46
OCH738
Check Code Abnormal points and detection method
Cause
Judgment and action
A7
(6607)
4. If displayed address or attribute is remote
controller, indoor unit detects abnormal-
ity when indoor unit transmits signal to
remote controller and there was no reply
(ACK).
1
During group operation with
indoor unit of multi-refrigerant
system, if indoor unit transmits
signal to remote controller while
outdoor unit power supply of one
refrigerant system is turned off or
within 2 minutes of restart, abnor-
mality is detected.
2
Contact failure of transmission
wire of remote controller or indoor
unit
3
Disconnection of transmission
connector (CN2M) of indoor unit
4
Defective transmitting receiving
circuit of indoor unit or remote
controller
Same as mentioned in “A7” of the previ-
ous page.
5. If displayed address or attribute is FRESH
MASTER, indoor unit detects abnormal-
ity when indoor unit transmits signal to
FRESH MASTER and there was no reply
(ACK).
1
During sequential operation of
indoor unit and FRESH MASTER
of other refrigerant system, if
indoor unit transmits signal to
FRESH MASTER while out-
door unit power supply of same
refrigerant system with FRESH
MASTER is turned off or within 2
minutes of restart, abnormality is
detected.
2
Contact failure of transmission
wire of indoor unit or FRESH
MASTER
3
Disconnection of transmission
connector (CN2M) of indoor unit
or FRESH MASTER
4
Defective transmitting receiving
circuit of indoor unit or FRESH
MASTER
6. If displayed address or attribute is
LOSSNAY, indoor unit detects abnormal-
ity when indoor unit transmits signal to
LOSSNAY and there was no reply (ACK).
1
If the power supply of LOSSNAY
is off, indoor unit detects abnor-
mality when it transmits signal to
LOSSNAY.
2
During sequential operation of
indoor unit and LOSSNAY of
other refrigerant system, if indoor
unit transmits signal to LOSSNAY
while outdoor unit power supply
of same refrigerant system with
LOSSNAY is turned off or within 2
minutes of restart, abnormality is
detected.
3
Contact failure of transmission
wire of indoor unit of LOSSNAY
4
Disconnection of transmission
connector (CN2M) of indoor unit
5
Defective transmitting receiving
circuit of indoor unit or LOSSNAY
7. If displayed address or attribute is nonex-
istent.
1
The unit of former address does
not exist as address switch has
changed while the unit was ener-
gized.
2
Abnormality is detected when
indoor unit transmits signal
because the address of FRESH
MASTER and LOSSNAY are
changed after sequential opera-
tion of FRESH MASTER and
LOSSNAY by remote controller.
