Common fault display freezers, frost frost controller control device failure form mainly has: freezers can't frost, refrigerators refrigeration, ice cream while frost after the compressor cannot be automatically put into operation.
These faults mainly frost heater burn out, timer frost damage, frost caused thermal safety fuse.
Breakdown maintenance maintenance can display freezer frost control device according to the following steps.
With multimeter block measured RX lk frost timer motor dc resistance, normal around 8 kq, such as small resistance value can be measured, there's short circuit fault in the coil, such as large resistance value, there is open circuit fault, the coil frost timer should be replaced.
If the resistance is normal, in the case of wired up, look at the freezer frost timer hand control knob rotating shaft.
If you don't turn, the internal mechanical gears have fault, also want to change the frost timer or removed after repair.
The multimeter R×
L measuring freezers, frost temperature controller, temperature measurements should be infinity, the frost thermostat in the fridge freezer measure should be zero.
If the value is infinite or dozens of Europe, stating that the freezer frost temperature controller is damaged, need to change.
The multimeter R>
L in measuring freezers, frost resistance of the heater, normal for hundreds of Europe.
If measured value is infinite, frost heater has been bad, should also be replaced.
Maintenance example a GR * * card a type 204 e freezers frost light is not bright, heating wire is not hot.
The * * freezer adopts electronic thermostat, the 6.
8 v voltage by resistance R808 and R809 after partial pressure, provides 4 Q802 9 feet.
4 v frost reference voltage.
The freezer temperature sensor is a negative temperature coefficient thermistor.
Before frost, due to the low temperature of the freezer, freezer temperature sensor resistance value is large, the partial pressure on the R810 value is small, Q802 voltage less than 9 feet 8 feet (
14 feet for high level, so the output side, 8 feet to Q801 integrated circuit.
When freezer need frost, presses the button, frost began R119 bottom grounding resistance, Q801 13 feet input low level, the output end of the 11 feet output high level, make the triode Q812 conduction, collector for low level, so the light emitting diode LED01 shine, as freezer frost work lamp.
After electrify measured Q802 8 feet for 6.
8 v, 9 feet of 4.
4 v, 14 feet for OV, visible voltage is greater than 8 feet 9 feet voltage, output for low level 14 feet.
Freezer Sl01 frost buttons when press release again, the output of the Q801 11 feet are still low level, will not make the triode Q812 conduction.
Will take off, freezer freezer sensors measured the resistance value is about 17 kq, put it in my hand, its resistance to reduce rapidly, that sensor normal: then R810 welding, measured their resistance to infinity, that the circuit resistance.