After stopping the operation of the air conditioner, turn off the power supply switch and remove the power plug. When repairing or inspecting the circuit must be done without turning off the power, take great care not to touch live parts. The correct coolant is specified in the manuals and on the specification labels supplied with our products.
We will not be held responsible for mechanical faults, system malfunctions, unit breakdowns or accidents caused by failure to follow the instructions. Connecting the following models to the MUZ-EF·VE(H) series outdoor units enables the low standby power control. The following models can be connected to the MUZ-EF·VE(H) series after being connected to the MXZ series once and operated, for example due to relocation.
In this case, the MUZ-EF·VE(H) series outdoor units will not operate without taking a step. Nano platinum filter) Air cleaning filter (electrostatic anti-allergy enzyme filter, option).
NOISE CRITERIA CURVES4
OBH589G
Unit: mm
OUTLINES AND DIMENSIONS5
WIRING DIAGRAM6
REFRIGERANT SYSTEM DIAGRAM7
SERVICE FUNCTIONS8
8-4. AUTO RESTART FUNCTION
Operation
WIRELESS REMOTE CONTROLLER
MICROPROCESSOR CONTROL9
Coil frost prevention
The operating frequency of the compressor is controlled by the temperature of the indoor heat exchanger to prevent the coil from freezing. When the temperature of the indoor heat exchanger becomes too low, spiral frost prevention mode works.
Low outside temperature operation
Indoor fan speed control
9-2. DRY ( ) OPERATION
9-4. HEAT ( ) OPERATION
- Cold air prevention control
- High pressure protection
- Defrosting
- How to set the time
- To release the timer
When you try to operate 2 or more indoor units at the same time with one outdoor unit, one for cooling and the other for heating, the operation mode of the indoor unit that operates first will be selected. Other indoor units cannot operate and the operation indicator light flashes as shown in the figure below. When the indoor unit starts to operate while the outdoor unit is defrosting, it takes a few minutes (max. 10 minutes) to blow out the warm air.
Although the indoor unit that does not work may become hot or the sound of refrigerant flowing, they may not malfunction during heating. The motor's direction of rotation, speed and angle are controlled by pulse signals (approx. 12 V) sent from the indoor microprocessor. Confirmation of default position is performed in the following cases:. a) When the operation starts or ends (including timer operation).
In VANE AUTO mode, the microprocessor automatically determines the angle of the vane to make the optimal distribution of room temperature. Initially "0:00" flashes on the TIME MONITOR current time display, so set the current time correctly with the CLOCK SET button. How to set the current time (a) Press the set time button. b) Press the TIME SET ( and ) buttons to set the current time.
Each press of the BACK button ( ) increases the set time by 1 minute and each press of the BACK button ( ) decreases the set time by 1 minute. Set the timer time with the TIME SET ( and ) buttons. a) During operation, press the OFF TIMER button ( ). Each press of the BACK button ( ) increases the set time by 10 minutes: each press of the BACK button ( ) decreases the set time by 10 minutes.
PROGRAM TIMER
9-8. WEEKLY TIMER OPERATION
- How to set the weekly timer
- Checking weekly timer setting Checking weekly timer setting
- How to cancel operation
- Before troubleshooting, check the following 1) Check the power supply voltage
- Take care of the following during servicing
- Troubleshooting procedure
- How to replace batteries
When setting the timer for more than one day of the week or one number, the button should not be pressed for each setting. Press the button to enter the weekly timer setting mode and hold the button for 5 seconds to clear all the weekly timer settings. When the weekly timer is ON, the day of the week will be lit, the timer setting is complete.
When all days of the week are selected to view settings and another setting is included between them, it will be displayed. Emergency operation is available when the remote control is missing or has failed, or the batteries in the remote control are running low. The indoor fan runs at high speed and the temperature control does not work.
In the test run or emergency operation, the horizontal vane operates in VANE AUTO ( ) mode. Emergency operation continues until EMERGENCY OPERATION switch is pressed once or twice or the unit receives any signal from the remote control. When the system turns OFF, compressor will not restart for 3 minutes as the 3-minute time delay function works to protect compressor from overload.
TROUBLESHOOTING10
10-2. FAILURE MODE RECALL FUNCTION Outline of the function
Flow chart of failure mode recall function for the indoor/outdoor unit
Room temperature thermistor short or open circuit is detected every 8 seconds during operation. Refer to the characteristics of the main internal coil thermistor, internal coil thermistor (10-7.). 2.5 seconds OFF Serial signal The serial signal from the external unit is not received for a maximum of 6 minutes.
The rotation frequency feedback signal is not output for the 12 seconds after the indoor fan motor is driven.
10-3. INSTRUCTION OF TROUBLESHOOTING
When the indoor unit started operating and detected the following state abnormality (first detection after ON), the indoor fan motor turns OFF and the OPERATION INDICATOR lamp flashes. The indoor unit is connected to the low power standby model after it is connected to the low power standby model once. It happens three times in a row that the compressor stops within 1 minute after start-up due to over-current protection or start-up fault protection.
Confirm the deviation in detail using the outdoor unit failure mode recall function. NOTE: The indoor unit may be connected to an outdoor unit that does not have low standby power. To use a low standby power model, clear the error history by referring to "Deleting the Stored Abnormal Condition" described in 10-2.1.
If the operation indicator lamp continues to flash as shown in No.1 after the procedure, refer to 10-6. The operation mode of each indoor unit is set differently to Cooling (includes HEAT) and Heating at the same time, the operation mode of the indoor unit that was operated at the beginning takes priority.
10-5. TROUBLE CRITERION OF MAIN PARTS
10-6. TROUBLESHOOTING FLOW
B Check of remote controller and indoor electronic control P.C. board Check if the remote controller is exclusive for this air conditioner
Connect the tester to the fan motor clutch lead wire, and “-” to lead wire, otherwise the resistance cannot be measured properly. D How to check wrong wiring and serial signal error MUZ-EF Type Turn the main power supply.
D How to check miswiring and serial signal error MUZ-EF Type Turn the main power supply
Is there any misconnection, poor contact or wire disconnection of the indoor/outdoor connecting wire. No (On or off). board or external electronic control P.C. Be careful of the residual voltage of the smoothing capacitor. Is there 10 to 20 V DC amplitude between internal terminal block S2 and S3. lt;Serial signal confirmation>.
If there is an error in the indoor/outdoor connection cable:. such as wire damage, interconnection and/or poor contact with the terminal block, replace the indoor/.
E Electromagnetic noise enters into TV sets or radios
10-7. TEST POINT DIAGRAM AND VOLTAGE
Indoor electronic control P.C. board
Receiver board
Display board
Switch board
Removing the panel
DISASSEMBLY INSTRUCTIONS11
OPERATING PROCEDURE PHOTOS/FIGURES
Remove the indoor electrical box
Removing the nozzle assembly
Removing the horizontal vane motor (1) Remove the nozzle assembly (Refer to 4.)
Removing the indoor fan motor, the indoor coil thermistor and the line flow fan
Fixing the indoor coil thermistor
NOTE
Holder shapeClip shape
Position and procedure for mounting the clip-shape part
