Summary of Contents for Mitsubishi Electric MSC-CA20VB
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Revision D: • MXZ-5A100VA - has been added. SPLIT-TYPE, AIR CONDITIONERS Please void OBT06 REVISED EDITION-C. SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS FLOOR AND CEILING TYPE AIR CONDITIONERS FLOOR TYPE, HEAT PUMP AIR CONDITIONERS No. OBT06 REVISED EDITION-D SERVICE TECHNICAL GUIDE Wireless type Models MSC-CA•VB - ·...
MSC MICROPROCESSOR CONTROL MSC-CA20VB MSC-CB20VB MSC-GA20VB MU-GA20VB MUH-GA20VB MUX-2A28VB MUX-3A63VB MSC-CA25VB MSC-CB25VB MSC-GA20VB MU-GA25VB MUH-GA25VB MUX-2A59VB MUX-2A70VB MSC-CA35VB MSC-CB35VB MSC-GA35VB MU-GA35VB MUH-GA35VB MUX-3A60VB MUX-4A73VB Once the operation mode is set, the same operation mode can be repeated by simply turning OPERATE/STOP (ON/OFF) but- ton ON.
3. Coil frost prevention Temperature control When the indoor coil thermistor RT12 reads 4°C or below(MSC-CA20/CA25/CB20/CB25/GA20/GA25VB) / 0°C or below(MSC-CA35/CB35/GA35VB) for 5 minutes, the coil frost prevention mode starts. The indoor fan operates at the set speed and the compressor stops for 5 minutes. After that, if RT12 still reads below 4°C (MSC-CA20/CA25/CB20/CB25/GA20/GA25VB) / 0°C (MSC-CA35/CB35/GA35VB), this mode is prolonged until RT12 reads over 4°C (MSC-CA20/CA25/CB20/CB25/GA20/GA25VB) / 0°C (MSC- CA35/CB35/GA35VB).
Operation time chart Example Thermostat Indoor fan Outdoor fan Compressor 8 minutes 3 minutes 4 minutes 1 minute 4. Coil frost prevention The operation is as same as coil frost prevention during COOL operation.(Refer to 1-1.3.) However when coil frost prevention works while the indoor fan is OFF, its speed becomes set speed. <...
(3) Warm air control When the following any conditions of 1 (a. ~ c.) and the condition of 2 are satisfied at the same time, warm air control works. 1 a.) When outdoor unit starts operating in HEAT mode. b.) When cold air prevention has been released. c.) When defrosting has been finished 2 When the temperature of indoor coil thermistor RT12 is less than 37°C.
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(4) The initial set temperature is decided by the initial room temperature. Initial room temperature Mode Initial set temperature MU & MUX type MUH type 26: or more 26: or more COOL mode of "I FEEL CONTROL" Initial room temperature 25: or more, 25: or more, less than 26:...
1-6. INDOOR FAN MOTOR CONTROL (1) Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (High,Med.,Low), the microprocessor controls SR141 and adjusts fan motor electric current to make the current rotational frequency close to the target rotational frequency.
< > (7) Cold air prevention in HEAT operation MUH-GA20/GA25/GA35VB When any of the following conditions occurs in HEAT operation, the horizontal vane angle changes to Angle 1 automat- ically to prevent cold air blowing on users. Compressor is not operating. Defrosting is performed.
(4) Press HR. and MIN. button to set the timer. Time setting is 10-minute units. HR. and MIN. button will work when “ ” or “ ” mark is flashing. These marks disappear in 1 minute. After setting ON timer, check that OPERATION INDICATOR lamp of the indoor unit lights. NOTE1 : Be sure to place the remote controller at the position where its signal can reach the air conditioner even during TIMER operation, or the set time may deviate within the range of about 10 minutes.
1-10. OUTDOOR UNIT ACTUATOR CONTROL MUX-2A28VB MUX-2A59VB MUX-2A70VB INDOOR UNIT INDOOR UNIT ACTUATOR ACTUATOR – COMPRE- COMPRE- – SSOR SSOR – – ANY UNIT ON ANY UNIT ON OUTDOOR OUTDOOR MF61 FAN MOTOR FAN MOTOR ON (CLOSE) MUX-4A73VB (BALANCE) INDOOR UNIT SOLENOID ACTUATOR OFF (OPEN)
MS MICROPROCESSOR CONTROL MS-GA50VB MU-GA50VB MS-GA60VB MU-GA60VB MS-GA80VB MU-GA80VB WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE/ STOP (ON/ OFF) button ON/OFF WARM COOL TEMPERATURE buttons CLOCK ON/OFF WARM COOL VANE button FAN SPEED CONTROL button (Horizontal vane button) STOP I FEEL COOL OFF-TIMER button...
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• Once the mode is fixed, the mode does not change by room temperature afterwards. • Under the ON-TIMER ( ) operation, mode is determined as follows. When the system is stopped on the remote controller, and restarted within 2 hours in “I FEEL CONTROL” ( ) mode, the system operates in previous mode automatically regardless of the room temperature.
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2-1-1. COOL mode of “I FEEL CONTROL” 1. Indoor fan speed control Indoor fan operates at the set speed by FAN SPEED CONTROL button. Difference between room In AUTO the fan speed is as follows. temperature and set temperature during operation Initial temperature difference Fan Speed Room temperature minus set temperature : 1.7 °C or more···································High...
2-1-2. DRY mode of “I FEEL CONTROL” 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 temperature. By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature decrease. 1.
2-3. DRY ( ) OPERATION (1) Press OPERATE/STOP (ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room tempera- ture and determines the set temperature. Set temperature is as shown on the right chart.
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(3) Positioning The vane presses the vane stopper once to confirm the standard position and then moves to the set angle. Confirming of standard position is performed in case of follows. (a) When the power supply turns ON. (b) When the operation starts or finishes (including timer operation). (c) When the test run starts.
