Mitsubishi Electric PUZ-HA24NHA1, Service Manual

Page: 48 / 128

48
OCH750A
• Before repair
Frequent calls from customers
1
The operating display of remote
controller does not come on.
Phone Calls From Customers How to Respond Note
1
Check if power is supplied to air conditioner.
Nothing appears on the display unless power is
supplied.
2
Unit cannot be restarted for a
while after it’s stopped.
2
Wait around 3 minutes to restart unit.
The air conditioner is in a state of being protected
by the microprocessor’s directive. Once the
compressor is stopped, the unit cannot be
restarted for 3 minutes. This control is also applied
when the unit is turned on and off by remote
controller.
3
Check code appears and blinks
on the display of remote
controller.
Refer to “SELF-DIAGNOSIS
ACTION TABLE”.
Check if servicing is
required for the error.
Display time of “ ”
depends on the model.
Long life filter: 2500 h.
Standard filter: 100 h.
3
Check code will be displayed if any protection
devices of the air conditioner are actuated.
What is check code?
1
“Please Wait” is displayed
on the screen.
1
Wait around 2 minutes.
An automatic startup test will be conducted for
2 minutes when power is supplied to the air
conditioner. “Please Wait” will be kept displayed
while that time.
2
“ ” is displayed on the
screen.
2
This indicates that it is time to clean the air filters.
Clean the air filters. “ ” can be cleared from
the filter information of the maintenace menu.
See the operation manual that came with the
product for how to clean the filters.
3
“Heat Standby” is displayed on
the screen.
3
This is displayed when the unit starts HEAT
operation, when the thermostat puts the
compressor in operation mode, or when the
outdoor unit ends DEFROST operation and
returns to HEAT operation.
The display will automatically disappear around
10 minutes later.
While “Heat Standby” is displayed on the remote
controller, the airflow amount will be restricted
because the indoor unit’s heat exchanger is not
fully heated up. In addition to that, the up/down
vane will be automatically set to horizontal blow
in order to prevent cold air from directly blowing
out to human body. The up/down vane will return
to the setting specified by the remote controller
when “Heat Standby” is released.
4
“Heat Defrost” is displayed on
the screen. (No air comes out of
the unit.)
4
The outdoor unit gets frosted when the outside
temperature is low and the humidity is high.
“Heat Defrost” indicates the DEFROST
operation is being performed to melt this frost. The
DEFROST operation ends in around 10 minutes
(at most 15 minutes).
During the DEFROST operation, the indoor unit’s
heat exchanger becomes cold, so the fan is
stopped. The up/down vane will be automatically
set to horizontal blow in order to prevent cold air
from directly blowing out to human body. The
display will turn into “Heat Standby” when
DEFROST operation ends.
Unit does
not operate
at all.
Remote
controller