Check For Causes Of Drop In Low Pressure - Daikin VRVII Manual

CHECK 2
Referring to the Fault Tree Analysis (FTA) shown below,
probe the defective points.
[In cooling]
Defective low
pressure
control
[In both
cooling and
heating]
(∗2.)
[In cooling]
Abnormally
If the indoor
dropping low
unit electronic
pressure
expansion
(Low
valve is
evaporating
throttled too
temperature)
much:
(∗3.)
Defective
electronic
expansion
valve control
[In heating]
If the outdoor
unit electronic
expansion
valve
excessively
throttled:
(∗4.)
A
348
Troubleshooting by Indication on the Remote Controller
Check for causes of drop in low
pressure
Defective
compressor
(∗1.)
capacity
control
Defective low
pressure
protection
control
Defective
indoor unit
electronic
expansion
valve
Defective
control
Defective
outdoor unit
electronic
expansion
valve
Defective
control
← Are the electrical
Defective low
pressure characteristics normal?
sensor
← Is the pressure value
Defective
service checked with the Service
monitor PCB Checker corresponding to
the measurement value of
the pressure sensor?
← Are the electrical
Defective low
pressure
characteristics normal?
sensor
Defective hot
← Are the coil resistance and
gas solenoid
insulation normal?
valve
← Is the pressure value
Defective
service
checked with the Service
monitor PCB
Checker corresponding to
the measurement value of
the pressure sensor?
← Are the coil resistance and
Defective
valve coil
insulation normal?
Defective
valve body
← Check for the thermistor
Defective gas
pipe thermistor
resistance and connection.
of indoor unit
← Check for the thermistor
Defective liquid
pipe thermistor
resistance and connection.
of indoor unit
← Is the pressure value
Defective
service
checked with the Service
monitor PCB
Checker corresponding to
the measurement value of
the pressure sensor?
← Are the coil resistance and
Defective
valve coil
insulation normal?
Defective
valve body
← Are the electrical
Defective low
pressure
characteristics normal?
sensor
← Check for the thermistor
Defective
suction pipe
resistance and connection.
thermistor
Defective
service
monitor PCB