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(8) ECONO COOL ( ) operation (ECONOmical operation) When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2°C higher. Also the horizontal vane swings in various cycle according to the temperature of indoor heat exchanger(Tp (w 1) SWING operation makes you feel cooler than set temperature.
2. Vertical vane (1) Vane motor drive These models are equipped with a stepping motor for the vertical vane. The rotating direction, speed, and angle of the motor are controlled by pulse signals (approx. 12V) transmitted from microprocessor. (2) The vertical vane angle and mode change as follows by pressing WIDE VANE button. SWING (3) Positioning The vane is once pressed to the vane stopper to confirm the standard position and then set to the desired angle.
PROGRAM TIMER • OFF timer and ON timer can be used in combination. • “ ” and “ ” display shows the order of OFF timer and ON timer operation. (Example 1) The current time is 8:00 PM. (Example 2) The current time is 11:00 AM. The unit turns off at 11:00 PM, and on at 6:00 AM.
2-9. EXPANSION VALVE CONTROL (LEV CONTROL) <MU-GA80VB> LEV (Expansion valve) is controlled by “Thermostat ON” commands given from the unit. Controlled range Minimum : 54 pulse, Maximum : 500 pulse 30 ~ 90 pulse / second Drive speed Opening set The setting is always in opening direction.
2 When the temperature difference RT between indoor coil thermistor (main) RT12 and indoor coil thermistor (sub) RT13 in the indoor unit is 2: or more for a fixed time at cool or dry operation, the target discharge temperature is changed.
MSH MICROPROCESSOR CONTROL MSH-CA50VB MSH-GA50VB MUH-GA50VB MSH-CB50VB MSH-GA60VB MUH-GA60VB MSH-GA80VB MUH-GA80VB WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE /STOP (ON /OFF) button ON/OFF WARM COOL TEMPERATURE buttons CLOCK ON/OFF WARM COOL VANE button FAN SPEED CONTROL button STOP (Horizontal vane button) I FEEL COOL...
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• Once the mode is fixed, the mode does not change by room temperature afterwards. • Under ON-TIMER ( ) operation, mode is determined as follows. When the system is stopped on the remote controller, and restarted within 2 hours in “I FEEL CONTROL” ( ) mode, the system operates in previous mode automatically regardless of the room temperature.
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3-1-1. COOL mode of “I FEEL CONTROL” 1. Indoor fan speed control Indoor fan operates at the set speed by FAN SPEED CONTROL button. Difference between room In AUTO the fan speed is as follows. temperature and set temperature Initial temperature difference Fan Speed during operation Room temperature minus set temperature : 1.7 : or more····································High...
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3-1-2. DRY mode of “I FEEL CONTROL” 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 temperature. By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature decrease. 1.
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(2) Cold air prevention control The fan runs at set speed when the indoor coil thermistor RT12 temperature exceeds 22°C. The fan operates Low when the temperature of indoor coil thermistor RT12 is below 18°C. But the fan stops when the indoor fan operates at Very Low and the room temperature is 15°C or less.
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<MUH-GA80VB> During heating operation, the outdoor fan and the compressor are controlled by the temperature of indoor coil thermistor RT12 for excess rise protection of compressor discharge pressure. • Outdoor fan When the temperature of indoor coil thermistor RT12 goes to 55: or more, the outdoor fan is turned OFF. When the temperature of indoor coil thermistor RT12 becomes to 52: or less, the outdoor fan is turned ON.
3-2. COOL ( ) OPERATION (1) Press OPERATE/STOP (ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons. (TOO WARM or TOO COOL button) to select the desired temperature.
3-6. AUTO VANE OPERATION 1. Horizontal vane (1) Vane motor drive These models are equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of the motor are controlled by pulse signals (approx. 12V) transmitted from indoor microprocessor. (2) The horizontal vane angle and mode change as follows by pressing the VANE button.
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(9) ECONO COOL ( ) operation (ECONOmical operation) When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2°C higher. Also the horizontal vane swings in various cycle according to the temperature of indoor heat exchanger(Tp (w 1) SWING operation makes you feel cooler than set temperature.
2. Vertical vane (1) Vane motor drive These models are equipped with a stepping motor for the vertical vane. The rotating direction, speed, and angle of the motor are controlled by pulse signals (approx. 12V) transmitted from microprocessor. (2) The vertical vane angle and mode change as follows by pressing the WIDE VANE button. SWING (3) Positioning The vane is once pressed to the vane stopper to confirm the standard position and then set to the desired angle.
2. Cancel TIMER setting can be cancelled with the ON/OFF TIMER buttons. To cancel ON timer, press “ON-TIMER” button. To cancel OFF timer, press “OFF-TIMER” button. TIMER is cancelled and the display of set time disappears. PROGRAM TIMER • OFF timer and ON timer can be used in combination. •...
3-9. EXPANSION VALVE CONTROL (LEV CONTROL) <MUH-GA80VB> LEV (Expansion valve) is controlled by “Thermostat ON” commands given from the unit. Controlled range Minimum : 54 pulse, Maximum : 500 pulse 30 ~ 90 pulse / second Drive speed Opening set The setting is always in opening direction.
2 When the temperature difference RT between indoor coil thermistor (main) RT12 and indoor coil thermistor (sub) RT13 in the indoor unit is 2: or more for a fixed time at cool or dry operation, the target discharge temperature is changed.
MSZ-CA MICROPROCESSOR CONTROL MSZ-CA25VB MUZ-CA25VB MSZ-CA35VB MUZ-CA35VB WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE /STOP (ON /OFF) button ON/OFF WARM COOL TEMPERATURE buttons Indication of remote controller model is on back ˚C CLOCK AM PM ON/OFF WARM COOL FAN SPEED CONTROL button VANE CONTROL button...
