Lektro-Vend Combo Series, Руководство по обслуживанию

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REFRIGERATION SYSTEM OPERATION
general cycle described 41 occurs within the refrigeration system fitted in Polyvend equipment.
The following is a detailed explanation of the function of the various components in the system.
As the temperature within the cabinet increases, the liquid contained in the temperature control feeler bulb
(thermostat sensor) also rises in temperature, and in doing so, expands. This expansion increases the
pressure against the temperature control bellows, and actuates the temperature control switch. This switch
applies power to the compressor and the condenser fan motor. The condenser fan pulls air through the
condenser coil, removing the heat from the refrigerant vapor from inside the coils. The compressor pulls low
pressure refrigerant vapor from the evaporator and compresses it, increasing both its temperature and
pressure. This high-temperature/pressure vapor is expelled to the condenser, where the vapor sheds its
excess heat, as drawn off by the airflow, through the condenserfins, created by the condenser
fan.
The cooled
gas in the condenser turns into a liquid, which is pumped via pressure from the compressor through the drier,
which removes any water and particles from the liquid refrigerant. This liquid is then forced through the
expansion valve, which acts like a throttle for the system, controlling the flow rate of the liquid refrigerant into
the evaporator. Airflow is circulated throughout the cabinet by the evaporator fan, which pulls airflow through
the coils and fins of the evaporator. Any excess heat present in the airflow is drawn off by the liquid refrigerant,
which evaporates, and is in turn, pulled via the compressor through the accumulator, which traps and allows
for the evaporation of any liquid refrigerant leaving the evaporator. The vapor is pulled down in the suction
line to the compressor. The falling temperature in the cabinet eventually cools the liquid in the temperature
control feeler bulb, condensing the liquid inside, reducing its pressure, which releases the pressure against
the temperature-control bellows.
This reduction deactivates the switch inside, cutting off power to the
compressor and condenser-fan motor.
SYSTEM SETUP AND ADJUSTMENT
The refrigerated side of the Polyvend Combo machine is regulated by the temperature control, located in the
bottom of the machine on the right hand side on the front of the cabinet of the modularcooling unit. The cooling
unit is not set from the factory for the temperature to run from between 36 and 38 degrees, so adjustment is
normally required. Should you need to adjust the thermostat, allow the unit to cool down ofr one hour and then
make only small adjustments approximately
of a turn at a time of a turn is 2 degrees of temperature
change). To adjust the unit colder turn the slotted screw clockwise of a turn. To adjust the unit so that it
is warmer turn the slotted screw counter clockwise of a turn and wait for the unit to balance out (about
45 minutes).’
Check that the condenser and evaporator fans run freely and do not make excessive noise, which might
indicate an obstruction to the fan blade. Check to make sure that the door gasket is sealing to the cabinet.
NOTE: Make sure that the thermostat control feeler bulb is positioned in the air flow from the evaporator and
not resting against any metal surfaces causing a false reading. Should be mounted in the plastic clip in the
rear wall area behind the carousel.