Air conditioner and controlling method thereof

An air conditioner comprising:

• an indoor unit housing;
• an indoor heat exchanger configured to exchange heat with air introduced into the indoor unit housing;
• a first blower fan located in the indoor unit housing and configured to blow heat-exchanged air out of the indoor unit housing;
• a second blower fan located in the indoor unit housing at a higher position than the first blower fan, and configured to blow heat-exchanged air out of the indoor unit housing;
• a third blower fan located in the indoor unit housing at a higher position than the second blower fan and configured to blow heat-exchanged air out of the indoor unit housing;
• and
• a processor configured to:
• adjust a rotational speed of the first blower fan, a rotational speed of the second blower fan, and a rotational speed of the third blower fan so that, during a heating operation of the air conditioner,
• the rotational speed of the first blower fan is higher than the rotational speed of the second blower fan and higher than the rotational speed of the third blower fan, and
• the rotational speed of the second blower fan is lower than the rotational speed of the third blower fan while the rotational speed of the first blower fan is maintained at a rotational speed that is higher than the rotational speed of the second blower fan and higher than the rotational speed of the third blower fan, and
• adjust the rotational speed of the first blower fan, the rotational speed of the second blower fan, and the rotational speed of the third blower fan so that, during a cooling operation of the air conditioner,
• the rotational speed of the third blower fan is higher than the rotational speed of the second blower fan and higher than the rotational speed of the first blower fan, and
• the rotational speed of the first blower fan is lower or higher than the rotational speed of the second blower fan while the rotational speed of the third blower fan is higher than the rotational speed of the second blower fan and higher than the rotational speed of the first blower fan.

A method of controlling an air conditioner that includes an indoor unit housing, an indoor heat exchanger configured to exchange heat with air flowing into the indoor unit housing, a compressor configured to compress a refrigerant for a cooling operation or a heating operation performed by the air conditioner, a first blower fan located in indoor unit housing and configured to blow heat-exchanged air out of the indoor unit housing, a second blower fan located in the indoor unit housing at a higher position than the first blower fan and configured to blow heat-exchanged air out of the indoor unit housing, and a third blower fan located in the indoor unit housing at a higher position than the second blower fan and configured to blow heat-exchanged air out of the indoor unit housing, the method comprising:

• adjusting a rotational speed of the first blower fan, a rotational speed of the second blower fan, and a rotational speed of the third blower fan so that, during the heating operation,
• the rotational speed of the first blower fan is higher than the rotational speed of the second blower fan and higher than the rotational speed of the third blower fan, and
• the rotational speed of the second blower fan is lower than the rotational speed of the third blower fan while the rotational speed of the first blower fan is maintained at a rotational speed that is higher than the rotational speed of the second blower fan and higher than the rotational speed of the third blower fan.