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• Once the mode is fixed, the mode does not change by room temperature afterwards. • Under ON-TIMER ( ) operation, mode is determined as follows. When the system is stopped on the remote controller, and restarted within 2 hours in “I FEEL CONTROL” ( ) mode, the system operates in previous mode automatically regardless of the room temperature.
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4-1-1. COOL mode of “I FEEL CONTROL” Difference between room temperature and set temper- 1. Thermostat control ature during operation. Thermostat is ON or OFF by difference between room temperature and set temperature Initial temperature difference Thermostat Set temperature Room temperature minus set temperature : 0.3 : or more················································ON Room temperature minus set temperature : less than -0.3 :············································OFF -0.3 2.
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4-1-2. DRY mode of “I FEEL CONTROL” 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 temperature. By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature decrease. Difference between room temperature and set tem- 1.
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(3) Warm air control When the following conditions of a) ~ b) are satisfied, warm air control works. a) when cold air prevention has been released after the compressor started operation b) when defrosting has been finished When warm air control works, the fan speed changes from Low as follows to blow out warm air gradually. When every 2 minutes have passed (1) if the temperature of RT12 is 22°C or more, the indoor fan speed is up by 1 step.
Time chart of defrosting in HEAT mode (reverse type) <indoor unit> horizontal set position set position Horizontal vane Indoor fan Very Low (temperature of indoor coil thermistor > 18:) set speed set speed seconds <outdoor unit> Maximum frequency Compressor normal seconds seconds seconds...
4-3. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C 1.
4-6. INDOOR FAN MOTOR CONTROL 1. Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feed- back the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (High, Med.,Low) the microprocessor controls SR141 and adjusts fan motor electric current to make the current rotational fre- quency close to the target rotational frequency.
(7) SWING MODE ( By selecting SWING mode with VANE CONTROL button, the horizontal vane swings vertically. The remote controller displays “ ” . SWING mode is cancelled when VANE CONTROL button is pressed once again. (8) Cold air prevention in HEAT operation. When any of the following conditions occurs in HEAT operation, the vane angle changes to Angle 1 automatically to pre- vent cold air blowing on users.
NOTE1 : Be sure to place the remote controller at the position where its signal can reach the air conditioner even during TIMER operation, or the set time may deviate within the range of about 10 minutes. NOTE2 : Reset the timer in the following cases, or the set time may deviate and other malfunctions may occur. A power failure occurs.
4-10. INVERTER SYSTEM CONTROL 4-10-1. Inverter main power supply circuit POWER P.C. BOARD INVERTER P.C. BOARD DB61 Power R64A R64B C62A supply CT761 C62B C61B CT781 TR821 DB65 Booster chopper circucuit Function of main parts SYMBOL NAME FUNCTION It supplies three-phase AC power to compressor. INTELLIGENT POWER MODULE It stabilizes the DC voltage.
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3. Purpose of PAM adoption PAM : Pulse Amplitude Modulation PAM has been adopted for the efficiency improvement and the adaptation to IEC harmonic current emission standard. Outline of simple partial switching method In conventional inverter models, diode module rectifies AC voltage to DC voltage, smoothing capacitor makes its DC waveform smooth, and IPM converts its DC voltage to imitated AC voltage again in order to drive the compressor motor.
4-10-4. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
4-12. EXPANSION VALVE CONTROL (LEV CONTROL) (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each opera- tional frequency of the compressor. However, when any change in indoor/outdoor temperatures or other factors cause air conditioning load fluctuation, the LEV control also works to correct LEV opening degree based on discharge temper- ature (Shell temperature) of the compressor, developing the unit’s performance.
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(2) Time chart Air conditioner OFF (thermostat off) Air conditioner ON Positioning Opening degree is corrected according to discharge Standard Commanded temperature. opening to open degree about 15 minutes Time OFF Time (3) Control data (a) Reference value of target discharge temperature (COOL/HEAT :) Applied model MUZ-CA25VB...
5-1. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. POWER lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C Difference between room temperature and set temper-...
5-2. DRY ( ) OPERATION Set temperature and initial room temperature in dry mode (1) Press OPERATE/STOP(ON/OFF) button. POWER lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room temperature and determines the set temperature.
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3. High pressure protection In HEAT operation the indoor coil thermistor detects the temperature of the indoor heat exchanger. The compressor opera- tional frequency is controlled to prevent the condensing pressure from increasing excessively. 4. Overload starting When the room temperature thermistor RT11 reads 18°C or more, the compressor runs with its maximum frequency regulat- ed for 10 minutes after the start-up.
Time chart of defrosting in HEAT mode (reverse type) <indoor unit> horizontal set position set position Horizontal vane Indoor fan Very Low (temperature of indoor coil thermistor > 18:) set speed set speed seconds <outdoor unit> Maximum frequency Compressor normal seconds seconds seconds...
5-5. INDOOR FAN MOTOR CONTROL (1) Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (Super High, High, Med., Low), the microprocessor adjusts fan motor electric current to make the current rotational frequency close to the target rotational frequency.
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(4) VANE AUTO ( ) mode The microprocessor automatically determines the vane angle and operation to make the optimum room temperature dis- tribution. COOL and DRY operation HEAT operation Vane angle is fixed to Horizontal position. Vane angle is fixed to Angle 4. Horizontal position (5) STOP (operation OFF) and ON-TIMER standby...
(10) ECONO COOL ( ) operation (ECONOmical operation) When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2°C higher. Also the horizontal vane swings in various cycle according to the temperature of indoor heat exchanger(RT12). SWING operation makes you feel cooler than set temperature.
i-see Sensor i-see Sensor, which is installed on the right side of the air outlet of the indoor unit, is moved with the stepping motor and it detects the floor/ wall temperature. Enlarged view of i-see Sensor i-see Sensor is installed here. i-see Sensor ·...
