Daikin FTX20K2V1B, Service Manual

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Check SiBE041525F
85 Service Diagnosis
5.8 Rotation Pulse Check on the Outdoor Unit PCB
Check No.16
Make sure that the voltage of 320 + 100 V ~ 320 - 50 V is applied.
1. Set operation off and power off. Disconnect the connector S70 or S71.
2. Check that the voltage between the pins 4 - 7 is 320 VDC.
3. Check that the control voltage between the pins 3 - 4 is 15 VDC.
4. Check that the rotation command voltage between the pins 2 - 4 is 0 ~ 6.5 VDC.
5. Keep operation off and power off. Connect the connector S70 or S71.
6. Check whether 4 rotation pulses (0 ~ 15 VDC) are input at the pins 1 - 4 when the fan motor
is rotated 1 turn by hand.
When the fuse is melted, check the outdoor fan motor for proper function.
If NG in step 2 → Defective PCB → Replace the outdoor unit PCB (main PCB).
If NG in step 4 → Defective Hall IC → Replace the outdoor fan motor.
If OK in both steps 2 and 4 → Replace the outdoor unit PCB (main PCB).
1
2
3
4
5
6
7 320 VDC
(R20507)
S70 or S71
PCB
Actual rotation pulse input (0 ~ 15 VDC)
Rotation command voltage (0 ~ 6.5 VDC)
Control voltage 15 VDC