Mitsubishi Electric PUMY-P112VKM3 Technical & Service Manual page 89

Check code
6607
(A7)
Abnormal points and detection methods
Represents a common error detection
An abnormality detected by the sending side controller when receiving
no ACK from the receiving side, though signal was once sent. The
sending side searches the error in 30 seconds interval for 6 times
continuously.
The cause of displayed address and attribute is on the outdoor unit side
An abnormality detected by the indoor unit if receiving no ACK when
transmitting signal from the indoor unit to the outdoor unit.
The cause of displayed address and attribute is on the indoor unit side
An abnormality detected by the remote controller if receiving no ACK
when sending data from the remote controller to the indoor unit.
The cause of the displayed address and attribute is on the remote
controller side
An abnormality detected by the indoor unit if receiving no ACK when
transmitting signal from the indoor unit to the remote controller.
OCH632A
No ACK error
Causes and check points
The previous address unit does not exist since
the address switch was changed while in electric
continuity status.
Decline of transmission voltage/signal caused by
tolerance over on transmission line
·At the furthest end: 200 m
·On remote controller line: (12 m)
Decline of transmission voltage/signal due to
unmatched transmission line types
·Types for shield line: CVVS, CPEVS, or MVVS
·Line diameter: 1.25 E or more
Decline of transmission voltage/signal due to
excessive number of connected units
Malfunction due to accidental disturbance such as
noise or lightning surge
Defect of error source controller
Contact failure of indoor/outdoor unit transmission
line.
Disconnection of transmission connector (CN2M) on
indoor unit.
Malfunction of sending/receiving circuit on indoor/
outdoor unit.
While operating with multi refrigerant system indoor
units, an abnormality is detected when the indoor
unit transmit signal to the remote controller during
the other refrigerant-system outdoor unit is turned
OFF, or within 2 minutes after it turned back ON.
Contact failure of indoor unit or remote controller
transmission line
Disconnection of transmission connector (CN2M) on
indoor unit
Malfunction of sending/receiving circuit on indoor
unit or remote controller
While operating with multi refrigerant system indoor
units, an abnormality is detected when the indoor
unit transmit signal to the remote controller during
the other refrigerant-system outdoor unit is turned
OFF, or within 2 minutes after it turned back ON.
Contact failure of indoor unit or remote controller
transmission line
Disconnection of transmission connector (CN2M) on
indoor unit
Malfunction of sending/receiving circuit on indoor
unit or remote controller
89
Chart 1 of 4