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(4) AREA setting is cancelled when the "cancel" is sellected by pressing AREA button, or when WIDE VANE button is pressed. Indoor unit installation location and air-conditioning area Installed at left Installed at center Installed at right LEFT RIGHT LEFT RIGHT LEFT RIGHT...
5-10. PLASMA DUO ( ) OPERATION (1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner. PLASMA/WASH lamp (2) Press PLASMA button to set PLASMA DUO operation. Each time this b utton is pressed, the oper ation mode of PLASMA is changed in sequence: Lighted Cancel (The sign of PLASMA oper ation disappears .)
5-11. AUTO FRONT PANEL When the unit starts operating, the front panel opens automatically to draw in air. When the unit stops operating, the front panel closes automatically. Open Closed Operation and operating range of the auto front panel The front panel fully opens 10 mm or more upper than the level line of the top end of the nozzle assembly. It takes about 13 seconds to open the front panel completely.
PROGRAM TIMER • The OFF timer and ON timer can be used in combination. The timer of the set time that is reached first will operate first. • “ ” and “ ” display shows the order of the OFF timer and the ON timer operation. (Example 1) The current time is 8:00 PM.
5-14. INVERTER SYSTEM CONTROL 5-14-1. Inverter main power supply circuit POWER P.C. BOARD INVERTER P.C. BOARD DB61 Power R64A R64B C63A CT761 supply C63B C63C CT781 TR821 DB65 Booster chopper circucuit Function of main parts SYMBOL NAME FUNCTION It supplies three-phase AC power to compressor. INTELLIGENT POWER MODULE It stabilizes the DC voltage.
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3. Purpose of PAM adoption PAM : Pulse Amplitude Modulation PAM has been adopted for the efficiency improvement and the adaptation to IEC harmonic current emission standard. Outline of simple partial switching method In conventional inverter models, diode module rectifies AC voltage to DC voltage, smoothing capacitor makes its DC waveform smooth, and IPM converts its DC voltage to imitated AC voltage again in order to drive the compressor motor.
5-14-3. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
5-16. EXPANSION VALVE CONTROL (LEV CONTROL) (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each opera- tional frequency of the compressor. However, when any change in indoor/outdoor temperatures or other factors cause air conditioning load fluctuation, the LEV control also works to correct LEV opening degree based on discharge temper- ature (Shell temperature) of the compressor, developing the unit’s performance.
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(2) Time chart Air conditioner OFF (thermostat off) Air conditioner ON Positioning Opening degree is corrected according to discharge Standard Commanded temperature. opening to open degree about 5 minutes <COOL, DRY> Time about 15 minutes <HEAT> OFF Time (3) Control data (a) Reference value of target discharge temperature (COOL/HEAT :) MUZ-FA25VA...
MSZ-GA • MSZ-CB MICROPROCESSOR CONTROL MSZ-GA22VA MSZ-CB22VA MSZ-GA25VA MSZ-CB25VA MUZ-GA25VA MUZ-GA25VAH MSZ-GA35VA MSZ-CB35VA MUZ-GA35VA MUZ-GA35VAH WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE/STOP (ON/OFF) button Temperature buttons Indication of remote controller model is on back (This diagram shows an overall view.) FAN SPEED CONTROL button OFF-TIMER button OPERATION SELECT button...
6-1. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C Difference between room temperature and set temper-...
Set temperature and 6-2. DRY ( ) OPERATION initial room temperature in dry mode (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room temperature and determines the set temperature.
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3. High pressure protection In HEAT operation the indoor coil thermistor detects the temperature of the indoor heat exchanger. The compressor opera- tional frequency is controlled to prevent the condensing pressure from increasing excessively. 4. Overload starting When the room temperature thermistor RT11 reads 18°C or more, the compressor runs with its maximum frequency regulat- ed for 10 minutes after the start-up.
Time chart of defrosting in HEAT mode (reverse type) <indoor unit> horizontal set position set position Horizontal vane Indoor fan Very Low (temperature of indoor coil thermistor > 18:) set speed set speed seconds <outdoor unit> Maximum frequency Compressor normal seconds seconds seconds...
6-5. INDOOR FAN MOTOR CONTROL (1) Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (Super High, High, Med., Low), the microprocessor adjusts fan motor electric current to make the current rotational frequency close to the target rotational frequency.
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(4) VANE AUTO ( ) mode The microprocessor automatically determines the vane angle and operation to make the optimum room temperature dis- tribution. HEAT operation COOL and DRY operation Vane angle is fixed to Horizontal position. Vane angle is fixed to Angle 4. Horizontal position (5) STOP (operation OFF) and ON-TIMER standby...
(10) ECONO COOL ( ) operation (ECONOmical operation) When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2°C higher. Also the horizontal vane swings in various cycle according to the temperature of indoor heat exchanger(RT12). SWING operation makes you feel cooler than set temperature.
PROGRAM TIMER • OFF timer and ON timer can be used in combination. The timer of the set time that is reached first will operate first. • “ ” and “ ” display shows the order of OFF timer and ON timer operation. (Example 1) The current time is 8:00 PM.
6-10. INVERTER SYSTEM CONTROL 6-10-1. Inverter main power supply circuit POWER P.C. BOARD INVERTER P.C. BOARD DB61 Power R64A R64B C63A CT761 supply C63B C63C CT781 TR821 DB65 Booster chopper circucuit Function of main parts SYMBOL NAME FUNCTION It supplies three-phase AC power to compressor. INTELLIGENT POWER MODULE It stabilizes the DC voltage.
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3. Purpose of PAM adoption PAM : Pulse Amplitude Modulation PAM has been adopted for the efficiency improvement and the adaptation to IEC harmonic current emission standard. Outline of simple partial switching method In conventional inverter models, diode module rectifies AC voltage to DC voltage, smoothing capacitor makes its DC waveform smooth, and IPM converts its DC voltage to imitated AC voltage again in order to drive the compressor motor.
