Haier DW-86L486, After-Sales Service Manual

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If it not the first time, after the low temperature compressor runs continuously for 5h, it shall be switched
off for 10min. and then run again automatically.
10.9 Voltage Calibration
The operation function of voltage calibration is added on the display panel. In detail, when the display
panel is unlocked, when you press the
key “Clear Alarm” and the key “ ▽ ” for 5s at the same time, the
current voltage deviation is displayed and then you can press “
△
” or “
▽
”to increase or reduce the
voltage. The voltage always goes up or down by 1V and its regulation range is from -9V to 9V. The initial
value of the voltage deviation is 0.
10.10 Setting Adjustment
When power is switched on for the first time, after the display panel is unlocked, if you press “Function
Selection and
“▲” for 5s, the display panel will display -86. Then, if you press “▲” or “▼”, -86, -150, -50,
-40, 380 and 88 will be displayed circularly. If no key is operated in 5s after setting, the display panel will
be locked automatically and the selected value will become valid. After you exit the selected value, the
actual temperature will be displayed again. If you do not select a set value, the default will be -86. After
your selection is valid, the relevant function will be implemented. Besides, the display panel has the
memory function. 88 is an independent backup system.
11. Refrigeration Cycle Prospective and Plan
11.1 Refrigeration Principle
The ultra-low temperature freezer is equipped with a cascade refrigerating system normally composing
of two or more refrigerating systems, i.e. low temperature stage and high temperature stage. For the
high temperature stage, the medium-temperature refrigerant is used; for the low temperature stage, the
low-temperature refrigerant is used. Each part is a complete refrigerating system, a cooling evaporator is
used for linking the two parts together, and it is an evaporator of not only the high temperature stage but
also the low temperature stage. The low temperature refrigerant absorbs heat from the cooled object in
the evaporator of the low temperature system and then transfers the heat to the refrigerant in the high
temperature system through the cooling evaporator, and then the refrigerant in the high temperature
system transfers heat to the cooling medium in the high temperature condenser.
11.2Refrigeration Cycle Prospective and Plan
A -----------Condenser B -----------Dry filter
C -----------
1st stage compressor
D -----------
capillary
E -----------
Gas-liquid separator
F -----------
Heat exchanger
G -----------
Pressure switch
H -----------
Oil separator
A
B
B
D
F
E
G
I
H
J
C
Capillary