Advertisement
REFRIGERANT CIRCUIT
The hot gas refrigerant discharged from the
compressor reaches the condenser where it is
cooled down and condenses into liquid.
Flowing into the liquid line it passes through the
drier filter, then it goes all the way through the
capillary tube where it loses some of its pressure.
At this time the pressure and temperature are
lowered and the refrigerant enters into the
evaporator coil wrapped around the freezer inner
tube.
The water being constantly fed into the freezer
inner tube exchanges heat with the refrigerant
circulating in the evaporator coil. This causes the
refrigerant to boil-off and it evaporates, thereby
changing from liquid into vapor.
The vapor refrigerant then passes through the
suction accumulator and the suction line where the
refrigerant exchanges heat with the one flowing
into the capillary tube (warmer) before being
sucked into the compressor to be re-circulated.
The refrigerant heat pressure is kept between two
pre-set values 131¸145 psig by the condenser
temperature sensor (the probe is located within the
condenser fins) in air-cooled versions.
When this condenser temperature sensor detects
a rise in condenser temperature (beyond the
pre-fixed limit) it changes its electrical resistance
and sends a low voltage power flow to the
microprocessor on the PC Board that energizes
(through a TRIAC) the Fan Motor in ON-OFF
mode.
When the condenser temperature goes below the
pre-fixed limit, the temperature sensor changes its
electrical resistance again by reducing the flow of
current to the PC Board to cause a temporary stop
of the Fan Motor.
NOTE: If the condenser temperature probe senses
a rise in temperature to 158°F for one of the
following abnormal reasons:
·
CLOGGED CONDENSER
·
FAN MOTOR OUT OF OPERATION
·
AMBIENT TEMPERATURE HIGHER THAN
109.4°F
It will cause the total and immediate SHUT-OFF of
the machine in order to prevent the unit from
operating in abnormal and dangerous conditions.
When the probe stops the ice machine the 2
RED LED will turn on, warning the user of the Hi
Temperature situation. After eliminating the cause
of the increase in temperature, push the RESET
button (PC Board) to restart the ice machine. The
nd
2
RED LED starts blinking and three minutes
later the flaker unit resumes normal operation.
The refrigerant suction or Lo-pressure will be (in
normal ambient conditions about 70°F) about 14.5
PSIG within a few minutes from the unit's start-up.
This value can vary by 1.5 to 2.9 psig in relation to
the water temperature variations influencing the
freezer cylinder.
NOTE: If no ice is made within ten minutes of unit
start up and the evaporating temperature detected
by the evaporator sensor is higher than 30° F the
ice machine stops and the 3rd WARNING
YELLOW LED blinks.
Page 13
GEMD270A
nd
Advertisement
