AYXP12JHRN
3 – 4
2. Outdoor unit
Item
Mode
Control opera-
tion
When resis-
tance is low
(temperature
judged higher
than actual)
Short-circuit
When resis-
tance is high
(temperature
judged lower
than actual)
Open-circuit
Compressor
chamber ther-
mistor (TH1)
Cooling
Dehumidifying
Heating
Expansion valve
control and com-
pressor protection
Compressor
operates, but
room does not
become cool or
warm (expansion
valve is open).
Compressor high
temperature error
indication.
Layer short-cir-
cuit or open-cir-
cuit may result in
compressor in
normal operation.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heat exchanger
thermistor (TH2)
Cooling
Dehumidifying
Outdoor unit heat
exchanger over-
heat prevention
Compressor
operates at low
speed or stops.
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Normal operation.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating
Expansion valve
control
Defrosting
Defrosting opera-
tion is not acti-
vated as needed,
and frost accumu-
lates on outdoor
unit (expansion
valve is closed).
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Defrosting opera-
tion is activated
unnecessarily,
and room does
not become warm
(expansion valve
is open).
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Outside air tem-
perature ther-
mistor (TH3)
Auto
Operation mode
judgment
Cooling mode is
activated even if
room tempera-
ture is low.
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Heating mode is
activated even if
room tempera-
ture is high.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Cooling
Dehumidifying
Operation not
affected
Normal operation.
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Normal operation.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating
Rating control
Defrosting
Defrosting opera-
tion is activated
unnecessarily.
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Defrosting opera-
tion is not acti-
vated, and frost
accumulates on
outdoor unit.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Suction pipe ther-
mistor (TH4)
Cooling
Dehumidifying
Expansion valve
control
Compressor
operates, but
room does not
become cool
(expansion valve
is open).
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Frost accumu-
lates on evapora-
tor inlet section,
and room does
not become cool
(expansion valve
is closed).
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating
Expansion valve
control
Compressor
operates, but
room does not
become warm
(expansion valve
is open).
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Frost accumu-
lates on expan-
sion valve outlet
section, and room
does not become
warm (expansion
valve is closed).
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
2-way valve ther-
mistor (TH5)
Cooling
Dehumidifying
Expansion valve
control
Frost accumu-
lates on indoor
unit evaporator
and room does
not become cool
(expansion valve
is closed).
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Compressor
operates, but
room does not
become cool
(expansion valve
is open).
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating
Operation not
affected
Normal operation.
Outdoor unit ther-
mistor short-cir-
cuit error
indication.
Normal operation.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
