Signal Transmission Error On Microcomputer For Humidifying - Daikin FTXZ25NV1B Service Manual

SiMT041311E
2.37 Signal Transmission Error on Microcomputer for
Humidifying
U7
Error Code
Method of Error Communication error between microcomputers mounted on the outdoor unit PCB.
Detection
Error Decision
Conditions
Supposed
Causes
Troubleshooting
Service Diagnosis
The data sent from the microcomputer for humidifying can not be received for 10 seconds.
Zero-cross signal on the microcomputer for humidifying cannot be detected.
Error counter is reset when the data from the microcomputer for humidifying can be
successfully received.
Defective outdoor unit PCB
Noise
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Turn off the power and turn it on
again.
Error again?
YES
Check the varistor (V3, V5) on the
outdoor unit PCB.
Is it broken?
YES
NO
NO
Troubleshooting
The cause can be an
external factor other than
the malfunction.
Observe the operating
condition in long term.
Replace the outdoor unit
PCB.
Replace the varistor.
(R19732)
176