Mini-split air conditioners typically have excellent cooling and heating capabilities. This may seem paradoxical, but the explanation of how it works is quite simple. All of this has to do with the dual nature of the compressor. It is capable of compressing refrigerant (cooling) as well as expanding refrigerant (heating). By understanding how ductless air conditioners work, you can better operate and maintain them, extending the life of your air conditioning unit.
Components of Ductless Air Conditioners
Before understanding the working principle of the ductless split air conditioner, let’s first understand its main components. The split air conditioner has two main components, indoor unit and outdoor unit.
The indoor unit contains:
1. Evaporator Coil: It is responsible for absorbing the heat from the room’s air and cooling it.
2. Blower: It is responsible for distributing the cool air in the room.
3. Air Filter: It is responsible for cleaning the air before it enters the evaporator coil.
4. Thermostat: It is responsible for setting the temperature of the air conditioner and controlling the indoor unit’s functions.
5. Drain Pan: It collects the condensation from the evaporator coil and sends it through the drainpipe.
The outdoor unit contains:
1. Compressor: It is responsible for compressing and circulating the refrigerant.
2. Condenser Coil: It is responsible for releasing the heat absorbed by the refrigerant into the outdoor air.
3. Fan: It is responsible for blowing air over the condenser coil to increase the heat transfer efficiency.
4. Expansion Valve: It is responsible for decreasing the pressure of the refrigerant before it enters the evaporator coil.
5. Refrigerant Lines: These are copper tubes connecting the indoor and outdoor units and carry the refrigerant between the two units.
How Can A Mini Split Provide Cooling?
The principle of split air conditioners works is the indoor and outdoor units work together to cool the air in a room.
The refrigeration process as follows:
1. The compressor present in the outdoor unit compresses the refrigerant gas, which raises the temperature and pressure of the gas.
2. The highly pressurized and heated refrigerant gas passes through the condenser coils in the outdoor unit where it releases heat into the atmosphere. As a result, the refrigerant gas turns into a high-pressure, high-temperature liquid.
3. The high-pressure, high-temperature liquid refrigerant then passes through the refrigerant lines and enters the indoor unit.
4. In the indoor unit, the liquid refrigerant passes through the expansion valve, where due to a sudden pressure drop, it cools down and turns into a low-pressure liquid, evaporating quickly into a gas.
5. The cool refrigerant gas enters the evaporator coil where it absorbs the heat from the air circulating in the room.
6. The cooled air is then blown back into the room by the indoor unit’s blower.
7. The warm refrigerant gas again passes through the refrigerant lines and enters the outdoor unit to continue the refrigeration cycle.
This process continues until the desired temperature is reached in the room. The split air conditioner constantly monitors the temperature of the room using a thermostat and automatically adjusts the cooling and heating process to maintain the selected temperature setting.
How Can A Mini Split Provide Heating?
Split air conditioners that have a heat pump feature can also provide heating in addition to cooling. The refrigeration cycle works in reverse to achieve heating. The following is how a split air conditioner with a heat pump provides heating:
1. The outdoor unit’s compressor compresses the refrigerant and raises its temperature, which changes the refrigerant from a low-pressure gas to a high-pressure, high-temperature gas.
2. The high-pressure, high-temperature refrigerant then passes through the condenser coil in the outdoor unit, where it releases heat into the atmosphere. As a result, the refrigerant gas turns into a high-pressure, high-temperature liquid.
3. The high-pressure, high-temperature liquid refrigerant then flows through the refrigerant lines and enters the indoor unit.
4. An expansion valve present in the indoor unit reduces the pressure of the refrigerant, causing it to evaporate and cool down rapidly. The refrigerant turns into a low-pressure, low-temperature gas at this stage.
5. The low-temperature refrigerant passes through the indoor unit’s evaporator coil, where it absorbs heat from the air present in the room.
6. The heated gas is then passed through a heat exchanger to transfer heat from the refrigerant to the air of the room supply air.
7. The heated air is distributed throughout the room by the indoor unit’s blower to warm the room.
This cycle continues until the temperature set by the thermostat is reached. The split air conditioner with a heat pump can switch between heating and cooling modes automatically, depending on the temperature set by the thermostat.
