In a pool situation....does latent evaporation absorb sensible?

[Rhizzlebop]

I posted about this over in the commercial thread and noone seems to be seeing it. Or maybe my post is too long to read and follow.

My mail question is this.

When you have an indoor therapy pool at 90F and air at 85F and water evaporates and creates a latent load, does that absorb sensible heat (such as from windows and walls) so that when looking at your total load there is an added latent load and a sensible credit where dry heat is absorbed by the moisture?

I'm having trouble making sure my unit selection covers the loads.

Heres a link to the other thread.

http://hvac-talk.com/vbb/showthread.php?t=668311

[genduct]

Your theory is basically correct. The evaporation process does, theoretically have the liquid (surface) drop to wet bulb temp, Ala swamp coolers BUT the real problem is the equipment has a limited ability ( by design) to remove latent load. It's called the SHf sensible heat factor and 25% is the nominal latent capacity, So your pool, or restaurants or any place with a high people load (sweat) are an application challenge.

Chilled water with your ability to get a deeper coil with more latent is the typical choice or using a bypass of hot gas to reheat is also a possibility

[Rhizzlebop]

In this case, I have selected a unit from PoolPak. It is for pool rooms like this.

It was selected based on air and water temps and pool surface area. These usually drive the unit size.

When the submittal came in, I'm finding that while Poolpak says it'll handle the pool area, and the total load seems ok, it is short on sensible.

See, the selection i got months ago from poolpak didn't actually indicate a sensible capacity. It simple stated a latent capacity in terms of lb/hr removal, and then gave a total capacity in MBH.

When the submittal came it was broken down further and gave a sensible in MBH.

that sensible is SHORT of my load AT the rated lb/hr moisture removal. In reality, we wont face that much latent, so we should get MORE sensible capacity at LESS latent.

However, their selection software wont let them enter less latent and see what the sensible rises to.

It also doesn't account for latent absorbing sensible as I think it actually does. In that case, my sensible load is less than I think it is.

[kevinnn]

From what I can remember, and please verify what I am saying because it may or may not be correct. The water evaporating from the pool takes the sensible heat from the water to evaporate. An AC system would first dehumidify ,removing heat in the moisture in the air which would turn into condensation on the cold AC coil. Then it would start to bring down the sensible heat in the pool room. I believe it actually occurs at the same time ( latent and sensible reduction ) but since there is so much more heat in the latent load the AC coil is taxed with the heat in the steam where once that is removed it will start to reduce the sensible load.