Mitsubishi Electric PUHY-200YMF-B Service Handbook page 150

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
(BC) (RC)
3 Indoor
Remote
unit (IC) controller
(RC)
4 Remote
Remote
controller controller
(RC) (RC)
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
BC
transmis-
sion to OC
No reply Same cause of that for grouping from plural re-
(ACK) at frigerants.
RC
transmis-
sion to IC
No reply Trouble of partial IC units:
(ACK) at 1) Same cause as that for single refrigerant
transmis- system.
sion
of SC to IC 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) Slipping off 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) Slipping off 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
transmission
of IC to RC
No reply Trouble of partial IC units:
(ACK) at 1) Same cause of that for single refrigerant sys-
transmis- tem.
sion of
MELANS to Trouble of all IC in one refrigerant system:
RC 1) Error detected by OC unit.
Total capacity error.
Capacity code setting error. (7101)
Connecting number error. (7102)
Address setting error.
2) Slipping off 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) Slipping off or power shutdown of power sup-
ply unit for transmission line.
4) Faulty MELANS.
Cause
(7100)
(7105)
(7100)
(7105)
–148–
Checking method & countermeasure
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.