AEX12GRN
3 – 4
2. Outdoor unit
Item Mode Control opera-
tion
When resistance is
low (temperature
judged higher than
actual)
Short-circuit When resistance
is high (tempera-
ture judged lower
than actual)
Open-circuit
Compressor
chamber ther-
mistor (TH1)
Cooling
Dehumidifying
Heating
Expansion valve
control and com-
pressor protection
Compressor oper-
ates, but room does
not become cool or
warm (expansion
valve is open).
Compressor high
temperature error
indication.
Layer short-circuit
or open-circuit may
result in compres-
sor in normal opera-
tion.
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-circuit
error indication.
Normal operation. Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating Expansion valve
control
Defrosting
Defrosting operation
is not activated as
needed, and frost
accumulates on out-
door unit (expansion
valve is closed).
Outdoor unit ther-
mistor short-circuit
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 acti-
vated even if room
temperature is low.
Outdoor unit ther-
mistor short-circuit
error indication.
Heating mode is
activated even if
room temperature is
high.
Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Cooling
Dehumidifying
Operation not
affected
Normal operation. Outdoor unit ther-
mistor short-circuit
error indication.
Normal operation. Outdoor unit ther-
mistor open-cir-
cuit error
indication.
Heating Rating control
Defrosting
Defrosting operation
is activated unneces-
sarily.
Outdoor unit ther-
mistor short-circuit
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 oper-
ates, but room does
not become cool
(expansion valve is
open).
Outdoor unit ther-
mistor short-circuit
error indication.
Frost accumulates
on evaporator 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 oper-
ates, but room does
not become warm
(expansion valve is
open).
Outdoor unit ther-
mistor short-circuit
error indication.
Frost accumulates
on expansion 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 accumulates on
indoor unit evapora-
tor and room does
not become cool
(expansion valve is
closed).
Outdoor unit ther-
mistor short-circuit
error indication.
Compressor oper-
ates, 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-circuit
error indication.
Normal operation. Outdoor unit ther-
mistor open-cir-
cuit error
indication.
To Next Page
Loading...
Need help?
General
