Mitsubishi Electric PUHZ-W50VHA-BS Service Manual page 49

Abnormal point and detection method
Error Code
Current sensor error or input current error
· Abnormal if current sensor detects –1.0 A
to 1.0 A during compressor operation.
(This error is ignored during test run.)
UH
·Abnormal if 40 A of input current is detected
or 37 A or more of input current is detected
for 10 seconds continuously. (HW140V only)
Low pressure (63L operated)
Abnormal if 63L is operated (under -0.03
MPa) during compressor operation.
63L: Low-pressure switch
UL
Compressor overcurrent interruption
Abnormal if overcurrent DC bus or
compressor is detected after compressor
starts operating for 30 seconds.
UP
Remote controller transmission error
(E0)/signal receiving error (E4)
Abnormal if main or sub remote controller
cannot receive any transmission
normally from Interface unit/Flow temp.
controller of refrigerant address "0" for 3
minutes.
(Error code: E0)
Abnormal if sub-remote controller could
not receive any signal for 2 minutes.
E0
(Error code: E0)
or
E4
Abnormal if Interface/Flow temp.
controller board can not receive any data
normally from remote controller board or
from other Interface/Flow temp. controller
board for 3 minutes. (Error code: E4)
Interface/Flow temp. controller board
cannot receive any signal from remote
controller for 2 minutes. (Error code: E4)
Remote controller control board
Abnormal if data cannot be read nor-
mally from the nonvolatile memory of the
remote controller control board.
E1
(Error code: E1)
or
E2
Abnormal if the clock function of remote
controller cannot be operated normally.
(Error code: E2)
OCH439H
Case
1 Disconnection of compressor
wiring
2 Defective circuit of current
sensor on outdoor power circuit
board
3 Decrease of power supply
voltage
1 Stop valve of outdoor unit is
closed during operation.
2 Disconnection or loose
connection of connector (63L)
on outdoor controller board
3 Disconnection or loose
connection of 63L
4 Defective outdoor controller
board
5 Leakage or shortage of
refrigerant
6 Malfunction of linear expansion
valve
1 Decrease of power supply voltage
2 Looseness, disconnection or
converse of compressor wiring
connection
3 Defective fan of outdoor units
4 Short cycle of indoor/outdoor
units
5 Defective input circuit of out-
door controller board
6 Defective compressor
7 Decreased water flow
8 Clogged filter of water pipe
9 Clogged plate heat exchanger
0
Locked water pump
1
Malfunction of water pump
Contact failure at transmission
wire of remote controller
All remote controllers are set
as "sub" remote controller. In
this case, E0 is displayed on
remote controller, and E4 is
displayed at LED (LED1, LED2)
on the outdoor controller circuit
board.
Miswiring of remote controller
Defective transmitting receiving
circuit of remote controller
Noise has entered into the
transmission wire of remote
controller.
Defective remote controller
49
Judgment and action
1 Correct the wiring (U
V W phase) to com-
• •
pressor. Refer to 9-6 (Outdoor power circuit
board).
2 Replace outdoor power circuit board.
3 Check the facility of power supply.
1 Check stop valve.
2~4 Turn the power off and on again to check
if F3 is displayed on restarting.
If F3 is displayed, follow the F3 processing
direction.
5 Correct to proper amount of refrigerant.
6 Check linear expansion valve.
Refer to 9-5.
1 Check facility of power supply.
2 Correct the wiring (U
V W phase) to
• •
compressor. Refer to 9-6 (Outdoor power
circuit board).
3 Check outdoor fan.
4 Solve short cycle.
5 Replace outdoor controller circuit board.
6 Check compressor.
Refer to 9-4.
w Before the replacement of the outdoor
controller circuit board, disconnect the wiring
to compressor from the outdoor power circuit
board and check the output voltage among
phases, U, V, W, during test run. No defect
on board if voltage among phases (U-V, V-W
and W-U) is same. Make sure to perform
the voltage check with same performing
frequency.
7~1 Check water circuit and repair the defect.
Check disconnection or looseness of
Interface unit/Flow temp. controller unit or
transmission wire of remote controller.
Set one of the remote controllers "main", If
there is no problem with the action above.
Check wiring of remote controller.
• Total wiring length: max. 500 m
(Do not use cable × 3 or more.)
• The number of connecting remote
controller: max. 2 units
When it is not the above-mentioned problem of
~
Diagnose remote controllers.
a) When "RC OK" is displayed, remote
controllers have no problem.
Turn the power off, and on again to check.
If abnormality generates again, replace
Interface/Flow temp. controller board.
b) When "RC NG" is displayed, replace
remote controller.
c) When "RC E3" or "ERC 00-66" is displayed,
noise may be causing abnormality.
Replace remote controller.