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out_of_protocol

just pulled typical split-system listing in my country:

Gree Lomo Arctic R32 Inverter 2022 , about €740 (this is one of the top makers)

energy used while cooling: 0.7kW

energy used while heating: 0.7kW

cooling power: 2.7kW

heating power: 3kW

4x efficiency, yay! that's what heat pumps do

outside temperature from +43C to -25C. i've seen -30C and +48C in some models

Also, installation for split units is cheap around here

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Split units in the US tend to be crazy expensive. When I was shopping for an AC, it was definitely a few thousand more than a regular (central) AC. I know folks in other countries buy it all the time, so it must be cheaper there.

"Cooling" and "heating" just means the inside coil is colder/warmer than the outside, it does not mean the inside temperature will be comfortable for everyone. Neither while cooling nor while heating.

Could you please explain what you mean? Split system in question is air-air, heat transfers between blocks via special liquid, and warmer /colder air spread through a room via fan. There are no coils. Also, keeping comfortable temperature inside is function of heat loss via walls/windows and effective power of cooling/heating

The special liquid is running through a system of tubes, called "coils" so it could exchange heat with the air. Keeping comfortable temperatures inside is also a function of the inside coil's temperature, which depends on the special liquid and the compressor. The higher temperature difference between the inside and outside coils, the higher compression is required and lower is the COP. Incidentally, the high inside coil's temperature is also required to heat the air inside at a reasonable rate.

technically speaking, you can crank up internal fan speed to eleven and get exhaust temperature slightly above current room temperature even if internals are way too hot. regular resistive heaters do that, with their heating elements fired up way past boiling water temperature

The problem is not the exhaust being too hot, but the heating element being too cold. Gas furnace, for example, burns gas at temperatures much higher than that of boiling water.

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