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Troubleshooting
SiBE811001EB
285
CONVENI-PACK
8.5.25 Check
Check for Causes of Rise in High Pressure
Referring to the Fault Tree Analysis (FTA) shown below, probe the defective points.
CHECK 1
Excessive refrigerant charging
Improper model selection
[In heating]
Stop valve closed
Clogging of foreign particles
Defective valve coil
Defective valve coil
Defective control PCB
Defective valve body
Defective valve body
Defective control PCB
Defective high pressure sensor
Defective high pressure sensor
Short circuit
High outdoor air temperature
Short circuit
High outdoor air temperature
Bent or crashed pipe
Defective suction air thermistor of indoor unit
High suction air temperature of outdoor unit
Defective outdoor air temperature thermistor of outdoor unit
Mixing of non-condensable gas
[In heating]
[In cooling]
Defective valve coil
Defective valve body
Dirty condenser
Rise in high
pressure
Local
pressure
rise
High pipe
resistance
Defective
outdoor unit
electronic
expansion valve
Defective
control
Defective
control
Defective
outdoor unit
solenoid valve
Defective indoor
unit electronic
expansion valve
High suction air
temperature of
indoor unit
High suction air
temperature of
indoor unit
←
Check to be sure the stop valve is
open.
←
Is there any temperature
difference caused before and
after the filter or branch pipe.
←
Conduct visual checks for pipe
conditions.
←
Are the coil resistance and
insulation normal?
←
Are the coil resistance and
insulation normal?
←
Are the electrical characteristics
normal?
←
Are the coil resistance and
insulation normal?
←
Are the electrical characteristics
normal?
←
Is the suction air temperature not
more than 43˚C?
←
Is the outdoor air temperature not
more than 43˚C?
←
Is the suction air temperature not
more than 27˚C?
←
Is the indoor temperature not
more than 27˚C?
←
Is the outdoor air temperature not
more than 16˚CWB?
←
Is the heat exchanger clogged? (In cooling)
←
Is air or else mixed in the refrigerant system?
←
Is the connector properly
connected?
Are the thermistor resistance
characteristics normal?
←
Is the connector properly
connected?
Are the thermistor resistance
characteristics normal?
←
Is the pressure value checked with
the Service Checker
corresponding to the measurement
of the pressure sensor?
←
Is the connector properly
connected?
Are the thermistor resistance
characteristics normal?
←
Is the pressure value checked
with the Service Checker
corresponding to the
measurement of the pressure
sensor?
[In cooling]
If the outdoor unit
electronic expansion
valve is throttled:
(See
∗
1.)
[In heating]
If the indoor unit
electronic expansion
valve is excessively
throttled:
(See
∗
2.)
A temperature difference
in excess of 10˚C between
the inlet and the outlet is
deemed to be abnormal.
Defective high
pressure
control
High
suction air
temperature
of the
condenser
Degradation in
condensing
capacity
Defective indoor unit
liquid pipe thermistor
∗
1: In cooling, the outdoor unit electronic expansion valve (Y1E) and outdoor unit solenoid valve (SV1) are used for “high
pressure control” and “subcooling control”.
∗
2: In heating, the indoor unit electronic expansion valve is used for “subcooling degree control”.