Mitsubishi Electric MSZ-AY Air Conditioners

When the unit is stopped, the AIR PURIFYING lamp blinks twice. This indicates that the interlock switch for the air purifying device is not functioning correctly, often because the front panel is not firmly closed.

When the AIR PURIFYING lamp blinks 2 times, it indicates an error with the air purifying device. The air purifying operation will not be conducted.

The AIR PURIFYING lamp continuously blinks during an AIR PURIFYING power operation check, or if the air purifying device is wet after cleaning. This indicates that protection is active due to dirt, moisture, or a device malfunction.

When the AIR PURIFYING lamp continuously blinks, it indicates that the AIR PURIFYING power control circuit on the indoor electronic control P.C. board is malfunctioning. As a result, the air purifying operation will not be conducted.

The air conditioner has entered coil frost prevention mode because the indoor heat exchanger temperature became too low. During this mode, the compressor temporarily stops, but the indoor fan continues to operate at the set speed.

The indoor unit displays error code E1, indicating a general operational malfunction within the Mitsubishi Electric MSZ-AY Air Conditioners system. This code usually points to an internal issue that prevents normal operation.

Your Mitsubishi Electric MSZ-AY Air Conditioner displays error code ER1, indicating that an internal fault has been detected within the system, which could affect its ability to operate correctly.

The air conditioner has initiated low outside temperature operation. In this mode, the outdoor fan's speed is reduced or it stops entirely when the outdoor temperature drops to a certain level.

The indoor unit's operation indicator lamp is off. This means the air conditioner is in standby mode, particularly when part of a multi-system setup, and is not actively running.

The indoor unit and outdoor unit do not operate because the serial signal from the outdoor unit has not been received for 6 minutes. This can also happen if a non-low-standby-power outdoor unit was previously connected, and a low-standby-power model is now in use. It can also be caused by miswiring or interference.

The indoor unit's upper lamp blinks 14 or more times, indicating a general abnormality that isn't covered by other specific blink patterns. This could include issues with indoor thermistors, defrost thermistor, or ambient temperature thermistor.

The indoor unit's upper lamp blinks twice, indicating an issue with either the indoor coil thermistor or the room temperature thermistor. The thermistor might be short-circuited or have an open circuit.

The indoor unit's upper lamp blinks three times, indicating that the rotational frequency feedback signal is not being emitted during indoor fan operation. This suggests a problem with the indoor fan motor.

The indoor unit's upper lamp blinks four times, indicating that the system cannot properly read data from the nonvolatile memory on the indoor electronic control P.C. board. This suggests an issue with the main control board.

The indoor unit's upper lamp blinks five times. This occurs when the compressor stops three times consecutively due to overcurrent protection or startup failure protection within one minute of starting. This indicates an issue with the outdoor power system.

The indoor unit's upper lamp blinks six times, indicating that the outdoor thermistors (temperature sensors) are either short-circuited or have an open circuit during compressor operation.

The indoor unit's upper lamp blinks seven times, indicating that the system cannot properly read data from the nonvolatile memory of the inverter P.C. board or the outdoor electronic control P.C. board. This suggests an issue with the outdoor unit's main control boards.

The indoor unit's upper lamp lights up continuously (solid), and the outdoor unit does not operate. This indicates that data in the nonvolatile memory of the inverter P.C. board or the outdoor electronic control P.C. board cannot be properly read.

If your indoor unit was previously connected to an MXZ series outdoor unit and then relocated and connected to a MUZ-AY series outdoor unit, the MUZ-AY outdoor unit may not operate correctly. This is because a memorized abnormal condition from the previous setup needs to be cleared.

In AIR PURIFYING power failure mode recall function, if the indoor POWER lamp blinks one time, it indicates an issue where the voltage between CN1T1 (+) and (GND) on the electronic P.C. board falls below 1.3V (spark discharge judgment voltage). This suggests a problem with the AIR PURIFYING power control.

In AIR PURIFYING power failure mode recall function, if the indoor POWER lamp blinks two times, it indicates an electrode spark discharge error. This occurs when the voltage between CN1T1 (+) and (GND) on the electronic P.C. board falls by 1.2V below the normal voltage value (2.5V).

