The cooling operation or heating operation does not operate.

CCheck of R.V. coil MUZ-D30/36

Heating operation does not work.

1.Disconnect the lead wire leading to the compressor.

2.3 minutes after turning on the power supply, start EMERGENCY OPERATION in HEAT mode.

Is there voltage of 208 / 230 VAC between pin1

 

and pin 2 at connector CN912?

No

 

Yes

 

 

 

Turn OFF power supply of indoor and outdoor unit.

1.Turn off power supply of indoor and outdoor unit, and discon- nect the connector CN781 in the outdoor electronic control P.C. board.

2.3 minutes after turning ON the power supply, start EMER- GENCY OPERATION in HEAT mode.

Disconnect the connec-

tor CN912 in noise filter No Replace the R.V. coil. P.C. board. Is there normal

resistance to R.V. coil?

Yes

Replace the 4-way valve.

Is there voltage 12 VDC be-

tween the connector CN781 No pin 5 (+) and pin 3 (-)?

Yes

Replace the noise filter P.C. board.

Replace the electronic control P.C. board.

Cooling operation does not work.

1.Disconnect the lead wire leading to the compressor.

2.3 minutes after turning on the power supply, start EMERGENCY OPERATION in COOL mode.

If the connector CN912 is not connected or R.V. coil is open, voltage occurs between terminals even when the control is OFF.

Is there voltage of 208 / 230 VAC between pin1

 

 

 

 

 

Replace the 4-way valve.

and pin 2 at connector CN912?

No

 

 

 

1.Turn OFF power supply of indoor and outdoor unit, and disconnect the connector CN781 in the outdoor electronic control P.C. board.

2.3 minutes after turning ON the power supply, start EMER- GENCY OPERATION in COOL mode.

Is there voltage 12 VDC between the connector

 

 

 

 

 

Replace the noise filter P.C. board.

CN781 pin 5 (+) and pin 3 (-)?

No

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

Replace the outdoor electronic control P.C. board.

30

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Mitsubishi Electronics MUZ-D36NA, MUY-D36NA, U1, MUZ-D30NA Check of R.V. coil MUZ-D30/36, Heating operation does not work

MUY-D36NA, MUZ-D30NA, U1, MUY-D30NA, MUZ-D36NA specifications

Mitsubishi Electronics has long been at the forefront of innovation in heating and cooling solutions, and its latest lineup of multi-zone air conditioning units—MUZ-D36NA, MUY-D30NA, U1, MUZ-D30NA, and MUY-D36NA—reflects this commitment to quality and efficiency. Designed for both residential and commercial applications, these units offer advanced features that enhance comfort and energy savings.

One of the standout characteristics of these models is their energy efficiency. Each unit is equipped with high SEER (Seasonal Energy Efficiency Ratio) ratings, making them ideal for users looking to reduce energy consumption while maintaining optimal indoor climates. The efficiency is complemented by inverter technology, which allows the compressor to adjust its speed based on the cooling demand. This results in a smoother operation, reduced noise levels, and significant energy savings over time.

These units also feature advanced filtration systems that improve indoor air quality. The included high-performance air filters capture dust, allergens, and other particles, ensuring that occupants breathe cleaner air. Additionally, some models are equipped with a plasma filtration system that actively neutralizes odors and airborne contaminants, making them particularly suitable for allergy sufferers.

Mitsubishi's advanced climate control technologies set these models apart. The system can be easily controlled using a user-friendly remote or via a mobile app, offering convenience and flexibility. The intelligent temperature control ensures that rooms are heated or cooled consistently, regardless of external conditions.

Installation versatility is another highlight. These units can be configured for multi-zone systems, allowing for tailored comfort in different spaces. The compact and sleek design makes them suitable for various installations, whether in homes, offices, or retail environments.

Furthermore, the MUZ-D and MUY-D series are equipped with quiet operation features, ensuring minimal disruption in both residential and commercial settings. This is particularly beneficial in spaces where noise could be a concern, such as bedrooms or conference rooms.

In summary, Mitsubishi's MUZ-D36NA, MUY-D30NA, U1, MUZ-D30NA, and MUY-D36NA offer a powerful combination of energy efficiency, advanced filtration, intelligent controls, and quiet operation. These features make them an excellent choice for anyone looking to enhance indoor comfort while minimizing environmental impact. Whether it's for a single room or an entire building, these units are engineered to deliver reliable performance year-round.