A reverse cycle air conditioner works like a heat pump, moving heat either into or out of a room to heat or cool it, respectively. It essentially "reverses" the refrigeration cycle to switch between heating and cooling.
Here's a breakdown of how it works:
1. The Refrigerant:
- A special fluid called refrigerant circulates throughout the system. This refrigerant has properties that allow it to absorb and release heat efficiently.
2. Cooling Mode:
- Evaporation: Inside the indoor unit, the refrigerant absorbs heat from the room air, turning it from a liquid into a gas (evaporation). This process cools the air, which is then blown back into the room.
- Compression: The gaseous refrigerant then travels to the compressor (usually located in the outdoor unit), where it is compressed. This increases its temperature and pressure.
- Condensation: The hot, high-pressure refrigerant flows through the condenser (also in the outdoor unit). Here, it releases its heat to the outside air, turning back into a liquid (condensation).
- Expansion: The liquid refrigerant passes through an expansion valve, which reduces its pressure and temperature. It then returns to the indoor unit to begin the cycle again.
3. Heating Mode (Reversed Cycle):
- The key to a reverse cycle air conditioner is a reversing valve. When switched to heating mode, this valve changes the direction of the refrigerant flow.
- Evaporation: The refrigerant now absorbs heat from the outside air (even when it's cold outside), turning it into a gas. It's important to note that even cold air contains some heat energy.
- Compression: The compressor still compresses the gaseous refrigerant, increasing its temperature and pressure.
- Condensation: The hot, high-pressure refrigerant now flows to the indoor unit, where it releases its heat into the room, turning back into a liquid. This warms the air that is blown into the room.
- Expansion: The liquid refrigerant then passes through the expansion valve, reducing its pressure and temperature before returning to the outdoor unit to continue the cycle.
4. Key Components:
- Refrigerant: The working fluid that carries heat.
- Compressor: Compresses the refrigerant, increasing its temperature and pressure.
- Condenser: Releases heat from the refrigerant to the outside (cooling mode) or inside (heating mode).
- Evaporator: Absorbs heat from the inside (cooling mode) or outside (heating mode), causing the refrigerant to evaporate.
- Expansion Valve: Reduces the pressure and temperature of the refrigerant.
- Reversing Valve: Directs the refrigerant flow to switch between heating and cooling modes.
- Fans: Circulate air over the condenser and evaporator coils to facilitate heat transfer.
In Summary: A reverse cycle air conditioner uses a refrigerant to absorb and release heat, moving it from one location to another. By reversing the flow of the refrigerant, the system can either cool or heat a room.
