Mitsubishi Electric MS-A08ND Quick start guide

SERVICE TECHNICAL GUIDE
Wireless type
Models
MS-A08ND - (WH) · MU-A08ND -
MS-A10ND - (WH) · MU-A10ND -
MS-A12ND - (WH) · MU-A12ND -
MS-A15ND - (WH) · MU-A15ND - C1C1
C1C1
C1C1
C1C1
No. OBT10
SPLIT-TYPE, AIR CONDITIONERS
CONTENTS
MICROPROCESSOR CONTROL
1.“I FEEL CONTROL” OPERATION·································2
2. COOL OPERATION ·······················································5
3. DRY OPERATION ··························································5
4. FAN OPERATION ··························································5
5. FAN MOTOR CONTROL ···············································5
6. AUTO VANE OPERATION·············································5
7. TIMER OPERATION ······················································7
8. EMERGENCY / TEST OPERATION······························7
TM
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MICROPROCESSOR CONTROL
Once the operation mode are set, the same operation mode
can be repeated by simply turning the
OPERATE/STOP(ON/OFF) button ON.
Indoor unit receives the signal with a beep tone.
When the system turns off, compressor will not restart for 3
minutes as 3-minute time delay function operates to protect
compressor from overload.
Signal transmitting section
Operation display section
TEMPERATURE buttons
VANE CONTROL button
TIME SET button
RESET button
FAN SPEED CONTROL button
ECONO COOL button
POWERFUL COOL button
OPERATION SELECT button
TIMER MODE SELECT button
OPERATE/STOP (ON/OFF) button
WIRELESS REMOTE CONTROLLER
MS-A08ND - MS-A10ND - MS-A12ND - MS-A15ND -
MU-A08ND - MU-A10ND - MU-A12ND - MU-A15ND - C1C1C1C1
C1C1C1C1
Lighted
Not lighted
Approx. 2 :
or more
Difference
between target
temperature
and room
temperature
Approx. 2 :
or less
This shows that the
air conditioner is
operating to reach
the target temperature.
Please wait unit the
target temperature is
obtained.
This shows that the
room temperature is
approaching the
target temperature.
Operation stateIndication
Operation Indicator
Operation Indicator lamp
The operation indicator at the right side of the indoor
unit indicates the operation state.
INDOOR UNIT DISPLAY SECTION
• The following indication applies regardless of shape
of the indicator.
●Once the mode is fixed, the mode does not change by
room temperature afterwards.
●Under ON-TIMER ( ) operation, the mode is deter-
mined according to the room temperature at set time the
operation starts.
●When the system is stopped by 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.
1. “I FEEL CONTROL” ()OPERATION
(1) Press OPERATE/STOP(ON/OFF) button on the remote
controller. OPERATION INDICATOR lamp of the indoor
unit turns on with a beep tone.
(2) Select “I FEEL CONTROL”( ) mode with the
OPERATION SELECT button.
(3) The operation mode is determined by the initial room
temperature at start-up of the operation.
Initial room temperature Mode
25°C or more COOL mode of
“I FEEL CONTROL”
DRY mode of
“I FEEL CONTROL”
more than 13°C,
less than 25°C
Operation time chart
Example
Previous operation
COOL mode of
“I FEEL CONTROL”
or COOL mode
Operation time chart
Example
Previous operation
COOL mode of
“I FEEL CONTROL”
or COOL mode
When the system is restarted after 2 hours and
more, the operation mode is determined by the
room temperature at start-up of the operation.
Restart
COOL mode of
“I FEEL CONTROL”
Restart
COOL or DRY mode of
“ I FEEL CONTROL” that
determined by room
temperature at start-up
of the operation.
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2. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button.
In Auto the fan speed is as follows. Initial temperature difference Fan speed
Room temperature minus set temperature : 1.7 degrees or more····························High
Room temperature minus set temperature : Between 1 and 1.7 degrees················Med.
