Panasonic U-4LE1R8 Service Manual page 89

3. Mini VRF System Alarm Codes
P29 INV Compressor Start-up Failed (including lock) Due to INV Compressor Wiring
Open Phase, Faulty DCCT, etc.
1. Error Detection Method
•
Abnormal current is detected at DCCT before start-up.
• Start-up failed during overcurrent and/or step-out detected.
• Open-wire of compressor and/or backspin detected.
• Secondary current is not detected during INV compressor is running.
2. Error Diagnosis
1 Wiring
Disconnected parts, miswiring and/or poor connections (loose)
1-1 are observed in the connections of HIC PC board(s) that are
connected by wiring to a compressor. *1
Disconnected parts, miswiring and/or poor connections (loose)
1-2 are observed in the connections of outdoor board(s) that are
connected by wiring from the HIC PC board. *1
2
Disconnections and/or miswiring is observed in the connections
2-1
Compressor
of the compressor terminals. *1
wiring
Conditions such as burned terminal covers and/or discolored
2-2 terminals are observed at the connectors of the compressor
terminals. *1
3 Check the
The results of the pass/fail tests for the following HIC PC board
HIC PC
3-1 IPM show it to be outside the range of the resistance of a
boards
conforming part.
Replace the HIC PC board and operate the unit. (Apply putty
3-2
and screws must not be loose) Does it operate normally?
4 Check the
outdoor
4-1 Replace the control PC board and operate the unit.
control PC
board
*1
Checking for looseness of compressor terminals by wiggling them has the adverse effect of loosening them, so do not do it.
Evaluate them by discoloration of wire insulation near the terminal.
HIC board IPM Pass/Fail Tests
•
Measure with an analog tester. (Set to the k ohm range)
•
Measure the board by itself. (Remove wires connected from other parts.)
• Measure using IPM terminals.
Conforming part resistance value (measure with an analog tester)
Tester terminals
+
-
Resistance value (ohm)
Tester terminals
-
+
Resistance value (ohm)
• Excepting the parts of "
value is "0 = short-circuit".
P
U V
1 k to 5 k 1 k to 5 k 1 k to 5 k
P
U V
100 k to 100 k to 100 k to
100 k to ", it is acceptable if a small resistance value appears as a reference value unless the
W NU U
5 k to 10 k 100 k to
W U
1 k to 5 k
3-49
Mini VRF SYSTEM
Trouble Diagnosis
Correct wiring
Yes
connections
No 1-2
Correct wiring
Yes
connections
No 2-1
Yes Correct
No 2-2
Eliminate looseness
by changing the
Yes
terminals, or crimping
the terminals again.
No 3-1
Yes Replace the HIC board
No 3-2
Yes See what happens.
No 4-1
See what happens.
NU
V W
100 k to 100 k to 100 k to
NU
V W
1 k to 5 k 1 k to 5 k
3
P