6-10-3. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
6-12. EXPANSION VALVE CONTROL (LEV CONTROL) MUZ-GA35 (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each opera- tional frequency of the compressor. However, when any change in indoor/outdoor temperatures or other factors cause air conditioning load fluctuation, the LEV control also works to correct LEV opening degree based on discharge temper- ature (Shell temperature) of the compressor, developing the unit’s performance.
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(2) Time chart Air conditioner OFF (thermostat off) Air conditioner ON Positioning Opening degree is corrected according to discharge Standard Commanded temperature. opening to open degree about 5 minutes <COOL, DRY> Time about 15 minutes <HEAT> OFF Time (3) Control data (a) Reference value of target discharge temperature (COOL/HEAT :) Applied model...
2. Indoor fan speed control Indoor fan operates continuously at the set speed by FAN SPEED CONTROL button Difference between room regardless of the thermostat’s OFF-ON. temperature and set tempera- In AUTO the fan speed is as follows. ture during operation Initial temperature difference Fan speed Room temperature minus set temperature : 1.7 : or more ········································High...
Difference between room temperature and set tem- 1. Thermostat control perature during operation Thermostat is ON or OFF by difference between room temperature and set temperature. Initial temperature difference Thermostat Set temperature Room temperature minus set temperature : -1.0 : or more··············································ON Room temperature minus set temperature : less than -1.0 :············································OFF -1.0 -0.7...
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3. High pressure protection In HEAT operation the indoor coil thermistor detects the temperature of the indoor heat exchanger. The compressor opera- tional frequency is controlled to prevent the condensing pressure from increasing excessively. 4. Overload starting When the room temperature thermistor RT11 reads 18°C or more, the compressor runs with its maximum frequency regulat- ed for 10 minutes after the start-up.
6-16. AUTO CHANGE OVER ··· AUTO MODE OPERATION Once desired temperature is set, unit operation is switched automatically between COOL and HEAT operation. 1. Mode selection (1) Initial mode At first indoor unit operates only indoor fan with outdoor unit OFF for 3 minutes to detect present room temperature. Following the conditions below, operation mode is selected.
6-18. OUTDOOR FAN MOTOR CONTROL Fan speed is switched according to the compressor frequency. Fan speed Down High Min. Compressor frequency Max. <Relation between compressor frequency and fan speed> Compressor frequency Mode Fan speed MUZ-GA50/GA60 MUZ-GA71 44Hz 54Hz COOL Down 33Hz 39Hz 44Hz...
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(7) SWING MODE ( By selecting SWING mode with VANE CONTROL button, the horizontal vane swings vertically. The remote controller displays “ ” . SWING mode is cancelled when VANE CONTROL button is pressed once again. (8) Cold air prevention in HEAT operation When any of the following conditions occurs in HEAT operation, the vane angle changes to Horizontal position automati- cally to prevent cold air blowing on users.
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(10) LONG MODE ( By pressing LONG button indoor fan speed becomes faster than setting fan speed on the remote controller, and the hor- izontal vane moves to the position for LONG mode. The remote controller displays “ ”. LONG mode is cancelled when LONG button is pressed once again or VANE button is pressed or ECONO COOL button is pressed in COOL mode.
6-20. TIMER OPERATION 1. How to set the timer (1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of TIME MONITOR, so set the current time correctly with CLOCK SET button.
6-21. EMERGENCY / TEST OPERATION In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of remote con- troller run down.
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6-22-2. Outline of main power supply circuit 1. At the start of operation Main power supply circuit is formed when X64 (Relay) is turned ON at compressor startup. To prevent rush current from running into the circuit when power supply is turned ON, R64A and R64B (Current-limiting resistor) are placed in sub circuit.
6-22-4. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
6-24. EXPANSION VALVE CONTROL (LEV CONTROL) (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each opera- tional frequency of the compressor. However, when any change in indoor/outdoor temperatures or other factors cause air conditioning load fluctuation, the LEV control also works to correct LEV opening degree based on discharge temper- ature (Shell temperature) of the compressor, developing the unit’s performance.
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(2) Time chart Air conditioner OFF (thermostat off) Air conditioner ON Positioning Opening degree is corrected according to discharge Standard Commanded temperature. opening to open degree about 5 minutes <COOL, DRY> Time about 15 minutes <HEAT> OFF Time (3) Control data (a) Reference value of target discharge temperature (COOL/HEAT :) Applied model...
MCF MICROPROCESSOR CONTROL MCF-GA35VB MUCF-GA35VB MCF-GA50VB MUCF-GA50VB MCF-GA60VB MUCF-GA60VB Once the operation mode is set, the same operation mode WIRELESS REMOTE CONTROLLER can be repeated by simply turning OPERATE/STOP (ON/OFF) Signal transmitting section button ON. Indoor unit receives the signal with a beep tone. When the system turns off, 3-minute time delay will operate to protect system from overload and compressor will not restart Operation display section...
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(4) The initial set temperature is decided by the initial room temperature. Model Initial room temperature Initial set temperature 26°C or more 24°C COOL mode of “I FEEL CONTROL” Initial room temperature 25°C to 26°C minus 2°C Initial room temperature DRY mode of 13°C to 25°C minus 2°C...
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Time control When the three conditions as follows have been satisfied for 1 hour and 45 minutes, compressor stops for 3 minutes. The indoor fan operates at set speed. a. Compressor has been continuously operating. b. Indoor fan speed is Low or Med. c.
7-2. COOL ( ) OPERATION (1) Press OPERATE/STOP (ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons. (TOO WARM or TOO COOL button) The setting range is 16 ~ 31°C.
