Mitsubishi Electric PUHZ-ZRP35VKA2 Service Manual page 37

Check Code Abnormal points and detection method
Compressor overcurrent interruption
Abnormal if overcurrent DC bus or com-
pressor is detected after compressor starts
operating for 30 seconds.
UP
(4210)
Remote controller transmission error
(E0)/signal receiving error (E4)
1 Abnormal if main or sub remote control-
ler cannot receive normally any trans-
mission from indoor unit of refrigerant
address "0" for 3 minutes.
(Check code: E0)
2 Abnormal if sub remote controller could
not receive any signal for 2 minutes.
(Check code: E0)
1 Abnormal if indoor controller board can
not receive normally any data from
remote controller board or from other
indoor controller board for 3 minutes.
(Check code: E4)
E0
2 Indoor controller board cannot receive
or
any signal from remote controller for 2
E4
minutes. (Check code: E4)
Remote controller control board
1 Abnormal if data cannot be normally
read from the nonvolatile memory of the
remote controller control board.
(Check code: E1)
2 Abnormal if the clock function of remote
E1
or controller cannot be normally operated.
E2 (Check code: E2)
OCH635A
Cause
1 Stop valve of outdoor unit is closed.
2 Decrease of power supply voltage
3 Looseness, disconnection or con-
verse of compressor wiring connec-
tion
4 Defective fan of indoor/outdoor units
5 Short cycle of indoor/outdoor units
6 Defective input circuit of outdoor
controller board
7 Defective compressor
8 Defective outdoor power circuit board
9 DIP switch setting difference of out-
door controller circuit board
1 Contact failure at transmission wire
of remote controller
2 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.
3 Miswiring of remote controller
4 Defective transmitting receiving cir-
cuit of remote controller
5 Defective transmitting receiving circuit
of indoor controller board of refriger-
ant address "0"
6 Noise has entered into the transmis-
sion wire of remote controller.
1 Defective remote controller
37
Judgment and action
1 Open stop valve.
2 Check facility of power supply.
3 Correct the wiring (U
V W phase) to
• •
compressor. Refer to "10-9. TEST POINT
DIAGRAM". (Outdoor power circuit
board).
4 Check indoor/outdoor fan.
5 Solve short cycle.
6 Replace outdoor controller circuit board.
7 Check compressor. Refer to "10-6. HOW
TO CHECK THE PARTS".
Note: Before the replacement of the outdoor con-
troller 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 volt-
age check with same performing frequency.
8 R eplace outdoor power circuit board
9 Check the DIP switch setting of outdoor
controller circuit board.
1 Check disconnection or looseness
of indoor unit or transmission wire of
remote controller.
2 Set one of the remote controllers "main"
if there is no problem with the action
above.
3 Check wiring of remote controller.
• Total wiring length: max. 500 m
(Do not use cable o 3 or more.)
• The number of connecting indoor units:
max. 16 units
• The number of connecting remote con-
troller: max. 2 units
If the cause of trouble is not any of 1–3
above,
4 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
indoor controller board.
b) When "RC NG" is displayed, replace
remote controller.
c) When "RC E3" or "ERC 00-66" is dis-
played, noise may be causing abnor-
mality.
Note: If the unit is not normal after replacing
indoor controller board in group control,
indoor controller board of address "0" may
be abnormal.
1 Replace remote controller.