AE-X15PU
3 – 1
CHAPTER 3.
FUNCTION AND OPERATION OF PROTECTIVE PROCEDURES
[1] PROTECTION DEVICE FUNCTIONS AND OPERATIONS
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result display
Description
Detection period
Reset condition
Indoor
unit
error
display
Indoor
unit
Outdoor
unit
1
Indoor unit fan lock
Operation stops if there is no
input of rotation pulse signal from
indoor unit fan motor for 1 minute.
When indoor unit fan
is in operation
Operation OFF or ON
I
2
Yes
None
Indoor unit fan rota-
tion speed error
Operation stops if rotation pulse
signal from indoor unit fan indi-
cates abnormally low speed
(about 300 rpm or slower).
When indoor unit fan
is in operation
Operation OFF or ON
I
2
Yes
None
2
2-way valve freeze
prevention
Compressor stops if temperature
of outdoor unit 2-way valve
remains below 0
℃
for 10 continu-
ous minutes during cooling or
dehumidifying operation.
When in cooling or
dehumidifying opera-
tion
Automatic reset when
temperature of 2-way
valve rises above
10
℃
.
None
Yes
Yes
3
Outdoor unit heat
exchanger over-
heat shutdown
Operation frequency lowers if out-
door unit heat exchanger temper-
ature exceeds about 55
℃
during
cooling operation.
Compressor stops if outdoor unit
heat exchanger temperature
exceeds about 55
℃
for 120 sec-
onds at minimum frequency.
When in cooling or
dehumidifying opera-
tion
Automatic reset after
safety period (180
sec).
None
Yes
Yes
4
Compressor dis-
charge overheat
shutdown
Operating frequency lowers if
temperature of compressor
chamber thermistor (TH1) falls
below about 110
℃
.
Compressor stops if temperature
of compressor chamber ther-
mistor (TH1) remains at about
110
℃
(for 120 seconds in cooling
operation, or 60 seconds in heat-
ing operation) at minimum fre-
quency.
When compressor is
in operation
Automatic reset after
safety period (180
sec).
None
Yes
Yes
5
Dehumidifying oper-
ation temporary
stop
Compressor stops if outside air
temperature thermistor is lower
than about 16
℃
during dehumidi-
fying operation.
When in dehumidify-
ing operation
Automatic reset when
outside air tempera-
ture rises above
16
℃
.
None
Yes
Yes
6
DC over current
error
Compressor stops if electric cur-
rent of about 20 A or higher flows
in IPM.
When compressor is
in operation
Operation OFF or ON
Yes
I
1
Yes
Yes
7
AC over current
error
Operating frequency lowers if
compressor AC current exceeds
peak control current value. Com-
pressor stops if compressor AC
current exceeds peak control cur-
rent value at minimum frequency.
When compressor is
in operation
Operation OFF or ON
Yes
I
1
Yes
Yes
8
AC over current
error in compressor
OFF status
Indoor and outdoor units stop if
AC current exceeds about 3 A
while compressor is in non-opera-
tion status.
When compressor is
in non-operation
Replacement of
defective parts such
as IPM
Yes
I
2
Yes
Yes
9
AC maximum cur-
rent error
Compressor stops if compressor
AC current exceeds 17 A.
When compressor is
in operation
Operation OFF or ON
Yes
I
1
Yes
Yes
10
AC current defi-
ciency error
Compressor stops if operating
frequency is 50 Hz or higher and
compressor AC current is about
2.0 A or lower.
When compressor is
in operation
Operation OFF or ON
Yes
I
1
Yes
Yes
*
These models have following thermistors.
The errors for the thermistors that are not mentioned above are irrelevant.
These indoor units don’t have power relay.
INDOOR UNIT
AE-X15PU, AE-X18PU, AE-X24PU
TH1, TH2, TH3, TH4, TH6