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(4) VANE AUTO ( ) mode The microprocessor automatically determines the vane angle and operation to make the optimum room temperature distri- bution. COOL and DRY operation FAN operation Vane angle is fixed to Angle 1. Vane angle is fixed to Angle 4. (5) STOP and ON-TIMER standby When the following cases occur, the vane returns to the closed position.
7-6. TIMER OPERATION 1. How to set the timer (1) Press OPERATE/STOP(ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of TIME MONITOR, so set the current time correctly with CLOCK SET button.
MCFH MICROPROCESSOR CONTROL MCFH-GA35VB MUCFH-GA35VB MCFH-GA50VB MUCFH-GA50VB MCFH-GA60VB MUCFH-GA60VB Once the operation mode is set, the same operation mode can be repeated by simply turning OPERATE/STOP WIRELESS REMOTE CONTROLLER (ON/OFF) button ON. Indoor unit receives the signal with a beep tone. Signal transmitting section When the system turns off, 3-minute time delay will operate to protect system from overload and compressor will not...
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(4) The initial set temperature is decided by the initial room temperature. Initial room temperature Initial set temperature Model 26: or more COOL mode of "I FEEL CONTROL" Initial room temperature 25: to 26: minus 2: Initial room temperature DRY mode of 23: to 25: "I FEEL CONTROL"...
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When compressor stops, the accumulated time is cancelled and when compressor restarts, time counting starts from the beginning. Time counting also stops temporarily when the indoor fan speed becomes High or the room temperature exceeds 26°C. However, when two of the above conditions (b. and c.) are satisfied again, time accumulation is resumed. Operation chart Example Compressor...
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2. Indoor fan speed control Difference between room (1) In AUTO the fan speed is as follows. temperature and set temperature Initial temperature difference Fan speed during operation Set temperature minus room temperature: 2 °C or more ····································High Set temperature minus room temperature: Between 1 and 2 °C ························Med. Set temperature minus room temperature: less than 1 °C ··································Low 1.7: (2) Cold air prevention control...
4. Defrosting Defrosting of outdoor heat exchanger is controlled by DEICER P.C. board, with detection by the defrost thermistor RT61. (1) Starting conditions of defrost When all conditions of a) ~ c) are satisfied, the defrosting operation starts. a) The compressor cumulative operation time exceeds 40 minutes without the defrosting operation working. b) The defrost thermistor RT61 reads - 3°C or less.
Set temperature and initial room temperature in DRY mode 8-3. DRY ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room temperature and determines the set temperature.
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(5) STOP (operation OFF) and ON-TIMER standby When the following cases occur, the vane returns to the closed position. (a) When OPERATE/STOP (ON/OFF) 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 at Angle 4 or 5 when the compressor cumulative operation time exceeds 1 hour, the angle of horizontal vane automatically changes to Angle 1 for dew prevention.
8-6. TIMER OPERATION 1. How to set the timer (1) Press OPERATE/STOP(ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of TIME MONITOR, so set the current time correctly with CLOCK SET button.
8-7. EMERGENCY / TEST OPERATION In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of remote con- troller run down.
MFZ MICROPROCESSOR CONTROL MFZ-KA25VA MFZ-KA35VA MFZ-KA50VA WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE/STOP (ON/OFF) button Temperature buttons Indication of Open the front lid. remote controller model is on back verall view.) (This diagram shows an overall view.) .) i save button FAN SPEED CONTROL button OFF-TIMER button...
9-1. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. POWER lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C Difference between room temperature and set temper-...
9-2. DRY ( ) OPERATION Set temperature and initial room temperature in dry mode (1) Press OPERATE/STOP(ON/OFF) button. POWER lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room temperature and determines the set temperature.
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(2) Cold air prevention control 1 When the compressor is not operating, (1) if the temperature of room temperature thermistor RT11 is less than 19°C, the fan stops. (2) if the temperature of room temperature thermistor RT11 is 19°C or more and (1) if the temperature of indoor coil thermistor is less than 0°C, the fan stops.
Time chart of defrosting in HEAT mode (reverse type) <indoor unit> vertical set position set position Horizontal vane Indoor fan (upper) Very Low (temperature of indoor coil thermistor > 18:) set speed set speed seconds Indoor fan (lower) Damper OPEN or CLOSE OPEN or CLOSE CLOSE Maximum frequency...
9-5. INDOOR FAN MOTOR CONTROL (1) Rotational frequency feedback control The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (Super High, High, Med., Low), the microprocessor adjusts fan motor electric current to make the current rotational frequency close to the target rotational frequency.
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(4) VANE AUTO ( ) mode The microprocessor automatically determines the vane angle and operation to make the optimum room temperature dis- tribution. COOL and DRY operation HEAT operation Vane angle is fixed to Angle 1. When air comes out from upper air outlet, vane angle is fixed to Angle 5.
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(9) Damper operation NOTE 1 : Be sure to turn off the air conditioner before changing the switch setting. With this function, air comes out simultaneously from the upper and lower air outlets so that the room can be cooled or heated effectively. This function is set using the switch behind the front grille of the indoor unit.
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(10) EMBEDDING THE INDOOR UNIT IN A WALL • When installing a grating, use a grating with narrow upper and lower horizontal bars so that the airflow from the upper and lower air outlets does not contact the bars. If the horizontal bars will block the lower air outlet, use a stand, etc., to adjust the height of the indoor unit.
<SWING operation> In swing operation of ECONO COOL operation mode, the initial air flow direction is adjusted to “Horizontal”. According to the temperature of indoor coil thermistor RT12 at starting of this operation, next downward blow time is decided. Then when the downward blow has been finished, next horizontal blow time is decided. For initial 10 minutes the swing operation is performed in table G~H for quick cooling.
9-9. TIMER OPERATION 1. How to set the timer (1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of TIME MONITOR, so set the current time correctly with CLOCK SET button.
9-10. EMERGENCY / TEST OPERATION In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of the remote controller run down.
