– 199 –
SVSS
valve
Discharge.
Liquid
bypass
capillary,
Check
valve
Clogging
Leakage
O
All cooling
Mainly cooling (Indoor cooling)
Mainly heating (Indoor cooling)
• Operation is changed from heating to cooling.
z
 Indoor unit,
flow selector unit
Check valve
Capillary
clogging
O
Commucation
line
Power
supply line
Disconnection
Contact error
Miswiring
In some cases, phenomena such as above occur.
All cooling (SV11 ON)
Mainly cooling (Indoor cooling)
Mainly heating (Indoor cooling)
O
All heating
Mainly cooling (Indoor heating)
Mainly heating (Indoor heating)
• Gas short is observed and PD and PS may be lower than those
 
in normal time.
• TD and TS may be higher than those in normal time.
All cooling (SV11 ON)
Mainly cooling (Indoor cooling)
Mainly heating (Indoor cooling)
• TCJ and TC1 are heated same as heating. (Heating circuit)
• Suction gas pipe at outdoor side of selector unit is fairly heated.
D
O
All heating
Mainly cooling (Indoor heating)
Mainly heating (Indoor heating)
• Refrigerant i mpact sound is heard at defrost time.
z
 Indoor unit,
flow selector unit
OO
 SVSS circuit
All heating
Mainly cooling (Indoor heating)
Mainly heating (Indoor heating)
• Refrigerant sound may be heard from SVSS valve circuit.
• Temperature of suction gas pipe at outdoor side of the selector
 
unit is higher than that of normal selector unit.
All cooling (SV11 OFF)
O
Check valve
leakage
• Refrigerant sound may be heard from check valve.
• Discharge gas pipe is cold or it may be frozen.
O
 Check valve
circuit
P15
[Gas leak
detection]
Piping
Discharge
pipe Liquid
pipe
Gas pipe
Incorrect
piping
Discharge
pipe ↔
Suction gas
pipe
All cooling (SV11 OFF)
O
• Impossible judgment
All heating
Mainly cooling (Indoor heating)
Mainly heating (Indoor heating)
O
O
• Temperature of suction gas pipe at outdoor side of the FS unit is
 
higher than that of the normal FS unit.
Part name
O
z
Trouble
mode
Operation mode
Phenomenon which appears as result
(Corresponding indoor unit or flow selector unit)
Judgment and position to be checked
Example of
refrigerant
flow
Not
cooled
Not
heated
May become
almost normal
capacity
      Abnormal
refrigerant sound
      Circulating
sound
Detection of
check code