12mo ago

Wait, not like that

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Yet I have never seen a food refrigerator called a heat pump. Air-to-air always seems to be called AC to differentiate it from the air-to-water the UK government wants to push.
- I never see refrigerators being called AC either, and they're air-to-air heat pumps too. People just call things what they want regardless of the technical details.
  
  The actual technology is called refrigeration. We should really be calling them all refrigerators, including AC, heat pumps, whatever. AC is a specific application of the refrigeration cycle, and so is a heat pump.
  
  Pointless discussion, but they're all heat pumps. Refrigeration cycle is the name of the physical process. Most heat pumps make use of that thermodynamic principle, but there are some niche ones that don't. But people don't care about that, and so find it more useful to call them by what their purpose is, and that varies locally.
  
  Actually that's wrong. When we build food refrigerators using peltier modules, it's still a refrigerator. The reverse carnot cycle is just one type of refrigeration cycle, reverse rankine and reverse brayton cycles still count.
  Sure you could call them all heat pumps, and you might be technically right. Nobody actually calls them that though. Most people probably haven't figured out that an AC unit, a heat pump, and a food refrigerator are all actually the same concept in different dressing and sizes.
  It's only an irrelevant topic if you can actually communicate clearly, which is actually very hard as almost no one understands this stuff. Especially in the UK where this is all viewed as newfangled, expensive, and unreliable technology. To be fair they aren't wrong in this country: the way we handle, specify, and install ASHPs makes them feel and act inferior to a good old condensing gas boiler. It's a sad state of affairs.
  
  I was referring to electrocaloric, and Stirling engine heat pumps.
  
  There are currently no production heat pumps using the electrocaloric effect to my knowledge. Stirling engine I doubt as well. Either way still classes as refrigeration. In fact a Stirling engine heat pump/refrigerator would still need refrigerant as it needs a working fluid.
  Edit: also pretty sure a Stirling engine is an implementation of a carnot engine
- Because at some point society decided to call them refrigerators or AC. The thing *inside the refrigerator or air conditioner" that makes it work is called a "heat pump" -- that's the unambiguous name of the device. Just like the bit inside a car that provides motive force is called the "engine" or the "motor".
  The device that uses a heat pump to both heat and cool a building is actually called an Air source heat pump, but since that's a mouthful most people simply call it a "heat pump" to distinguish it from traditional AC that only works to cool an area. Sure, maybe you get that odd area the calls it something different (my region calls soft drinks "pop") but that's not the norm.
  
  Round here we call that bit the compressor, as in "Need a new fridge/AC unit.. compressor's broke." The term generally encompasses the compressor and the condenser, even though they are separate bits witch, together make a "heat pump." I've never heard it called a heat pump in that context though (USA).
  
  Nope you can have AHSPs that only heat. The Wikipedia article even says so.

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