Fujitsu AB* A12GATH, Service Manual

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Trouble shooting 23 E42. 3
INDOOR UNIT Error Method:
Indoor unit Heat Ex. outlet temp.
Sensor Error
Indicate or Display:
Indoor Unit : Operation LED 4 times Flash, Timer LED 2 Times Flash,
Filter LED Continuous Flash.
Outdoor Unit : E.5 U.1
Error Code : 4 2
Detective Actuators:
Indoor Unit Controller PCB Circuit
Heat Exchanger Outlet Temp. Sensor
Detective details:
When open or shorted Heat Exchanger outlet temp. sensor is detected
Forecast of Cause :
1. Connector defective connection 2.Sensor defective 3.Controller PCB defective
Check Point 1 : Check connection of Connector
Check if connector is loose or removed
Check erroneous connection
Check if Sensor cable is open
>>Reset Power when reinstalling due to removed connector or incorrect wiring.
OK
Check Point 3 : Check voltage of Controller PCB (DC5.0V)
Corresponding connector
If the voltage does not appear, replace Controller PCB and set up the original address.
Duct type
Cassette type
Wall mounted type
Floor / Ceiling type
Compact Wall mounted type
Heat Ex Outlet temp. Sensor
(Gray Wires)
CN9
Model Type
CN21
04-33
DC
Sensor Characteristics (Rough value)
If Thermistor is either open or shorted, replace it and reset the power.
OK
Check Point 2 : Remove connector and check sensor resistance value
32.4
35
40.0
30
49.8 62.5 79.1 100.9 129.8 168.6
3.03 2.77 2.50 2.22 1.93 1.65 1.39 1.14
25 20 15 10 5 0
Temperature (
95 86 77 68 59 50 41 32
Temperature (
°C)
°F)
17.8 21.6 26.3
3.69 3.49 3.27
50 45 40
122 113 104
Temperature (
Temperature (
°C)
°F)
Voltage Value (V)
Resistance Value (k )
Voltage Value (V)
Resistance Value (k )