Room temperature minus set temperature : less than 1 degree······························Low
3. Coil frost prevention
① Temperature control
When the indoor coil thermistor RT12 reads 6°C or below 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 6°C, this mode is prolonged until the RT12 reads over 6°C.
(5) TEMPERATURE buttons
In “I FEEL CONTROL”mode, set temperature is decided by the microprocessor based on the room temperature.
In addition, set temperature can be controlled by TOO WARM or TOO COOL buttons when you feel too cool or too warm.
Each time the TOO WARM or TOO COOL button is pressed, the indoor unit receives the signal and emits a beep tone.
● Fuzzy control
When the TOO COOL or TOO WARM button is pressed, the microprocessor changes the set temperature, considering
the room temperature, the frequency of pressing TOO COOL or TOO WARM button and the user’s preference to heat or
cold. So this is called “Fuzzy control”, and works only in “I FEEL CONTROL” mode.
In DRY mode of “I FEEL CONTROL”, the set temperature doesn’t change.
… To raise the set temperature 1 ~ 2 degrees (:)
… To lower the set temperature 1 ~ 2 degrees (:)
TOO
COOL
TOO
WARM
1 deg. 1.7 deg. 3 deg.
Difference between room
temperature and set tem-
perature during operation
(4) The initial set temperature is decided by the initial room temperature.
❈1
Mode Initial room temperature
26°C or more 24°C
Initial room temperature
minus 2 °C
25°C to 26°C
Initial set temperature
DRY mode of
“I FEEL CONTROL”
COOL mode of
“I FEEL CONTROL”
more than13°C, less than 25°C Initial room temperature
minus 2 °C
❈1 When the system is restarted with the remote controller, the system operates with the previous set temperature
regardless of the room temperature at restart.
The set temperature is calculated by the previous set temperature.
-0.3 :0.3 :
1-1. COOL mode of “I FEEL CONTROL”
1. Thermostat control
Thermostat is ON or OFF by difference between room temperature and set temperature
Initial temperature difference Thermostat
Room temperature minus set temperature : 0.3 :or more················································ON
Room temperature minus set temperature : less than -0.3 :············································OFF
Set temperature
Difference between room
temperature and set tem-
perature during operation
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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.
NOTE : By such controls, indoor flow amounts will be reduced in order to lower humidity without much room
temperature decrease.
2. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button .
In Auto fan speed becomes Low.
3. The operation of the compressor and indoor / outdoor fan
Compressor operates by room temperature control and time control.
Set temperature is controlled to fall 2°C from initial room temperature.
Indoor fan and outdoor fan operate in the same cycle as the compressor.
●When the room temperature is 23°C or over:
When the thermostat is ON, the compressor repeats 8 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
●When the room temperature is under 23°C.
When the thermostat is ON, the compressor repeats 2 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
Compressor
Outdoor fan OFF
ON
(Continuously at set speed)
Indoor fan ON
ON
OFF
Operation chart
Example
Operation time chart
Example
Thermostat
Indoor fan
Outdoor fan
Compressor
ON
8 min. 1 min.
3 min. 4 min.
ON
OFFOFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
4. Coil frost prevention
• The operation is the same as coil frost prevention during COOL mode of “I FEEL CONTROL”.
• Indoor fan operates at the set speed and the compressor stops for 5 minutes because coil frost prevention has priority.
When coil frost prevention works while indoor fan’s stop and compressor’s stop, indoor fan operates at set speed.
② Time control
When the three conditions as follows have been satisfied for 1 hour and 45 minutes, compressor stops for 3 minutes.
a. Compressor has been continuously operating.
b. Indoor fan speed is Low or Med..
c. Room temperature is below 26°C.
When compressor stops, the value of its duration measure is reset. When it restarts, its duration measure starts all over
again.
Duration measure temporarily stops when the indoor fan speed becomes High or when room temperature exceeds 26:.
