6-10 The Following Symptoms Are Normal - Mitsubishi Electric PURY-HP72 Service Handbook

Hide thumbs Also See for PURY-HP72:
Table of Contents


[6-10 The Following Symptoms Are Normal ]

6-10 The Following Symptoms Are Normal

The indoor unit does not start
after starting cooling (heating)
The auto vane adjusts its posi-
tion by itself.
The fan speed changes dur-
ing heating.
The fan stops during heating
The fan keeps running after
the unit has stopped.
The fan speed does not reach
the set speed when operation
switch is turned on.
When the main power is
turned on, the display shown
on the right appears on the in-
door unit remote controller for
5 minutes.
The drain pump keeps run-
ning after the unit has
The drain pump is running
while the unit is stopped.
Outdoor unit, indoor unit, or
BC controller makes noise
when the operation mode is
switched between Cooling
and Heating.
Sound of the refrigerant flow is
heard from the indoor unit im-
mediately after starting opera-
Warm air sometimes comes
out of the indoor units that are
not in the heating mode.
Remote controller
"Cooling (heating)"
The unit cannot perform a heating (cooling) operation when other indoor
icon blinks on the
units on the same refrigerant system, are performing a cooling (heating)
After an hour of cooling operation with the auto vane in the vertical posi-
tion, the vane may automatically move into the horizontal position.
Normal display
Louver blades will automatically move into the horizontal position while
the unit is in the defrost mode, pre-heating stand-by mode, or when the
thermostat triggers unit off.
Very Low fan speed when "Thermo-OFF.' Changes from Very Low to pre-
Normal display
set fan speed when "Thermo-ON" depending on pipe temperature.
The fan remains stopped during defrost operation.
When the auxiliary heater is turned on, the fan operates for one minute
after stopping to dissipate heat.
The fan operates at extra low speed for 5 minutes after it is turned on or
until the pipe temperature reaches 35°C[95°F], then it operates at low
speed for 2 minutes, and finally it operates at the set speed.
(Pre-heating stand-by)
The system is starting up. Wait until the blinking display of "HO" or
"PLEASE WAIT" go off.
WAIT" icons blink
on the display.
The drain pump stays in operation for three minutes after the unit in the
cooling mode is stopped.
When drain water is detected, the drain pump goes into operation even
while the unit is stopped.
This noise is made when the refrigerant circuit is reversed and is normal.
Normal display
This is caused by the transient instability of the refrigerant flow and is nor-
Normal display
This is due to the fact that the LEVs on some of the indoor units are kept
slightly open to prevent the refrigerant in the indoor units that are not op-
Normal display
erating in the heating mode from liquefying and accumulating in the com-
pressor. It is part of a normal operation.
- 166 -

Hide quick links:


Table of Contents

Table of Contents