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by samatman 1776 days ago
It is in fact thermodynamically and metabolically far easier to heat than to cool.

We're warm-blooded creatures, so if we want to be warmer we can just jump around, or put on insulation. To cool, we have to sweat, and if the sweat can't evaporate much because of high humidity, we have to do a lot of it.

Similarly, if we want to heat a space, we can just burn something. Cooling requires active transport, whether finessed by something like a windcatcher or attic fan, or through an air conditioner.

Heat pumps are more efficient, but more complex, than furnaces, and can be run in reverse to provide air conditioning.
1 comments
amrcnimgrnt 1776 days ago
People really don't appreciate how brutal humidity is on our bodies' ability to cool down.

I run my AC more to dehumidify than to cool. I hate setting my AC below 78, that's freezing, but I have to because of improperly sized AC units, poor HVAC installation, etc.

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balfirevic 1776 days ago
> I hate setting my AC below 78, that's freezing, but I have to because of improperly sized AC units, poor HVAC installation, etc.

How do those influence where you have to set the thermostat?

But indeed, 25 - 25.5 degrees Celsius is just about the most comfortable temperature (summer or winter).

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amrcnimgrnt 1775 days ago
My thermostat is located in a cooler part of my house compared to my bedroom -> my thermostat has to be set to 73 to cool my bedroom to a nice T.

If my AC is very large it wont run very long between cycles. When it does it will wring every bit of moisture out of that relatively small amount of air.

If the AC were smaller, the AC would run just about all day long, more of the air would then go get its moisture removed.

In other words:

1 unit of 4C air mixed with 9 units of 30C air -> 10 units 27.4C. Assuming I've removed all the water in the one unit of 4C air the water content has only gone down 10%

5 units of 24.8 C air mixed with 5 units of 30 C air -> 10 units of 27.4C. If I can get just 50% of the air out chilled 5 units of air, I've removed 25% of the water in the air.

These numbers are just thrown at you, so take them with a BIG grain of salt. You'd have to look at the water saturation tables to really do the math.

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