Troubleshooting; Inverter Heat Pump - Mitsubishi Electric M Series Manual

M series
C.2.8 TROUBLESHOOTING
C.2.8.1 Inverter Heat Pump
MFZ-KA25VA MFZ-KA35VA MFZ-KA50VA
Failure mode recall function
Outline of the function
This air conditioner can memorize the abnormal condition which has occurred once.
Even though OPERATION INDICATOR lamp indication listed on the troubleshooting check table disappears, the memo-
rized failure details can be recalled.
This mode is very useful when the unit needs to be repaired for the abnormality which does not recur.
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
The cause of abnormality cannot be found because the abnormality does not recur.
Setting up the failure mode recall function
Turn ON the power supply.
While pressing both OPERATION SELECT
button and TOO COOL button on the remote controller at the same
time, press RESET button.
First, release RESET button.
And release the other two buttons after all LCD except the set
temperature in operation display section of the remote controller is
displayed after 3 seconds.
Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature
is displayed) with the remote controller headed towards the indoor unit.
Does the left lamp of OPERATION INDICATOR lamp
on the indoor unit blink at the interval of 0.5 seconds?
Blinks: Either indoor or outdoor unit is abnormal.
Beep are emitted at the same timing
as the blinking of the left lamp of
OPERATION INDICATOR lamp.
Judgment of indoor/outdoor abnormality
Before blinking, does the left lamp of OPERATION
INDICATOR lamp stay ON for 3 seconds?
Stays ON for 3 seconds (without beep):
The outdoor unit is abnormal.
The indoor unit is abnormal.
Check the blinking pattern, and confirm the
abnormal point with the indoor unit failure mode table.
Make sure to check at least two consecutive blinking cycles.
Releasing the failure mode recall function
Release the failure mode recall function by the following procedures.
Turn OFF the power supply and turn it ON again.
Press RESET button of the remote controller.
Repair the defective parts.
Deleting the abnormal
memorized condition
After repairing the unit, recall the failure mode again according to "Setting up the failure
mode recall function" mentioned above.
Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is
displayed) with the remote controller headed towards the indoor unit.
Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
Release the failure mode recall function according to "Releasing the failure mode recall
function" mentioned above.
Note1.Make sure to release the failure mode recall function once it is set up, otherwise the unit cannot operate properly.
2.If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.
2. Blinking pattern when the indoor unit is abnormal:
Blinking at 0.5-
2.5-second OFF second interval
ON
OFF
Beeps
Repeated cycle
3.Blinking pattern when the outdoor unit is abnormal:
2.5-second OFF 3-second ON
ON
OFF
2
Yes
(Blinks)
No
2
Blinking at 0.5-
2.5-second OFF second interval
Beeps
Repeated cycle
Blinking at 0.5-
second interval 2.5-second OFF
No beep Beeps
Repeated cycle
FLOOR-STANDING Inverter Heat Pump
1
No Indoor unit is normal.
But the outdoor unit might be abnormal because there are some
(OFF)
abnormalities that are not memorized in the indoor unit.
Confirm if outdoor unit is abnormal according to the flow chart of the
detailed outdoor unit failure mode recall function.
Yes
The outdoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point.
Make sure to check at least two consecutive blinking cycles.
As for outdoor unit, refer to outdoor unit service manual.
1
Beeps
Repeated cycle
Blinking at 0.5-
second interval
3-second ON
No beep
Repeated cycle
While pressing both OPERATION SELECT
button and TOO COOL button on the remote
controller at the same time, press RESET button.
First, release RESET button.
And release the other two buttons after all LCD
except the set temperature in operation display
section of the remote controller is displayed after
3 seconds.
1. Regardless of normal or abnormal, a short
beep is emitted once as the signal is received.
3
Beeps
Repeated cycle
C-257