Mfz Microprocessor Control; Cool Operation; Dry Operation - Mitsubishi Electric MS-A WA Service Technical Manual

4

MFZ MICROPROCESSOR CONTROL

4-1. COOL ( ) OPERATION
1. Thermostat control
Refer to MXZ MICROPROCESSOR CONTROL, COOL OPERATION (3-8.1.).
2. Indoor fan speed control
Indoor fan operates continuously at the set speed by FAN SPEED CONTROL button regardless of the thermostat's OFF-
ON. In AUTO the fan speed is as follows.
Fan speed
High
Med.
Low
3. Coil frost prevention
Refer to MXZ MICROPROCESSOR CONTROL, COOL OPERATION (3-8.2.).
4-2. DRY ( ) OPERATION
The system for dry operation uses the same refrigerant circuit as the
cooling circuit.
The compressor and the indoor fan are controlled by the room tem-
perature.
By such controls, indoor flow amounts will be reduced in order to lower
humidity without much room temperature decrease.
1. Thermostat control
Refer to MXZ MICROPROCESSOR CONTROL, DRY OPERATION (3-9.1.).
2. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button. When thermostat OFF (compressor OFF) fan
speed becomes Very Low. In AUTO the fan speed is as follows.
Fan speed
High
Med.
Low
3. Coil frost prevention
Coil frost prevention is as same as COOL mode. (4-1.3.)
The indoor fan maintains the actual speed of the moment.
Room temperature minus
set temperature (Initial)
3.15°F(1.75°C) or more
between 1.8 and 3.15°F
less than 1.8°F(1°C)
Room temperature minus
set temperature (Initial)
3.15°F(1.75°C) or more
between 1.8 and 3.15°F
less than 1.8°F(1°C)
35
Room temperature minus
set temperature (During operation)
5.4°F
(3°C)
1.8°F 3.15°F
(1.75°C)
(1°C)
Set temperature and
°F
initial room temperature in dry mode
95
86
77
68
59
50
50 59 68 77
Initial room temperature
Room temperature minus
set temperature (During operation)
4.5°F
(2.5°C)
3.15°F
1.8°F
(1.75°C)
(1°C)
86 95 °F