Mitsubishi Electric MSZ-RW25VG Service Manual page 21

NOTE 1:
If 2 or more indoor units are operating in multi system, there might be a case that the indoor unit, which is operating in
(AUTO), cannot change over to the other operating mode (COOL ↔ HEAT) and becomes a state of standby.
Refer to NOTE 2 "FOR MULTI SYSTEM AIR CONDITIONER".
NOTE 2:
FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT: MXZ series
Multi system air conditioner can connect 2 or more indoor units with one outdoor unit.
• When you try to operate 2 or more indoor units with one outdoor unit simultaneously, one for the cooling and the
others for heating, the operation mode of the indoor unit that operates first is selected. Other indoor units cannot
operate, and operation indicator lamp blinks as shown in the figure below. In this case, please set all the indoor
units to the same operation mode.
• When indoor unit starts the operation while the defrosting of outdoor unit is being done, it takes a few minutes (max.
10 minutes) to blow out the warm air.
• In the heating operation, though indoor unit that does not operate may get warm or the sound of refrigerant flow-
ing may be heard, they are not malfunction. The reason is that the refrigerant continuously flows into it.
9-6. AUTO VANE OPERATION
1. Horizontal vane
(1) Vane motor drive
These models are equipped with stepping motors for the horizontal vanes. The rotating direction, speed, and angle of
the motor are controlled by pulse signals (approximately 12 V) transmitted from indoor microprocessor.
(2) The horizontal vane angle and mode change as follows by pressing VANE CONTROL (
AUTO
NOTE: The right and left horizontal vanes set to the same level may not align perfectly.
(3) Positioning
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane is set to the
selected angle.
Confirmation of standard position is performed in the following cases:
(a) When the operation starts or finishes (including timer operation).
(b) When the test run starts.
(c) When standby mode (only during multi system operation) starts or finishes.
(4) VANE AUTO ( ) mode
In VANE AUTO mode, the microprocessor automatically determines the vane angle to make the optimum room tem-
perature distribution.
In COOL and DRY operation
Vane angle is fixed to Horizontal position.
Horizontal
position
(5) STOP (operation OFF) and ON TIMER standby
In the following cases, the horizontal vane returns to the closed position.
(a) When OFF/ON (stop/operate) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When ON TIMER is ON standby.
(6) Dew prevention
During COOL or DRY operation with the lower position when the compressor cumulative operation time exceeds 1
hour, the vane angle automatically changes to Angle 1 for dew prevention.
OBH902A
OPERATION INDICATOR
1 2 3
21
Lit
Blinking
Not lit
4 5 SWING
In HEAT operation
Vane angle is fixed to Angle 4.
4
) button.