R-290 Compressor - Bunn Ultra NX Service & Repair Manual

SERVICE - RIGHT SIDE PANEL COMPONENTS

R-290 Compressor

FIG. 38 COMPRESSOR 120V
Location:
The compressor is located front center behind the
front panel.
WARNING: Before repair and/or removal of any
refrigeration component must be performed by a
trained and licensed R-290 repair technician.
Right Panel Removal:
1. Loosen 2 right side panel screws on the
underside of the machine.
2. Grab and lower the right panel while pulling the
bottom outward to remove panel.
3. If needed, repeat steps for left side panel.
Test Procedures:
NOTE: A megger is a preferred test over using a
typical ohm meter for testing the compressor windings.
The megger checks the insulation factor of a winding
making sure it is actually insulated and not leaking
current (Ground Fault). An ohm meter usually
produce a low voltage for reading resistance verses
a megger uses higher direct voltage source to
measure insulation resistance to detect a breakdown
in the motor winding insulation.
1. Disconnect main power to the dispenser.
2. Unclip and remove protective cover from
compressor terminals.
3. Access compressor terminal pins and
disconnect the wire leads going to the
compressor pins.
See FIG. 39.
4. Set the megger to the compressor applicable
voltage rating. If the megger you are using only
has a few specific voltage ranges, select the
next highest voltage above your compressor
volt range.
5. Connect one lead of the megger to the copper
suction line or housing. Connect the other lead
to one of the compressor terminal pins (winding).
6. Repeat the procedure for the two remaining
terminal pins. If the instrument indicates any
resistance less than 2 megohms between any
pin and the housing (copper suction line),
120V Compressor Specifications:
Model Number: NE X4170UA
Motor Type: CSCR
Commercial Designation: 1/2 HP
Nominal Voltage & Frequency:
115-127 vac 60 hz, 1 Phase
Evaporating Temperature Range:
-40°F [-40°C] to 32°F [0°C]
Electrical Rating: 9 FLA, 49.50 LRA
Main (run) Winding Resistance:
.96 Ohms @ 77°F [25°C] ±8%
Start Winding Resistance:
3.81 Ohms @ 77°F [25°C] ±8%
Displacement (max): 1.025 in3 [16.80 cm3]
Refrigerant: R-290
Oil Type/Viscosity: Ester/ ISO22
Oil Charge: 11.84 fl. oz. [350 ml.] ±5%
Start
FIG. 39 COMPRESSOR 120V
55
Common
Run
continued >