Heat Ex.2 Liquid Temp. Sensor - Fujitsu Airstage VR-II Series Service Manual

Trouble shooting 40
OUTDOOR UNIT Error Method:
Heat Ex.2 Liquid Temp
Sensor Error
Detective Actuators:

Heat ex.2 liquid temp. sensor

Forecast of Cause :
1. Connector connection defective, open
2. Sensor defective
3. Main PCB defective
Check Point 1 : Check the connector connection and cable open
Connector connection state check
Cable open check
OK
Check Point 2: Check the sensor
Sensor characteristics check (Disconnect the sensor from the PCB and check.)
* For the sensor characteristics, refer to the "Service Parts Information 25".
OK
Check Point 3 : Check voltage of Main PCB (DC5.0V)
Main PCB (CN164: 1-2) voltage value = 5V
Remove the sensor from Main PCB, check the voltage.
THERMISTOR (HEX. LIQ.2)
BLACK
1 1
BLACK
2 2
BLACK
3 3
CN164
BLACK
4 4
THERMISTOR (HEX. GAS.2)
5 5
6 6
7 7
Heat ex.2 liquid temp. sensor (CN164: 1-2)
If the voltage does not appear, replace Main PCB and set up original address
Indicate or Display:
E73. 7
Outdoor Unit : E. 7 3. 7
Indoor Unit
Error Code
Detective details:
Heat ex.2 liquid temp. sensor short or open detected
: Operation LED 9 times Flash, Timer LED 15 Times Flash,
Filter LED Continuous Flash.
: 9 U / 7 3
DC
04-49