Vogt HEC-10, Service Manual

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HEC-Series Service Manual
TROUBLESHOOTING
10/21/01
8-6
Symptom: Motor overload protectors stop machine.
Possible Cause Possible Remedy
Compressor motor overload (CD-OL) stops
machines. NOTE: Overloads are automatic-
reset type, located in junction box of
compressor, Models HEC-30 & HEC-40 only. Motor overloaded due to excessive condensing
pressure or combination of high heat pressure
and low/high voltage check power supply, see
Head Pressure, Section 9. Motor overload due
to a high suction pressure, warm water in water
pan and warm inlet water to condenser during
start-up after a prolonged shutdown period.
Machine should operate satisfactorily after
temperature of water in water pan is reduced
sufficiently so that the suction pressure is less
than 60 psig. Check items under “Freeze-up due
to extended freezing period.” Compressor
binding, or stuck--repair or replace compressor.
Check fuses in disconnect switch. One fuse may
be burnt out resulting in single phasing
compressor motor.
Compressor internal temperature thermal
switch (CD-TS) stops machine. HEC-30 &
HEC-40 will reset automatically after the motor
has cooled sufficiently. The machine can be
manually restarted by pushing the “Start”
button or it will restart automatically after two
hours. Excessive temperature may be caused by gas
leakage between suction and discharge valves of
compressor valve plate. Check for broken valve
plate gaskets or valves. High freezer superheat
or high discharge rpessure can cause excessive
heat.
HEC-10 and HEC-20 have built-in motor
overload and thermal protection with automatic
reset. If compressor shuts off, machine will
continue to run and eventually shut-off on long
freeze cycle, fault #15. See motor overload and internal temperature
thermal switch above for possible remedy.
Cutter motor circuit breaker or pump motor
circuit breaker stops machines. Crushed ice too thick, overloading cutter motor.
Check setting of freezer pressure switch. See
Freezer Pressure Switches, FIGURE 9-1, Section
9. Crushed ice mush, fails to discharge properly,
overloading cutter motor. See Float Valve,
Section 9. Cutter bearing worn in cutter hub,
overload cutter motor. Replace bearing, if
defective. Gear reducer worn or binding,
overloading cutter motor--install gear reducer, if
necessary. Pump fails to rotate due to mineral
build up or foreign materials in impeller housing--
dismantle and clean pump. See Switch Box,
Section 6, FIGURE 6-12. Reset switch, push
“Start” button to restart the machine, and check
motor amps.