Bunn Ultra NX Service & Repair Manual page 58

SERVICE - RIGHT SIDE PANEL COMPONENTS
Compressor Run Capacitor
FIG. 42 RUN CAPACITOR
Location:
The Start and Run Capacitor are located right side,
up front between the start relay and power supply.
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. Front panel will need to be removed to access
the nuts securing capacitors to the machine
frame.
See "Service Front Panel Components" on how
to remove Front Panel.
Test Procedures:
Caution: The Run Capacitor is not required to have
a bleed resistor.
A safe way to discharge a Run Capacitor, take a
20,000 Ohm resistor and connect each end to a
jumper wire with a pair of alligator clips and take the
other end of the alligator clips and connect across
the terminals of the run capacitor. The capacitor
will slowly discharge while monitoring the voltage
across the run capacitor terminals with a multimeter.
Run Capacitor
1. Disconnect main power from the machine.
2. Use Multimeter with Capacitance Setting.
3. Warning: Ensure the start capacitor is
discharged before disconnecting the run
capacitor wires from the machine and remove
run capacitor.
4. Look and take note of the micro Farads rating
on the side of the capacitor.
5. Set multimeter to read capacitance/micro Far-
ads.
6. A non polarized capacitor, connect the multime-
ter leads either way to the capacitor terminals.
NOTE: In case of polarized capacitor, connect
the red probe to the positive terminal of the
capacitor (generally, the longer lead) and the
black probe to the negative terminal (usually,
there will be a marking on the side).
7. The multimeter reading should be within the
rated value on the side of the run capacitor
and/or within the percentage tolerance. Usually
the tolerance is not more than +/- 10%.
9. If the multimeter reading is way far from the
rated value or out of the allowable percentage
range, replace run capacitor.
Run Capacitor Rating:
Ultra NX 120V Models:
RATING: 30 ±5% MFD 420 VAC 50/60HZ
Ultra NX 200-240V Models:
RATING: 12.5 ±5% MFD 420 VAC 50 HZ
FIG. 43 RUN CAPACITOR
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