Fujitsu AOUH18LPAS1, Service Manual

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Check point 3. Check the solenoid coil and 4-way valve
• Solenoid coil
Remove CN30 from PCB and check the resistance value of coil. Resistance value is about 1.88
kΩ — 2.29 kΩ (at 68 °F [20 °C]).
→ If it is open or abnormal resistance value, replace solenoid coil.
• 4-way valve
Check each piping temperature, and the location of the valve by the temperature difference.
If the value location is not proper, replace 4-way valve.
↓
Check point 4. Check the voltage of 4-way valve
Check the voltage CN30 of Main PCB.
→ Check if AC 187 V (AC 208 V -10%) to AC 253 V (AC 230 V +10%) appears at CN30 of Main
PCB.
• Heating operation
→ If it is not voltage, Replace Main PCB.
• Cooling operation
→ If it is voltage, Replace Main PCB.
↓
Check point 5. Replace main PCB
If Check Point 1 to 4 do not improve the symptom, replace main PCB.
↓
End
2-23. E: 99. 4-way valve error (Outdoor unit)
- (03-29) -
2. Troubleshooting with error code
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