Mitsubishi Electric MXZ-2D33VA, Service Manual

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The other cases
Indoor unit does not operate. (different operating models in multi system)
• When you try to run 2 indoor units simultaneously, one for cooling and the other for heating, the unit which transmits signal to
the outdoor unit first decides the operation mode.
• When the above situation occurs, set all the indoor units to the same mode, turn OFF the indoor units, then turn them back
ON.
• Though the top of the indoor unit sometimes gets warm, this does not mean malfunction.
The reason is that the refrigerant gas continuously flows into the indoor unit even while it is not operating.
Check of outdoor refrigerant circuit
Has the operation stopped
during pump down?
Was the operation started with
the stop valve closed, and was
it opened during operation?
No
Yes
The operation has stopped to pre-
vent the diesel explosion caused by
air trapped in the refrigerant circuit.
Close the stop valve, and disconnect
the power plug or turn the power sup-
ply OFF.
The unit occasionally stops when the
stop valve is opened or closed during
operation. Open the stop valve and
start the cooling operation again.
Yes
No
The refrigerant gas amount may be
60% or less than the normal amount.
Identify where the gas is leaking from,
and fi x the leak.
CAUTION : Do not start the opera-
tion again to prevent
hazards.
OBH626K