Name
OH thermistor A
OH thermistor B
D F thermistor A
D F thermistor B
Outdoor temperature
thermistor A
lectric expansion valve
thermistor (thin pipe 1) A
lectric expansion valve
thermistor (thick pipe 1) A
lectric expansion valve
thermistor (thin pipe 2) A
lectric expansion valve
thermistor (thick pipe 2) A
lectric expansion valve
thermistor (thin pipe 1) B
lectric expansion valve
thermistor (thick pipe 1) B
lectric expansion valve
thermistor (thin pipe 2) B
lectric expansion valve
thermistor (thick pipe 2) B
Table 6-2 shows the correspondence between
●
the thermistorÕs resistance and the temperature.
They should be used as reference values. The
value, which you measure, may be slightly
difference from that in the table. It depends on
the instrument.
When you measure the resistance, pull out the
●
connector after turning off the power supply.
Pulling out the connector while the power supply
is turned on will cause troubles.
Avoid measuring the voltage at the HIC pins.
●
However if you must measure it, be aware that
the basic voltage potentials at HIC pins should
be 0V-A in A cycle and 0V-B in B cycle. The
voltage may be measured incorrectly when the
basic voltage potential is wrong.
All manuals and user guides at all-guides.com
Table 6-1 Name and Role of each thermistor
Connector No
Measuring Point
CN4A
A cycle compressor head
CN4B
B cycle compressor head
CN5A
A cycle heat exchanger
CN5B
B cycle heat exchanger
CN6A
Outside temperature
CN7A
Indoor unit 1 (thin pipe)
Indoor unit 1 (thick pipe)
Indoor unit 2 (thin pipe)
Indoor unit 2 (thick pipe)
CN7B
Indoor unit 3 (thin pipe)
Indoor unit 3 (thick pipe)
Indoor unit 4 (thin pipe)
Indoor unit 4 (thick pipe)
Table 6-2 Correspondence between each thermistorÕs
resistance and temperature (reference value)
lectric expansion valve
thermistor
D F thermistor
Outdoor temperature
thermistor
OH thermistor
- 304 -
Role
If the temperature of the compressor
rises abnormally (118¡C), the
compressor will be stopped. The
temperature is used to decide the
operation of the valve.
The thermistors decide the defrost
operation during heating combined
the data of the outside temperature
and its data.
Outdoor temperature is used to
decide the various operations of the
air conditioner.
The thermistors detect the
temperatures of the piping to the
indoor units. The temperatures are
used to decide how much the
expansion valve is opened.
Temperature Resistance
-15¡C
12.6k
Ω
0¡C
6.1k
Ω
25¡C
2.2k
Ω
50¡C
860
Ω
75¡C
400
Ω
Temperature Resistance
-15¡C
12.6k
Ω
0¡C
6.1k
Ω
15¡C
3.2k
Ω
30¡C
2k
Ω
Temperature Resistance
25¡C
33.9k
Ω
50¡C
10.8k
Ω
75¡C
4.1k
Ω
100¡C
1.7k
Ω
105¡C
1.5k
Ω
118¡C
1k
Ω
HIC pin
potential
1.0V
1.7V
3.0V
3.9V
4.4V
Potential
1.0V
1.7V
2.4V
3.1V
Potential
0.5V
1.3V
2.4V
3.4V
3.6V
3.9V