However, it begins to function again when both conditions above, b. and c. are satisfied.
-0.3 :0.3 :
1. Thermostat control
Thermostat is ON or OFF by difference between room temperature and set temperature
Initial temperature difference Thermostat
Room temperature minus set temperature : 0.3 :or more················································ON
Room temperature minus set temperature : less than -0.3 :············································OFF
Set temperature
Difference between room
temperature and set tem-
perature during operation
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High
Med. Low
High
time
Rotational frequency
AUTO
Horizontal Middle Downward Swing
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, which are approximately 12V and transmitted from microprocessor.
(2) The horizontal vane angle and mode change as follows by pressing VANE CONTROL button.
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) Set TEMPERATURE buttons.
Press TOO WARM or TOO COOL button to select the
desired temperature.
The setting range is 16 ~ 31°C.
✻ Indoor fan continues to operate regardless of thermostat’s
OFF-ON at set speed.
✻ Coil frost prevention is the same as COOL mode of
“I FEEL CONTROL”.
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. Set temperature is as
shown in the right chart.
Thermostat does not work.
The other operations are same as DRY mode of
“I FEEL CONTROL”.
(4) DRY operation will not work when the room temperature is
13°C or below.
4. FAN ( )OPERATION
(1) Press OPERATE/STOP(ON/OFF) button. OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select FAN mode with OPERATION SELECT button.
(3) Select the desired fan speed. When AUTO, it becomes Low.
Only indoor fan operates.
Outdoor unit does not operate.
5. 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. With this control, when the fan speed is switched, the
rotational frequency changes smoothly.
(2) Fan motor lock-up protection
When the rotational frequency feedback signal has not output for 12 seconds, (or when the microprocessor cannot
detect the signal for 12 seconds) the fan motor is regarded locked-up. Then the electric current to the fan motor is shut
off. 3 minutes later, the electric current is applied to the fan motor again. During the fan motor lock-up, OPERATION
INDICATOR lamp flashes on and off to show the fan motor abnormality.
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(3) Positioning
The vane is once pressed to the vane stopper below to confirm the standard position and then set to the desired angle.
Confirming of standard position is performed in case of follows.
(a) When OPERATE / STOP(ON/OFF) button is pressed. (POWER ON/OFF)
(b) When the vane control is changed from AUTO to MANUAL.
(c) When SWING is finished.
(d) When the test run starts.
(e) When the power supply turns ON.
(4) VANE AUTO ( ) mode
In VANE AUTO mode, the microprocessor automatically determines the vane angle to make the optimum room-temper-
ature distribution.
1In COOL and DRY operation
2In FAN operation
Vane angle is fixed to Angle 1.
Vane angle is fixed to Angle 4.
(5) STOP (operation OFF) and ON-TIMER standby.
When the following cases occur, the horizontal 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 the ON-TIMER is on standby.
(6) Dew prevention
During COOL or DRY operation at Vane Angle 4 or 5 when the cumulative operation time of compressor exceeds 1
hour, the vane angle automatically changes to Angle 1 for dew prevention.
(7) SWING MODE ( )
By selecting SWING mode with VANE CONTROL button the horizontal vane swings vertically. The remote controller
displays “ ”.
(8) ECONO COOL ( ) operation
When the ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2:higher than that in
COOL mode.
Also the horizontal vane swings in a cycle which fits the temperature of indoor heat exchanger(RT12).
SWING operation makes you feel cooler than set temperature. So, even though the set temperature is higher than that in
COOL mode, the air conditioner can keep comfort. As a result, energy can be saved.
ECONO COOL operation is cancelled when ECONO COOL button is pressed once again or VANE CONTROL button is
pressed or change to other operation mode.
NOTE : ECONO COOL operation does not work in COOL mode of “I FEEL CONTROL”.
SWING operation
When the vane swings in ECONO COOL operation, air blows initially in a horizontal direction.
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.
