On Monday, February 9, 2015 at 8:47:58 AM UTC-5, trader_4 wrote:

The water it came from can't be reheated and reevaporated, because it went down the drain (at least in my house I have the basement dehumidifier piped to the drain).


We were talking about an ideal, closed, perfectly insulated room, not
your house.


Doesn't matter. The water can sit in the humidifier reservoir in the room forever. Re-evaporating that water is the ONLY way to lose the 6.1 kWthr heat gained from condensing that water. That heat was gained from the phase change of the water, not from changing the temperature of the air or water.. That's why it is so large, roughly equal to the mechanical energy added. That heat stays in the room but is transferred from the water to the air. So technically yes, it was in the room all along, but it was trapped in the roughly 1% of air that is water vapor not in the 99% rest of the air.

It is a good thing it is not an ideal closed perfectly insulated room. If it were, assuming a 20x30x8 room, and if I did the math right (you are welcome to check it) the temperature rise from the electrical energy used would be 160 degrees and from the water condensed, 150 degrees.

On Monday, February 9, 2015 at 10:17:51 AM UTC-5, TimR wrote:
On Monday, February 9, 2015 at 8:47:58 AM UTC-5, trader_4 wrote:

The water it came from can't be reheated and reevaporated, because it went down the drain (at least in my house I have the basement dehumidifier piped to the drain).


We were talking about an ideal, closed, perfectly insulated room, not
your house.


Doesn't matter. The water can sit in the humidifier reservoir in the room forever.

Well it does matter. If the water sits in the humififier reservoir, you
have a *closed* system. Then, the only heat added to the room is from
the electricity consumed. If the water goes out of the room, then you
have an array of complex situations to consider.


Re-evaporating that water is the ONLY way to lose the 6.1 kWthr heat gained from condensing that water. That heat was gained from the phase change of the water, not from changing the temperature of the air or water. That's why it is so large, roughly equal to the mechanical energy added. That heat stays in the room but is transferred from the water to the air.

There you go again, conflating heat with temperature.


So technically yes, it was in the room all along, but it was trapped in the roughly 1% of air that is water vapor not in the 99% rest of the air.

It is a good thing it is not an ideal closed perfectly insulated room. If it were, assuming a 20x30x8 room, and if I did the math right (you are welcome to check it) the temperature rise from the electrical energy used would be 160 degrees and from the water condensed, 150 degrees.

Temp rise and heat are two different things, capiche?