In AIR PURIFYING power failure mode recall function, if the indoor POWER lamp blinks three times, it indicates an abnormal electric discharge error. This happens when the voltage between CN1T1 (+) and (GND) on the electronic P.C. board rises above 3V.

In AIR PURIFYING power failure mode recall function, if the indoor POWER lamp blinks four times, it indicates an issue where the voltage between CN1T1 (+) and (GND) on the electronic P.C. board falls significantly (0.4V / 0.5ms).

In AIR PURIFYING power failure mode recall function, if the indoor POWER lamp blinks five times, it indicates an abnormal electric discharge error where the AIR PURIFYING power cannot be turned OFF even when the operation is turned OFF with the remote controller.

When you activate the AIR PURIFYING power failure mode recall function, the indoor POWER lamp blinks at 0.5-second intervals, accompanied by a beep. This indicates an abnormality in the air purifying device.

The indoor unit of your Mitsubishi Electric MSZ-AY Air Conditioner displays error code SC1. This typically signifies a problem with communication within the air conditioning system, potentially between the indoor and outdoor units or internal components.

In failure mode recall function, if the upper OPERATION INDICATOR lamp blinks one time every 0.5 seconds, it indicates a short or open circuit in the room temperature thermistor. This error is detected every 8 seconds during operation.

In failure mode recall function, if the upper OPERATION INDICATOR lamp blinks eleven times with a 2.5-second OFF interval, it indicates that the rotational frequency feedback signal from the indoor fan motor was not emitted for 12 seconds after the motor started.

In failure mode recall function, if the upper OPERATION INDICATOR lamp blinks twelve times with a 2.5-second OFF interval, it indicates that the indoor control system cannot properly read data from the nonvolatile memory of the indoor electronic control P.C. board.

The upper lamp on the indoor unit blinks 14 or more times. This indicates a general or unspecified abnormality in the outdoor unit, which could stem from various issues including thermistor problems.

The upper lamp on the indoor unit blinks 2 times. This indicates a problem with either the room temperature thermistor or the indoor coil thermistor, which measure temperatures for proper operation.

In failure mode recall function, if the upper OPERATION INDICATOR lamp blinks two times with a 2.5-second OFF interval, it indicates a short or open circuit in the indoor coil thermistor. This error is detected every 8 seconds during operation.

The upper lamp on the indoor unit blinks 3 times. This indicates a problem with the indoor fan motor, which circulates air within the room.

In failure mode recall function, if the upper OPERATION INDICATOR lamp blinks three times with a 2.5-second OFF interval, it indicates that the serial signal from the outdoor unit has not been received for a maximum of 6 minutes.

The upper lamp on the indoor unit blinks 4 times. This indicates a problem with the indoor unit's control system, possibly related to its electronic control board.

The upper lamp on the indoor unit blinks 5 times. This indicates an abnormality in the outdoor unit's power system, potentially affecting components like the inverter or compressor.

The upper lamp on the indoor unit blinks 6 times. This indicates a problem with a thermistor located in the outdoor unit, which measures temperatures crucial for efficient operation.

The upper lamp on the indoor unit blinks 7 times. This indicates a problem with the outdoor unit's control system, potentially involving the inverter P.C. board or the main outdoor electronic control P.C. board.

The upper lamp on the indoor unit blinks on and off rapidly at 0.5-second intervals. This indicates a potential miswiring issue or trouble with the serial signal communication between the indoor and outdoor units.

When you activate the failure mode recall function, if the upper lamp on the indoor unit stays ON for 3 seconds without a beep, and then starts blinking at 0.5-second intervals, it indicates an abnormality in the outdoor unit.

When you activate the failure mode recall function, if the upper lamp on the indoor unit stays ON for 3 seconds with an accompanying beep, and then starts blinking at 0.5-second intervals, it indicates an abnormality in the indoor unit.

The upper lamp on the indoor unit's OPERATION INDICATOR blinks rapidly at 0.5-second intervals, accompanied by a beep. This indicates that either the indoor or outdoor unit is experiencing an abnormal condition.

The Wi-Fi interface LED blinks 5 times, indicating that the connection to the router failed. This can happen in either WPS-PUSH or Access Point mode due to various reasons like communication distance, router settings, or incorrect setup steps.