser fan is not operating.
Upper case FAN: Means condenser fan is powered and operating.
Lower case cmp: Means compressor is not operating.
Upper case CMP: Means compressor is powered and operating.
Lower case htr: Means the PTC heater is off.
Upper case HTR: Means the PTC heater is on.
The left or right number (currently showing 31 & 14)
is a real time operation number (torque) related to
the Thickness setting which is multiplied by three.
Part Removal and Replacement:
1. Drain, remove and clean hopper; refer to the
Recommended Daily Weekly Cleaning Section
of the Installation & Operating manual, for
proper cleaning procedures.
2. Disconnect the dispenser from the power source.
3. Locate the auger motor 4-pin connector,
push-in the connector tab to release connector
from the machine wiring harness.
NOTE: When removing or installing the motor
be sure the split pin in the motor shaft is turned
to a position that will clear the position sensor
(torque) circuit board.
4. Use a 7/16" nut driver or deep well socket to
remove the 3 nuts securing the auger motor
bracket to the chassis.
5. Grab the auger motor with mounting bracket
and begin pulling motor away from auger shaft
SERVICE - REAR COVER COMPONENTS
Right
Torque
46° R
Right
Barrel
Temp
Right
Valve
htr
State
"On"
being careful that the motor .188 pin clears the
board sensors. Set motor aside.
6. Rotate shaft so the shaft .188 pin clears the
sensor board. Next, pull the auger shaft backward
until the shaft assembly is totally out of the
cooling drum.
7. Before installation of a replacement auger shaft
assembly, absolutely recommended to change
front cooling drum shaft seal and blue bushing.
8. From the front of dispenser, remove the seal and
blue bushing from cooling drum and discard them.
9. Clean seal and bushing surfaces of the cooling
drum very thoroughly. FIG. 28
10. Insert new blue bushing into cooling drum hole.
11. Place seal on insertion tool #37593.00001 or
insert seal by hand with tabs facing outward.
FIG. 28.
12. Push seal into cooling drum hole until it is firmly
seated against the blue bushing; remove tool.
FIG. 28.
13. Place a small amount lubrifilm lubricant on the
ceramic surface area of the replacement auger
shaft before reinstallation. FIG. 27
14. Insert the replacement auger shaft into the rear
of the cooling drum, rotate shaft so pin will clear
torque board sensors and push shaft all the way
in until it passes through the new front seal.
NOTE: Before reinstallation of motor assembly,
ensure a small amount of Krytox grease (M2548.1000)
is present on the torsion spring bearing that will
engage the auger shaft torsion springs.
15. Being carefull, install motor with bracket,
engaging the motor shaft into the auger shaft
torsion springs.
16. Reinstall the 3 nuts that secure the motor
mounting bracket to the chassis.
17. Reconnect the auger motor 4-pin connector to
the machine wiring harness.
Lubrifilm Lubricant
Applied Here
FIG. 27
48
Shaft Seal
Blue Bushing
FIG. 28