New section - every question has an answer. Yonatan Shenhav explains difficult topics in science and technology
Answer: Every air conditioner (external and non-central) contains four components: a compressor, a condenser (where the temperature is usually above 70 degrees), an expansion valve (drops the pressure) and an evaporator (where the temperature is about 4 degrees). If you want warm air, put a fan next to the condenser and the air enters a warm room. Modern air conditioners work in a configuration called a heat pump. A heat pump is a super efficient machine that can produce heat or cold with the same components, which simply changes the direction of the thermodynamic cycle.
Now for the question. In a normal heating coil we invest energy in the form of an electric current which creates frictional heat (there is a resistance of metal to the passage of the current through it). This is the most primitive mechanism of heat generation, where the efficiency factor is 1. For every watt invested, we get 1 watt of heating. On the other hand, in a heat pump we will invest energy in compression only. The frozen evaporator (gas flows inside it at 4 degrees Celsius) sitting outside (in winter) absorbs heat from the environment, provided it is at a temperature higher than 4 degrees, and evaporates the cold. That is, the opposite action of pumping heat from a cold environment is performed! After raising the pressure of the gas, our home air conditioner is ready to release the heat stored in it into the living room. That is, the point of a heat pump is to collect the heat from the outside and not produce it. According to Israeli law, the minimum efficiency factor for home air conditioners is 3. In fact, there is no theoretical limit other than the viability of air conditioner companies investing in research into new coolers.
This wonderful efficiency originates from the special materials used by the air conditioners. The requirement for a refrigerator is to be volatile at as low a temperature as possible, so that it can absorb as much heat as possible before evaporation. This heat will come from the room we wish to cool.
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How do you fill 410 gas in a new air conditioner in liquid mode? Or a gas situation?
Heat exchange will only take place from a hot source to a cold source. Even from a cold source to a hot source.
Reply to Weizman: I agree with you completely (except for the absolute bullshit). A zeotropic mixture of R32 40% with 60% R125, like the one used in the huge buildings in Qatar, gives an efficiency of 7. The formula you used is absolutely correct, and since you surely have a background in thermodynamics you know that for a substance that evaporates at a very high temperature with a very high compressor efficiency Massive overcooling can be performed. By using additional inert gas, the material can be heated, and there is no lack of heat for heating. When I said "there is no limit" I was unintentionally wrong. Keep in mind that the most efficient device after a heat pump is a microwave, so it's still a magical machine to me.
If you have to give an answer then you should not be mistaken.
"Actually, there is no theoretical limit (to the efficiency factor) other than the viability of air conditioning companies investing in the research of new coolers."
Absolute bullshit. A heat pump works against the temperature drop (transfers heat from a cold place to a warm place) and therefore must consume energy. The theoretical efficiency is:
Temperature at the place where the heat is pumped (in degrees Kelvin) divided by the temperature difference.
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