Many years back, I learnt about how air-conditioning work. It basically works by transferring heat through conduction from the cooling fins to the air outside of the room/house/unit that it is supposed to cool.
Outside air < — Cooling fins <— metal tubes <— freon gas <— internal air (from room etc)
In the process, some heat is generated. This heat generated is due to inefficiency of the compressor, electronics etc found in air-conditioning units. This inefficiency is common in practically *all* electrical devices, where some electrical power is converted into actual intended work, while others are lost, either as heat, sound or kinetic energy or a combination of them all.
In a sense, air-conditioners do not create “coolness”. “Cold” cannot be created. Only heat can be created. Coldness appears to exist only in contrast to the lack or relative differences in heat. So while a heater generates heat, a cooler (eg air-con) do not actually create cold. It merely displaces it. Coldness itself is also empty of inherent characteristic.
Further to that, heaters do not actually generate or create heat as well. They merely release the potential energy “trapped” or “stored” in the fuel, or convert energy from one form to another, eg convert electrical energy to heat energy. In the process, most heaters “loose” some energy through ambient heating (ie, heating up the appliant itself in an unintended manner), unintended lighting, sound etc. We can perhaps say that heat itself is dependent arising, that it is also inherently empty.