U-Line U-3090WCWCOL-00, Руководство по обслуживанию

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Troubleshooting
Thermistors
Thermistors are used for various temperature readings. Thermistors
provide reliable temperature readings using a resistance which varies
based on surrounding temperatures. If a faulty thermistor is
suspected it may be tested using an accurate ohmmeter. In an ice
water (0°C / 32°F) resistance should measure 16.1 kilohms,
Thermistor Failure
Zone Thermistors
If a zone thermistor fails, the unit will continue to operate the
zone on a preset time interval of 10 minutes on and 30 minutes
off. The unit will otherwise operate normally. The error will be
displayed on the main display and “Self Test” and logged in “All
Errors”.
Evaporator Thermistors
If an evaporator thermistor fails, the unit will rely on a preset
defrost timer during defrost cycles. The unit will otherwise
operate normally. Evaporator thermistor errors are hidden from
the display and recorded in “All Errors” and displayed in “Self
Test” modes.
Ambient Thermistor
The ambient thermistor is mainly used for diagnostics. If the
thermistor fails, the unit will operate normally.
Reed Switch
A reed switch is used to monitor door state. The switch side for each
zone is mounted under the cabinet and the magnet is mounted to the
cable arm of each respective door. When the door is closed magnetic
force pulls the reed to its contact and closes the circuit which turns
the light and display off. When the door is open the reed pulls away
from the contact and opens the circuit. If the door(s) are left open
for longer than 5 minutes, the switch will trigger an error code and
set an audible warning.
Refrigeration System Diagnosis Guide
Magnet Close To Switch
(Door Closed)
(Switch Closed)
Magnet Away From Switch
(Door Open)
(Switch Open)
System
Condition
Suction
Pressure
Suction
Line
Compressor
Discharge
Condenser Capillary
Tube
Evaporator Wattage
Normal Normal
Slightly below
room
temperature
Very hot Very hot Warm Cold Normal
Overcharge
Higher than
normal
Very cold -
may frost heavily
Slightly warm to
hot
Hot to warm Cool Cold
Higher than
normal
Undercharge
Lower than
normal
Warm -
near room
temperature
Hot Warm Warm
Extremely cold
near inlet - outlet
below room
temperature
Lower than
normal
Partial
Restriction
Somewhat lower
than normal -
in vacuum
Warm -
near room
temperature
Very hot
Top passes warm
lower passes cool
(near room
temperature due
to liquid
Room
temperature
(cool) or colder
Extremely cold
near inlet -outlet
below room
temperature
backing up
Lower than
normal
Complete
Restriction
In deep
vacuum
Room
temperature
(cool)
Room
temperature
(cool)
Room
temperature
(cool)
Room
temperature
(cool)
No refrigeration
Lower than
normal
No Gas
0 PSIG (0 bar)
to 25" (63.5 cm)
vacuum
Room
temperature
(cool)
Cool to hot
Room
temperature
(cool)
Room
temperature
(cool)
No refrigeration
Lower than
normal