MSZ-HA MICROPROCESSOR CONTROL MSZ-HA25VA MUZ-HA25VA MSZ-HA35VA MUZ-HA35VA WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section ON/OFF (operate/stop) button Temperature buttons Fan speed control button ECONO COOL button Vane control button Operation select button Timer mode select button Time set buttons RESET button Once the operation mode is set, the same operation mode can be repeated by simply turning OPERATE/STOP (ON/OFF) button ON.
10-1. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C Difference between room temperature and set temper-...
10-3. HEAT ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select HEAT mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button) to select the desired temperature. The setting range is 16 ~ 31°C.
Time chart of defrosting in HEAT mode (reverse type) <indoor unit> horizontal set position set position Horizontal vane Indoor fan Very Low (temperature of indoor coil thermistor > 18:) set speed set speed seconds <outdoor unit> Maximum frequency Compressor normal seconds seconds seconds...
10-5. AUTO VANE OPERATION 1. Horizontal vane (1) Vane motor drive These models are equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of the motor are controlled by pulse signals (approx. 12V) transmitted from indoor microprocessor. (2) The horizontal vane angle and mode change as follows by pressing VANE CONTROL button.
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(9) To change the air flow direction not to blow directly onto your body. To change the air HEAT When to use this function? COOL/DRY flow direction Pressing and holding Use this function if you don’t The air conditioner starts the The air conditioner starts heat- want the air from the indoor cooling or drying operation...
10-6. TIMER OPERATION (ON/OFF TIMER) 1. How to set the timer (1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner. SELECT (2) Select the timer mode by pressing the button during operation. Each time this button is pressed, the timer mode is changed in sequence: (OFF TIMER) (ON TIMER) TIMER RELEASE...
10-8. INVERTER SYSTEM CONTROL 10-8-1. Inverter main power supply circuit POWER P.C. BOARD INVERTER P.C. BOARD DB61 Power R64A R64B C63B CT761 supply C63C CT781 TR821 DB65 Booster chopper circucuit Function of main parts SYMBOL NAME FUNCTION It supplies three-phase AC power to compressor. INTELLIGENT POWER MODULE It stabilizes the DC voltage.
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3. Purpose of PAM adoption PAM : Pulse Amplitude Modulation PAM has been adopted for the efficiency improvement and the adaptation to IEC harmonic current emission standard. Outline of simple partial switching method In conventional inverter models, diode module rectifies AC voltage to DC voltage, smoothing capacitor makes its DC waveform smooth, and IPM converts its DC voltage to imitated AC voltage again in order to drive the compressor motor.
10-8-3. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
MSZ-GB MICROPROCESSOR CONTROL MSZ-GB50VA MUZ-GB50VA WIRELESS REMOTE CONTROLLER Signal transmitting section Operation display section OPERATE/STOP (ON/OFF) button Temperature buttons Indication of remote controller model is on back (This diagram shows an overall view.) FAN SPEED CONTROL button OFF-TIMER button OPERATION SELECT button ON-TIMER button ECONO COOL button TIME SET buttons...
11-1. COOL ( ) OPERATION (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select COOL mode with OPERATION SELECT button. (3) Press TEMPERATURE buttons (TOO WARM or TOO COOL button)to select the desired temperature. The setting range is 16 ~ 31°C Difference between room temperature and set temper-...
Set temperature and 11-2. DRY ( ) OPERATION initial room temperature in dry mode (1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone. (2) Select DRY mode with OPERATION SELECT button. (3) The microprocessor reads the room temperature and determines the set temperature.
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3. High pressure protection In HEAT operation the indoor coil thermistor detects the temperature of the indoor heat exchanger. The compressor opera- tional frequency is controlled to prevent the condensing pressure from increasing excessively. 4. Overload starting When the room temperature thermistor RT11 reads 18°C or more, the compressor runs with its maximum frequency regulat- ed for 10 minutes after the start-up.
11-4. AUTO CHANGE OVER ··· AUTO MODE OPERATION Once desired temperature is set, unit operation is switched automatically between COOL and HEAT operation. 1. Mode selection (1) Initial mode At first indoor unit operates only indoor fan with outdoor unit OFF for 3 minutes to detect present room temperature. Following the conditions below, operation mode is selected.
11-6. OUTDOOR FAN MOTOR CONTROL Fan speed is switched according to the compressor frequency. Fan speed Down High Min. Compressor frequency Max. <Relation between compressor frequency and fan speed> Mode Fan speed Compressor frequency(Hz) COOL Down HEAT Down 11-7. AUTO VANE OPERATION 1.
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(8) Cold air prevention in HEAT operation. When any of the following conditions occurs in HEAT operation, the vane angle changes to Horizontal position automati- cally to prevent cold air blowing on users. Compressor is not operating. Defrosting is performed. Indoor coil thermistor RT12 reads 24: or below.
11-8. TIMER OPERATION 1. How to set the timer (1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of TIME MONITOR, so set the current time correctly with CLOCK SET button.
11-9. EMERGENCY/TEST OPERATION In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of the remote controller run down.
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11-10-2. Outline of main power supply circuit 1. At the start of operation Main power supply circuit is formed when X64 (Relay) is turned ON at compressor startup. To prevent rush current from running into the circuit when power supply is turned ON, R64A and R64B (Current-limiting resistor) are placed in sub circuit.
11-10-4. Characteristics of sine wave control in case of brushless DC motor Although ordinary three-phase induction motor requires energy to excite the magnetic field of rotor, brushless DC motor doesn't need it. So, higher efficiency and torque are provided. This control provides the most efficient waveform corresponding to the rotation times of compressor motor. The rotation can be set to higher compared to the conventional motor drive system.
