IVT 12PHR-N - Chapter 3. Function and Operation of Protective Procedures [1] Protection Device Functions and Operations

3-1
12PHR-N
CHAPTER 3. FUNCTION AND OPERATION OF PROTECTIVE PROCEDURES
[1] PROTECTION DEVICE FUNCTIONS AND OPERATIONS
Function Operation Self-diagnosis 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
☆
1
Yes None
Indoor unit fan
rotation speed
error
Operation stops if rotation
pulse signal from indoor unit
fan indicates abnormally low
speed (about 300 rpm or
slower).
When indoor unit fan
is in operation
Operation OFF or ON
☆
1
Yes None
2
Indoor
unit freeze
prevention
Compressor stops if tempera-
ture of indoor heat exchange
pipe thermister remains below
0°C for 4 minutes.
When in cooling
or dehumidifying
operation
Automatic reset
when heat exchanger
temperature
rises above
freeze prevention
temperature(2°C or
higher)
– None None
3
2-way valve
freeze
prevention
Compressor stops if temperat-
ure of outdoor unit 2-way valve
remains below 0°C for 10 con-
tinuous minutes during cooling
or dehumidifying operation.
When in cooling
or dehumidifying
operation
Automatic reset when
temperature of 2-way
valve rises above 10°C.
None Yes Yes
4
Indoor unit
heat exchanger
overheat
shutdown
Operation frequency lowers
if indoor unit heat exchanger
temperature exceeds overheat
temperature during heating
operation.
Compressor stops if indoor unit
heat exchanger temperature
exceeds overheat temperature
for 60 seconds at minimum
frequency.
Overheat temperature
setting value indoor unit
heat exchanger thermistor
temperature: about 45 to 54°C
When in heating
operation
Automatic reset after
safety period (180 sec).
None Yes Yes
5
Outdoor unit
heat exchanger
overheat
shutdown
Operating frequency lowers
if temperature of compressor
chamber thermistor (TH1) falls
below about 110°C.
Compressor stops if temper-
ature of compressor chamber
thermistor (TH1) remains at
about 110°C (for 120 seconds
in cooling operation, or 60
seconds in heating operation)
at minimum frequency.
When in cooling
or dehumidifying
operation
Automatic reset after
safety period (180 sec).
None Yes Yes
6
Compressor
dischange
overheat
shutdown
Operating frequency lowers
if temperature of compressor
chamber thermistor (TH1)
falls below about 110°C.
Compressor stops if
temperature of compressor
chamber thermistor (TH1)
remains at about 110°C
(for 120 seconds in cooling
operation, or 60 seconds in
heating operation) at minimum
frequency.
When compressor is
in operation
Automatic reset after
safety period (180 sec).
None Yes Yes
7
Dehumidifying
operation
temporary stop
Compressor stops if outside air
temperature thermistor is lower
than about 16°C during dehu-
midifying operation.
When in
dehumidifying
operation
Automatic reset when
outside air temperature
rises above 16°C.
None Yes Yes
12PHR-N_S530612PHRN.indd 1 2013/8/7 15:42:14