Cooling Operation - Toshiba RAS-M10NKV-E Service Manual

6-2-2. Cooling Operation

(The Remote controller [MODE] Button
is Set to the COOL Position)
• Once the setting is made, the operation mode is
memorized in the microcomputer so that the same
operation can be effected thereafter simply by
pushing [ ] button.
• A cooling operation signal is transmitted to outdoor
unit.
• The indoor fan motor operates as shown in Fig.6-
2-2 when [FAN] button is set to AUTO.
• The motor operates with a constant air flow when
the [FAN] button is set to LOW, LOW + , MED, MED + ,
or HIGH.
• The outdoor unit controls the outdoor fan relay
R01, R02 and R03, and the compressor motor
speed according to the operation command signal
sent from the indoor unit.
˚C
+3
+2.5
+2
+1.5
+1
+0.5
Set
0
temp.
–0,5
NOTE :
1: Calculated from difference in motor speed of M+
*
and L–, and controlled.
Fig. 6-2-2 Setting of air flow [Air Flow AUTO]
(1) Cooling capacity control
• The cooling capacity and room temperature
are controlled by changing the compressor
motor speed according to both the difference
between the temperature detected by the room
temperature sensor and the temperature set by
[TEMP] button and also any change in room
temperature.
• When compressor has been activated or
reactivated, it operates with Max. 33 rps for 2
minutes and with Max. 57 rps from 2 to 4
minutes passed.
• When room temperature is lower than set
temperature and indoor fan motor is operated
at fan speed L– as shown in Fig. 6-2-2 while
the outdoor unit stops.
(2) Prevent-freezing control
If temperature of indoor heat exchanger detected
by the indoor heat exchanger sensor is 5°C or
lower, compressor motor speed is gradually
lowered to prevent freezing of the indoor heat
exchanger. If temperature is 7°C or higher, return
the operation to the above item (1).
(3) Current release control
The input current of compressor and outdoor fan
M+
motor (Precisely inverter main circuit control
section) which occupy most of air conditioner
*1
input is detected by the outdoor current sensor,
and compressor motor speed is gradually lowered
*1
so that current value does not exceed 11.5A if
*1
current value exceeds 11.5A. When the current
value lowers to 11.0A, return the operation to the
L–
above item (1).
In normal
operation
14.2
13.7
(4) Outdoor temperature release control
The outdoor temperature release is controlled by
changing the current release points 14.2 and 13.7
in the above item according to temperature
detected by the outdoor temperature sensor.
For example, if the outdoor temperature is 43°C,
the value of current release points becomes 9.6A.
− 12 −
FILE NO. SVM-05019
Comp. motor
speed down
Comp. motor
speed keep
Normal control
Fig. 6-2-3