4-8 Automatic Restart after Power Interruption
This air conditionner has a power failure recovery function.
4-9 Electronic Expansion Control Valve
This valve allows very precise and smooth control of the amount of refrigerant flow in the system. Since the
valve is operated by a step motor, the control circuits can open or close it in very exact amounts, so the
degree of heating or cooling can be changed by just a little, or changed very quickly or slowly.
(Completely close …… 0 step)
(Full open................ 480 step)
Fuzzy Control
Fuzzy Control is a controlling system to control electronic refrigerant control valve using fuzzy logic. It
regulates the functions of heating and cooling, as well as some of the processes inside the unit, by taking
account of many different conditions of temperature, fan speed, etc. These control circuits work
automatically to send just the right amount of refrigerant through the Electronic Expansion Valve.
4-10 Dehumidifying Operation
Dehumidifying operation uses the cooling cycle to remove moisture from the air, but by running an indoor
fan at a low speed, to dehumidify without greatly lowering room temperature. In this mode, the
microprocessor automatically controls the ON-OFF operation b2 deg. and -2 deg. of the set
temperature.
A range:
When the room temperature is in this range, cooling operation starts. However, when the
temperature is below 18°C, the cooling operation does not start.
B range:
When the room temperature is in this range, the air conditioner automatically repeats the
dehumidifying cycle of 5 minutes ON, 3 minutes OFF – see Fig. 20 for details.
C range:
When the room temperature is in this range, the microprocessor shuts off the air conditioner.
100 - 200
Max. open
480 step
Standard condition
100 - 200
100 - 200
85 step
85 step
120 step
85 step
85 step
Min. open
HEAT
COOL
100 step
Model
25 type
36 type
48 type
Fig. 19
A
ROOM TEMP.
(DEG)
B
C
SET TEMP.
0448_M_S
+2deg
-2deg
23