VendNet CB500-SA - Compressor Troubleshooting and Performance; Compressor Start-Up Failures; Compressor Overload Tripping; Addressing Unit Noise and Vibration

12 | 3578 • CB500 VENDOR
COMPRESSOR WILL NOT START
A. Vendor not plugged in.
B. Tripped breaker or blown fuse.
C. Faulty wall outlet.
D. Short or tear in power cord.
E. Improper wiring.
F. Low voltage: 5 % below. Check the
power source with the Multi-Meter.
G. Overload defective: Trips too
fast. Check overload with the
Multi-Meter.
H. Start relay defective: Check start
relay with the Multi-Meter.
I. Compressor has open windings.
Check compressor windings with
a Multi-Meter.
J. Defective thermistor.
COMPRESSOR TRIPS ON OVERLOAD
A. Improper voltage: 5-10% above,
5% below. Check power source
with Multi- Meter.
B. Overload defective: Trips too fast.
Check overload with Multi-Meter.
C. Relay defective: Won't open after
starting. Check relay with Multi-
Meter.
D. Compressor has shorted windings:
Check compressor windings with
Multi-Meter.
E. Short in another component:
Isolate and eliminate each
electrical component until short
is found.
F. Compressor is too hot.
• Dirty condenser.
• Faulty condenser motor or
blade.
• Restricted airflow.
CAUTION: Condenser must be kept clean of dirt and debris to
allow for proper air circulation.
NOISY OR VIBRATING UNIT
A. Components rubbing or touching
each other.
• Check fan blades and motor.
• Loose shrouds and harness.
• Copper tubing.
• Loose or unsecured parts.
B. Worn or aged grommets.
• Compressor
• Bad valves.
• Slugging.
• Bad windings (see Figure
12).
• Low voltage.
UNIT SHORT CYCLES
• Temperature setting set too warm. See Refrigeration Controls section
above.
UNIT OPERATES LONG OR CONTINUOUSLY
A. Air flow restricted
• Faulty evaporator motor or
blades causing coils to ice over.
• Loose connections on
evaporator motor. (One motor
not running.)
B. Gasket leak around main door.
C. Gasket leak around delivery
door.
D. Excessive load: After loading,
unit will run longer to pull out
excessive heat from product.