Also, after 10 minutes when the difference of set temperature and room temperature is more than 2:, the swing opera-
tion is performed in table D~H for more cooling.
The air conditioner repeats the swing operation in various cycle as follows.
Temperature of indoor coil
thermistor RT12 (:)
more than 24°C
5
2
Downward blow time
(sec.)
22°C to 24°C
21°C to 22°C
20°C to 21°C
18°C to 20°C
17°C to 18°C
15°C to 17°C
15°C or less
5
8
11
14
17
20
23
Horizontal blow time
(sec.)
20
17
14
11
8
2
23
A
H
G
F
E
D
C
B
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(9) POWERFUL COOL ( ) mode
When POWERFUL COOL button is pressed in COOL mode, the fan speed and the set temperature are automatically
adjusted.
Operation becomes POWERFUL COOL mode.
POWERFUL COOL mode is automatically released 15 minutes after operation starts, and the operation mode returns to
the mode prior to POWERFUL COOL operation.
POWERFUL COOL mode is also cancelled when POWERFUL COOL button is pressed once again, OPERATE / STOP
(ON/OFF) button is pressed, FAN SPEED CONTROL button is pressed, ECONO COOL button is pressed in COOL
mode, ON-TIMER is set or change to other operation mode.
NOTE1. :TEMPERATURE buttons are not available during POWERFUL COOL operation.
2: VANE CONTROL button is available.
7. TIMER OPERATION
1. How to set the timer
(1) Press OPERATE/STOP (ON/OFF) button to start the air conditioner.
(2) Press TIMER MODE SELECT button ()to select the operation.
“”(OFF TIMER) ➔“”(ON TIMER) ➔TIMER RELEASE
Each time this button is pressed, the timer mode is changed in sequence.
(3) Press TIME SET button ( )to set the timer.
Each time this button is pressed, the set time increases by 1 hour to 12 hours.
NOTE 1 : Be sure to place the remote controller at the position where its signal can reach the air conditioner even during
TIMER operation.
NOTE 2 : Reset the timer in the following cases, or the set time may deviate and other malfunctions may occur.
• A power failure occurs.
• The circuit breaker functions.
NOTE 3 : The OFF TIMER and ON TIMER can not be set at the same time.
TIME
SELECT
(Example 1) Setting to stop the air conditioner 3 hours later.
1 Press “ ” button to select “ ” (OFF TIMER).
2 Press “ ” button to set the “3h”.
TIME
SELECT
3h
7h
(Example 2) Setting to operate the air conditioner 7 hours later.
1 Press “ ” button to select “ ”(ON TIMER).
2 Press “ ” button to set the “7h”.
TIME
SELECT
2. Cancel
Press “ ” button until “ ”(OFF TIMER) and “ ”(ON TIMER) are not displayed.
SELECT
EMERGENCY OPERATION switch
Press once <Cool>
Press again <Stop>
• The following indication applies
regardless of shape of the indicator.
OPERATION INDICATOR lamp
8. 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. The unit will start and OPERATION INDICATOR lamp will light.
The first 30 minutes of operation is the test run operation. This operation is for servicing. Indoor fan runs at High speed
and the unit continues to operate with the thermostat on.
After 30 minutes of test run operation the system shifts to EMERGENCY COOL MODE with a set temperature of 24°C.
The fan speed shifts to Med..
The coil frost prevention works even in emergency operation.
In the test run or emergency operation, the horizontal vane operates in VANE AUTO ( ) mode.
Emergency operation continues until EMERGENCY OPERATION switch is pressed again or the unit receives any signal
from the remote controller. In case of latter normal operation will start.
NOTE : Do not press EMERGENCY OPERATION switch during normal operation.
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HEAD OFFICE: MITSUBISHI DENKI BLDG., 2-2-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN
CCCopyright 2005 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD.
Distributed in May 2005. No.OBT10 7
Made in Japan New publication, effective May 2005
Specifications subject to change without notice.
TM
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