11-12. EXPANSION VALVE CONTROL (LEV CONTROL) (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening degrees set for each opera- tional frequency of the compressor. However, when any change in indoor/outdoor temperatures or other factors cause air conditioning load fluctuation, the LEV control also works to correct LEV opening degree based on discharge temper- ature (Shell temperature) of the compressor, developing the unit’s performance.
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(2) Time chart Air conditioner OFF (thermostat off) Air conditioner ON Positioning Opening degree is corrected according to discharge Standard Commanded temperature. opening to open degree about 5 minutes <COOL, DRY> Time about 15 minutes <HEAT> OFF Time (3) Control data (a) Reference value of target discharge temperature (COOL/HEAT :) Applied model...
MXZ MICROPROCESSOR CONTROL MXZ-2A30VA MXZ-2A52VA MXZ-4A71VA MXZ-5A100 MXZ-2A40VA MXZ-3A54VA MXZ-4A80VA 12-1. INVERTER SYSTEM CONTROL 12-1-1. Inverter main power supply circuit MXZ-2A30/40/52VA POWER P.C. BOARD INVERTER P.C. BOARD CT61 DB61 Power C63A CT761 supply C63B C63C R64A R64B CT781 TR821 DB65 Booster chopper circucuit Function of main parts SYMBOL...
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12-1-2. Outline of main power supply circuit MXZ-2A30/40/52VA 1. At the start of operation Main power supply circuit is formed when X64 (Relay) is turned ON at compressor startup. To prevent rush current from running into the circuit when power supply is turned ON, R64A and R64B (Current-limitting resistor) are placed in sub circuit.
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MXZ-3A54VA MXZ-4A71/80VA/5A100 1. At the start of operation Main power supply circuit is formed when X64 (Relay) is turned ON at compressor startup. To prevent rush current from running into the circuit when power supply is turned ON, R64A and R64B (Current-limiting resistor) are placed in sub circuit.
DC Motor AC Motor Rotor Permanent magnet is embedded. Excited by magnetic field of stator Rotor Position Signal Necessary Unnecessary w In brushless DC motor, permanent magnet is embedded in the rotor. Therefore, it doesn't require energy to excite the rotor like AC motor does.
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MXZ-3A/4A71/4A80VA The table below shows the role of Exclusive LEV and Receiver LEV in each operation mode. wEvaporation Circulation Discharge High Capacity Pressure Temperature Amount Temperature Distribution Protection Protection Control Protection Exclusive LEV COOL Receiver LEV Exclusive LEV HEAT Receiver LEV Indoor heat Exclusive exchanger...
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• Add opening provided in Difference in Capacity in the table below to the standard opening from 1 to 8, when capacity of the indoor unit is excluding code 1. • Add opening provided in Difference in Operation number in the table below to determined LEV opening for each indoor unit, when 2, 3, 4 or 5 indoor units are operated at the same time.
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MXZ-4A80VA MXZ-5A100VA Exclusive LEV Standard opening (pulse) LEV Opening(code) COOL HEAT Difference in capacity Difference in operation number Code3,4 Code5,6 Code7,8 Code9,10 Code11,12 Code13,14 Code15or above COOL HEAT Receiver LEV Standard opening (pulse) LEV Opening(code) COOL HEAT Difference in operation number operation number COOL HEAT...
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MXZ-3A54VA MXZ-4A71VA Target discharge temperature (:) COOL HEAT Operation frequency 1 unit 2 units 3 units of compressor (Hz) 4 units 1 unit 2 units 3 units 4 units (MXZ-4A71VA) (MXZ-4A71VA) Minimum ~ 23 24 ~ 38 39 ~ 54 55 ~ 69 70 ~ 85 86 ~ 100...
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Correct the LEV opening according to the difference between target discharge temperature and discharge temperature. MXZ-2A30VA MXZ-2A40VA MXZ-2A52VA MXZ-3A54VA MXZ-4A71VA LEV opening correction (pulse) Discharge temperature (:) COOL HEAT More than Target discharge temperature+10 Target discharge temperature+10 to Target discharge temperature+5 Target discharge temperature+5 to Target discharge temperature+2 Target discharge temperature+2 to Target discharge temperature-2 Target discharge temperature-2...
12-3. OPERATIONAL FREQUENCY RANGE MXZ-2A30VA Number of Capacity COOL (Hz) HEAT (Hz) operaing code Min. Max. (Hz) Min. Max. Defrost unit 3, 4 MXZ-2A40VA Number of Capacity COOL (Hz) HEAT (Hz) operating code Min. Max. (Hz) Min. Max. Defrost unit 3, 4 ~ 11 MXZ-2A40VA...
12-5. DISCHARGE TEMPERATURE PROTECTION CONTROL This protection controls the compressor ON/OFF and operation frequency according to temperature of the discharge temperature thermistor. (1) Compressor ON/OFF When temperature of the discharge temperature thermistor exceeds 116:, the control stops the compressor. When temperature of the discharge temperature thermistor is 80: (2A/3A/4A71/4A80VA )/ 100°C (4A80VA /5A) or less, the controls starts the compressor.
12-8. PRE-HEAT CONTROL MXZ-2A MXZ-4A80VA MXZ-5A The compressor is energized even while it is not operating. This is to generate heat at the winding to improve the compressor's start-up condition. Power Compressor Outside temperature 30min. 30min. 30min. 30min. 30min. 30min. 15min.
12-10. DRY OPERATION 1. Thermostat control Thermostat is ON or OFF by difference between room temperature and set temperature. Room temperature minus Room temperature minus set temperature (Initial) set temperature (During operation) Thermostat -1 : or more less than -1 : -0.7 2.
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HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN C C Copyright 2005 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD Distributed in Mar. 2007. No. OBT06 REVISED EDITION-D 7 Distributed in Oct. 2006. No. OBT06 REVISED EDITION-C 7 Distributed in Mar. 2006. No. OBT06 REVISED EDITION-B 7 Distributed in Aug.
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