Emergency Operation, SW4 | Mitsubishi Electronics PUZ-A18NHA2

10-8. EMERGENCY OPERATION

(1)When the error codes shown below are displayed on outdoor unit or microcomputer for wired remote controller or indoor unit has a failure, but no other problems are found, emergency operation will be available by setting the emergency opera- tion switch (SWE) to ON and short-circuiting the connector (CN31) on outdoor controller board.

●When following abnormalities occur, emergency operation will be available.

Error code	Inspected content

U4	Open/short of pipe thermistor (TH3/TH6)

E8	Indoor/outdoor unit communication error •Signal receiving error (Outdoor unit)

E9	Indoor/outdoor unit communication error •Transmitting error (Indoor unit)

E0 ~ E7	Communication error other than outdoor unit
Ed	Communicaiton error between outdoor controller board and M-NET board (Serial communication error)

(2)Check the following items and cautions for emergency operation

1Make sure that there is no abnormality in outdoor unit other than the above abnormalities. (Emergency operation will not be available when error codes other than the above are indicated.)

2For emergency operation, it is necessary to set the emergency operation switch (SWE) on indoor controller board. Refer to the electrical wiring diagram of indoor unit for how to set the indoor unit.)

3During emergency operation, the air-conditioner will continuously be operated by supplying power and stopping it: It can not be turned on or off by remote control, and temperature control is not possible.

4Do not perform emergency heating operation for an extended period of time: If the outdoor unit starts defrosting during this period, cold air will blow out from the indoor unit.

5Do not perform emergency cooling operation for more than 10 hours: Neglecting this could result in freezing the heat exchanger in indoor unit.

(3)Emergency operation procedure

1Turn the main power supply off.

2Turn on the emergency operation switch (SWE) on indoor controller board.

3Set the shorting pins of emergency operation connector (CN31) on outdoor controller board to ON.

4Use SW4-2 on outdoor controller board to set the operation mode (cooling or heating). (SW4-1 is not used.)

SW4		CN31	Shorting pins
	Heating	ON
ON

1 2 Cooling OFF

5Turning the main power supply on will start the emergency operation.

(4)Releasing emergency operation

1Turn the main power supply off.

2Set the emergency operation switch (SWE) on indoor controller board to OFF.

3Set the shorting pins of emergency operation connector (CN31) on outdoor controller board to OFF.

4Set SW4-2 on outdoor controller board as shown in the right.

wIf shorting pins are not set on emergency operation connector (CN31), the setting remains OFF.

SW4

1 2

Heating (PUZ only)

Cooling

PUZ-A36NHA2-BS, PUY-A12NHA2, PUY-A42NHA2-BS, PUY-A30NHA2, PUZ-A36NHA2 specifications

Mitsubishi Electronics has long been a leader in the HVAC industry, and their range of air conditioning units, including the PUY-A24NHA2, PUZ-A24NHA2, PUY-A24NHA2-BS, PUZ-A42NHA2-BS, and PUY-A42NHA2, exemplifies their commitment to innovation and energy efficiency. These models are designed to provide optimal climate control for both residential and commercial applications, ensuring comfort throughout the year.

One of the defining features of these models is their advanced inverter technology, which allows for precise temperature control and reduced energy consumption. The inverter technology adjusts the compressor speed according to the cooling load, significantly lowering operating costs compared to traditional fixed-speed systems. This means that users can enjoy consistent comfort without worrying about surging energy bills.

The PUY and PUZ units come equipped with powerful indoor and outdoor components that enable efficient heat exchange. These systems provide excellent performance even in extreme weather conditions, with reliable operation at low ambient temperatures. This capability ensures that you can maintain a comfortable environment, no matter the season.

Additionally, the models are designed with quiet operation in mind. The outdoor units incorporate noise-reduction technology, ensuring that the systems operate at minimal sound levels. This is especially beneficial for residential areas or office environments, where maintaining a peaceful atmosphere is crucial.

Mitsubishi Electronics has also integrated smart technology into these units. With options for remote control via Wi-Fi, users can manage their air conditioning settings from anywhere, using their smartphones or tablets. This integration enhances user convenience and allows for more efficient scheduling and energy management.

These models are also known for their environmentally friendly refrigerants, such as R410A, which contribute to lower global warming potential and align with modern sustainability practices. By choosing Mitsubishi's PUY and PUZ series, consumers not only prioritize their comfort but also contribute to environmental conservation.

In summary, the Mitsubishi Electronics PUY-A24NHA2, PUZ-A24NHA2, PUY-A24NHA2-BS, PUZ-A42NHA2-BS, and PUY-A42NHA2 air conditioning units are equipped with cutting-edge technology, offering energy efficiency, quiet operation, and smart functionality. Whether for residential or commercial use, these units are designed to meet the demands of modern climate control while prioritizing energy savings and sustainability.