Lennox LNWR21X, Руководство по обслуживанию

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Service Manual
Installation and Maintenance
30
4.Fan Motor Can't Operate
Possible Causes Discriminating Method (Air conditioner Status) Troubleshooting
Wrong wire connection, or poor
connection Check the wiring status according to circuit
diagram
Connect wires according to wiring diagram to
make sure all wiring terminals are connected
firmly.
Connection needle stand between
main board and display board is
loose
Check whether the needle stand is loose Insert the needle stand tightly.
Fan capacitor is damaged
1. Discharge the capacitor at first, and then use
universal meter to measure the resistance of fan
capacitor. It displays 0 or very small
2. If the resistance is very big, measure the
voltage at both ends of capacitor. If the voltage
at both ends of capacitor is same with the power
input voltage, the fan capacitor is damaged
Replace fan capacitor.
Power voltage is a little low or
high Use universal meter to measure the power supply
voltage. The voltage is a little high or low
Suggest to equip with voltage regulator .
Motor of outdoor unit is damaged
When unit is on, cooling/heating performance
is bad and ODU compressor generates a lot of
noise and heat.
Change compressor oil and refrigerant. If no
better, replace the compressor with a new one.
5.Compressor Can't Operate
Possible Causes Discriminating Method (Air conditioner Status) Troubleshooting
Wrong wire connection, or poor
connection Check the wiring status according to circuit
diagram
Connect wires according to wiring diagram to
make sure all wiring terminals are connected
firmly.
Compressor relay on main board
is damaged or needle stand of
compressor is loose
Check whether relay can operate normally under
cooling status
Replace the main board with the same model.
Capacitor of compressor is
damaged
1. Discharge the capacitor at first, and then use
universal meter to measure the resistance of fan
capacitor. It displays 0 or very small
2. If the resistance is very big, measure the
voltage at both ends of capacitor. If the voltage
at both ends of capacitor is same with the power
input voltage, the fan capacitor is damaged
Replace the capacitor of compressor.
Power voltage is low or high
After turning on the unit, poor cooling effect or the
compressor is turned on or turned off frequently.
Use universal meter to measure the power
voltage
The fluctuation of the rate voltage is 10%. If the
voltage is low or high, please equip with voltage
regulator.
Coil of compressor is burnt out
Use universal meter to measure the resistance
between compressor terminals and it's 0
Repair or replace compressor.
Cylinder of compressor is blocked Compressor can't operate Repair or replace compressor.
Tube temperature protection
When ambient temperature is high, the detected
temperature by indoor tube temperature sensor
is high. The detected temperature by temperature
sensor at air outlet is also high
Increase the set fan speed. When indoor tube
temperature decreases to a certain value, it will
resume automatically.
Protection of temperature limiter
Check whether the air inlet is blocked by curtains,
clothes, etc. Clean the filter. Move curtains, clothes and other
obstacles.
Malfunction of temperature limiter
When turning on the unit, the heating effect
is poor. Use universal meter to measure the
two contact points of temperature limiter. If the
resistance value is too big, the temperature limiter
is damaged
Replace the temperature limiter.
Thermal fuse is burnt out
When turning on the unit, the heating effect
is poor. Use universal meter to measure the
two contact points of temperature limiter. If the
resistance value is too big, the temperature limiter
is damaged
Replace the thermal fuse.