Mitsubishi Electric PQRY-P200YEM-A Service Handbook page 129

Checking
code
6607 No ACK error
(continued)
System
Generating Display of
compo-
unit address trouble
sition
1 Outdoor Remote
unit (OC) controller
(RC)
2 BC Remote
controller controller
<master> (RC)
(BC)
3 BC Remote
controller controller
<slave> (RC)
(BS)
4 Indoor Remote
unit (IC) controller
(RC)
System
controller
(SC)
5 Remote Remote
controller controller
(RC) (RC)
System
controller
(SC)
Meaning, detecting method
When no ACK signal is detected in 6 continuous times with 30 second
interval by transmission side controller, the transmission side detects error.
Note: The address/attribute shown on remote controller indicates the
controller not providing the answer (ACK).
Detecting
method
No reply As same that for single refrigerant system.
(ACK) at OC
transmis-
sion to BC
No reply As same that for single refrigerant system.
(ACK) at
BC <master>
transmis-
sion to IC
No reply As same that for single refrigerant system.
(ACK) at
BC <slave>
transmission
to BC <master>
No reply Same cause of that for grouping from plural re-
(ACK) at IC frigerants.
transmis-
sion RC
No reply Trouble of partial IC units:
(ACK) at IC 1) Same cause as that for single refrigerant system.
transmis-
sion to SC Trouble of all IC in one refrigerant system:
1) Cause of total capacity error.
2) Cause of capacity code setting error. (7101)
3) Cause of connecting number error. (7102)
4) Cause of address setting error.
5) Disconnection or short circuit of transmission line
of OC unit terminal block for central control (TB7).
6) Power source shut down of OC unit.
7) Trouble of OC unit electrical system.
Trouble of all IC:
1) As same that for single refrigerant system.
2) Insertion of power supply connector (CN40) into
OC unit transmission line for centralized control.
3) Disconnection or power source shut down of
power supply unit for transmission line.
4) Faulty system controller (MELANS).
No reply Same cause as that for plural refrigerant system.
(ACK) at RC
transmission
to IC
No reply Trouble of partial IC units:
(ACK) at 1) Same cause of that for single refrigerant system.
RC
transmis- Trouble of all IC in one refrigerant system:
sion to 1) Error detected by OC unit.
MELANS Total capacity error.
Capacity code setting error. (7101)
Connecting number error. (7102)
Address setting error.
2) Disconnection or short circuit of transmission line
of OC unit terminal block for central control (TB7).
3) Power source shut down of OC unit.
4) Trouble of OC unit electrical system.
Trouble of all IC:
1) As same that for single refrigerant system.
2) Insertion of power supply connector (CN40) into
OC unit transmission line for central-ized control.
3) Disconnection or power shutdown of power
supply unit for transmission line.
4) Faulty MELANS.
Cause
(7100)
(7105)
(7100)
(7105)
–128–
Checking method & countermeasure
Same countermeasure as that for single
refrigerant system.
Same countermeasure as that for single
refrigerant system.
Same countermeasure as that for single
refrigerant system.
Same countermeasure as that for IC unit
error in plural refrigerant system.
→ Same countermeasure as that for
single refrigerant system.
Confirm OC trouble diagnosis LED.
→ At trouble generation, check for the
content according to check code.
Check the content of 5)~7) shown left.
Confirm voltage of transmission line for
centralized control.
• More than 20V → Confirm 1) 2) left.
• Less than 20V → Confirm 3) left.
Same countermeasure as that for plur-
al refrigerant system.
→ Same countermeasure as that for
single refrigerant system.
Confirm OC trouble diagnosis LED.
→ At trouble generation, check for the
content according to check code.
Check the content of 2)~4) shown left.
Check the causes of 1) ~ 4) left.