Daikin RMXS-L Series, Руководство по обслуживанию

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Troubleshooting for Outdoor Unit SiUS181305E
223 Troubleshooting
7.33.4 Check for the Factors of Overheat Operation
Check No. 33
Identify the defective points referring to the failure factor analysis (FTA) as follows.
Irregular piping length
Bend/collapse
(Including moisture choke)
Stop valve is closed.
Defective valve coil
Defective valve body
Defective control PCB
←
Check if the voltage property is normal.
←
Does the piping length fall in the permissible range?
←
Conduct visual checks.
←
Remove the moisture by vacuum break.
←
Check if the stop valve is open.
Faulty
discharge
pipe
temperature
control
Faulty hot
gas bypass
control
Hot gas circuit clogging
Defective solenoid
valve coil
Defective solenoid
valve body
Defective control PCB
Defective control
PCB
Defective valve coil
Defective low
pressure sensor
Defective subcooling
heat exchanger
outlet thermistor
Defective valve
body
Faulty
subcooling
electronic
expansion valve
control (Y3E)
Superheat due to
shaft damage
Superheat due to
defective compressor
Faulty control
Outdoor unit
electronic expansion
valve failure
Faulty of 4 way
switch valve
operation
In cooling mode only
(
∗
1)
(
∗
2)
Compressor
overheat
Refrigerant gas
shortage
Large resistance
of piping
Faulty
superheated
degree
control.
When outdoor unit
electronic expansion
valve becomes too
narrow (
∗
3)
Temperature
increase of
discharge
pipe
(R19140)
Subcooling
motor
operated
valve failure
Control
failure
←
Check if coil resistance and insulation
are normal.
←
Check if coil resistance and
insulation are normal.
←
Check if the voltage property is
normal.
←
Check if the connector is connected properly.
Check if the thermistor resistance property
is normal.
←
Check if the pressure value given by the
service checker corresponding to actual
measurement value by the sensor.
←
Check if the piping temperature connected
to the 4 way switch valve is normal.
←
Check if coil resistance and insulation are
normal.
←
Check if the pressure value given by the
service checker corresponding to actual
measurement value by the sensor.
Defective low pressure
sensor
Defective thermistor for
suction pipe
∗
1: Refer to Low Pressure Protection Control for hot gas bypass control.
∗
2: Refer to Electronic Expansion Valve PI Control for subcooling electronic expansion valve control.
∗
3: Superheating temperature control in heating operation is conducted by outdoor unit electronic expansion valve.
(Refer to Electronic Expansion Valve PI Control).
∗
4: Judgment criteria of superheat operation:
(1) Suction gas superheated degree: 10˚C (18˚F) and over.
(2) Discharge gas superheated degree: 45˚C (81˚F) and over, except for immediately after starting and drooping control,
etc..
(Use the above stated values as a guide. Depending on the other conditions, the unit may be normal despite the values
within the above scope.)
←
Check if the connector is connected properly.
Check if the thermistor resistance property is normal.
4 way switch valve is in the
middle position.
Leak from hot gas bypass
valve