Mitsubishi Electric PUHZ-W50VHA-BS Service Manual page 45

Abnormal point and detection method
Error Code
63H connector open
Abnormal if 63H connector circuit is open
for 3 minutes continuously from being
switched on.
F5
63H: High-pressure switch
2 connector open
Abnormal if both 63H and 63L connector
circuits are open for 3 minutes continuously
from being switched on.
F9
63H: High-pressure switch
63L: Low-pressure switch
Miswiring of Interface unit/Flow temp.
controller-outdoor unit connecting wire
1. Outdoor controller circuit board can
automatically check the number of
connected Interface unit/Flow temp. con-
troller. Abnormal if the number cannot be
checked automatically due to miswiring
of Interface unit/Flow temp. controller-
outdoor unit connecting wire and etc.
EA
after power is turned on for 4 minutes.
2. Abnormal if outdoor controller circuit
board recognizes excessive number of
Interface unit/Flow temp. controller.
Miswiring of Interface unit/Flow temp.
controller-outdoor unit connecting wire
(converse wiring or disconnection)
Outdoor controller circuit board can
automatically set the unit number of
Interface unit/Flow temp. controller.
Abnormal if the Interface unit/Flow
Eb
temp. controller number cannot be
set within 4 minutes after power on
because of miswiring (converse wiring or
disconnection) of Interface unit/Flow temp.
controller-outdoor unit connecting wire.
Start-up time over
The unit cannot finish start-up process
within 4 minutes after power on.
EC
OCH439H
Case
1 Disconnection or contact failure
of 63H connector on outdoor
controller circuit board
2 Disconnection or contact failure
of 63H
3 63H is working due to defective
parts.
4 Defective outdoor controller
circuit board
1 Disconnection or contact failure
of connector (63H,63L) on
outdoor controller circuit board.
2 Disconnection or contact failure
of 63H, 63L
3 63H and 63L are working due
to defective parts.
4 Defective outdoor controller
board.
Contact failure or miswiring
of Interface unit/Flow temp.
controller-outdoor unit
connecting wire
Diameter or length of Interface
unit/Flow temp. controller-
outdoor unit connecting wire is
out of specified capacity.
Excessive number of Interface
unit/Flow temp. controller is
connected to 1 outdoor unit.
(2 units or more)
Defective transmitting receiving
circuit of outdoor controller
circuit board
Defective transmitting receiving
circuit of Interface/Flow temp.
controller board
Noise has entered into power
supply or Interface/Flow
temp. controller-outdoor unit
connecting wire.
Contact failure or miswiring
of Interface unit/Flow temp.
controller-outdoor unit
connecting wire
Diameter or length of Interface
unit/Flow temp. controller-
outdoor unit connecting wire is
out of specified capacity.
Defective transmitting receiving
circuit of outdoor controller
circuit board
Defective transmitting receiving
circuit of Interface/Flow temp.
controller board
Noise has entered into power
supply or Interface unit/Flow
temp. controller-outdoor unit
connecting wire.
Contact failure of Interface unit
/Flow temp. controller-outdoor
unit connecting wire
Diameter or length of Interface
unit/Flow temp. controller-
outdoor unit connecting wire is
out of specified capacity.
Noise has entered into power
supply or Interface unit/Flow
temp. controller-outdoor unit
connecting wire.
45
Judgment and action
1 Check connection of 63H connector on
outdoor controller circuit board.
Refer to 9-6.
2 Check the 63H side of connecting wire.
3 Check for continuity of 63H.
Replace high pressure switch if it is defective.
4 Replace outdoor controller circuit board.
1 Check connection of connector (63H,63L) on
outdoor controller circuit board.
Refer to 9-6.
2 Check the 63H and 63L side of connecting
wire.
3 Check continuity of 63H and 63L.
Replace the pressure switch if it is defective.
4 Replace outdoor controller circuit board.
Check disconnection or looseness or polarity
of Interface unit/Flow temp. controller-outdoor
unit connecting wire of Interface unit/Flow
temp. controller and outdoor units.
Check diameter and length of Interface unit/
Flow temp. controller-outdoor unit connecting
wire.
Total wiring length: 80 m
(Including wiring connecting each Interface
unit/Flow temp. controller unit and between
Interface unit/Flow temp. controller and out-
door unit)
Also check if the connection order of flat
cable is S1, S2, S3.
Check the number of Interface unit/Flow
temp. controller that is connected to 1 out-
door unit. (If EA is detected.)
~ Turn the power off once, and on again to
check.
Replace outdoor controller circuit board
or Interface/Flow temp. controller board if
abnormality occurs again.
Check transmission path, and remove the
cause.
The descriptions above, - , are for EA, Eb
and EC.