Sunbeam 20060328, Руководство по обслуживанию

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COMPRESSOR MOTOR ELECTRIC CHECKING
When checking electric problems, always make sure there is an electric circuit to the cabinet, and the temperature-
selecting dial is not in the “OFF” position (switched off).
When the shielded unit doesn’t start, the problem can be found in the relay, the protector, the thermostat, the wire or the
compressor motor itself.
If the compressor doesn’t work, test the voltage through the relay and overload protector electric conductor terminals.
(See the wire diagrams*).
The voltimeter must show the line voltage if the thermostat knob is in position of normal operation instead of the “OFF”
position. If this test doesn’t show an active circuit, it is necessary to check if there is an open circuit in the thermostat and
the wired. Pay attention to all the terminal connections.
The control thermostat can be verified using a piece of wire as a temporary bridge through the two thermostat terminals.
If the compressor starts this way and works with the bridge, then the control thermostat is damaged and must be
replaced.
If the voltage verification shows energy feeding in the relay terminals, check the compressor by using manual test
equipment.
If the compressor motor doesn’t start nor works with the test equipment or the normal electric accessories, verify the line
voltage and make sure there is no more than 10% variation with respect to the nominal voltage. If the voltage is
adequate and the compressor doesn’t start nor functions, change the compressor.
If the compressor starts and works with the test equipment, change the relay.
ELECTROMECHANIC THERMOSTATS FOR TEMPERATURE CONTROL
.
The thermostats are the devices allowing the refrigerator temperature adjustments, thanks to the mechanic internal
components propeled by the answer of a refrigerant contained in the sensor bulb, which regulates the operation of the
remaining electric components in the refrigeration system (compressor, resistances, timers, etc.).
The sensor bulb is located in appropriate points of the evaporating system or the compartment environment to obtain a
response in agreement with the temperature requirements of the refrigerator general environment.
The control knob rotation has three zones of temperature adjustment for the refrigerator’s internal environment as per its
rotation, that is, first third (SWITCHED OFF or 0 to 3) includes COLD temperatures, second third (3 to 5) the COLDEST
temperatures and the 3rd. third part (5 to 7) the VERY COLD temperatures.
These are the thermostats used in the different models of refrigerators:
Semi - automatic Defrosting / Manual Models (Push Button – Constant Differential and Constant Cut
off: Figure B7-A)
They are used in the one door cyclic models and for any position of the knob (from 1 to 7) the temperature difference
evaluated between compressor stop and start is the same. By pressing the defrosting button, this design is capable of
interrupting the thermostat operating cycle in any moment to defrost the evaporator and re – start automatically the cycle
operation once it r5±1°C, without switching off the control (position 0). The bulb is located in the internal zone of
the freezer right wall.
Automatic / manual defrost models (plate heating – Variable Differential and Constant Cut off: Figure
B7-B)
They are used in the two doors models with cooler plate, the cyclic models and the frost-free models (conventional and
tropicalized models)
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