Re: Door Locks & Defoggers ?
 

In article <B9dXl.31747$YU2.31210@nlpi066.nbdc.sbc.com>,
"Paul" <pkmueller@sbcglobal.net> wrote:

> > The cool temperature of the air is secondary to the fact that the
> > moisture is removed. It's the removal of moisture, and that your body's
> > evaporative cooling mechanism is allowed to work, that makes you
> > comfortable.
>
> So, driving through Death Valley at noon on a July day with the windows open
> to let in plenty of that dry air, we'd be cool and comfortable, correct?

Cooler than with the windows closed, yes.

Of *course* cool air is part of the equation--but it's not the primary
part.

Re: Door Locks & Defoggers ?
 

Elmo P. Shagnasty wrote:
> In article <Xns9C24B84723805jyanikkuanet@74.209.136.86>,
> Jim Yanik <jyanik@abuse.gov> wrote:
>
>> BTW,the air conditioning system is a HEAT transfer device;
>> it works by moving -heat- from one area to another.
>>
>> moisture removal is secondary,a side benefit.
>
> No, moisture removal--necessary for the body's evaporative cooling
> mechanism to work--is the primary goal.
>
> To remove moisture, one uses the concept of condensation--which requires
> a cool surface to move the moist air over.


sorry dude, it's the other way around. you can dry air without cooling
it. you can't cool it without condensation. moisture removal is simply
an artifact of cooling. thermodynamics.

Re: Door Locks & Defoggers ?
 

On 2009-06-08, Jim Yanik <jyanik@abuse.gov> wrote:
> "Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in
> news:elmop-417AD4.12560908062009@mara100-84.onlink.net:
>
>> In article <Xns9C2456ACB1ED3jyanikkuanet@74.209.136.83>,
>> Jim Yanik <jyanik@abuse.gov> wrote:
>>
>>> IMO,the intent of AC is to provide cool air,and the removal of
>>> moisture is only a secondary effect of providing cool air.(IOW,I
>>> think you're wrong)
>>
>> Cool air in and of itself is meaningless to the human body.
>
> wrong. ambient temperature DOES matter to the body.
> THAT is what makes one sweat,not how much humidity is present.
>
>> The
>> body's cooling mechanism depends on its ability to evaporate
>> moisture--and if you have very damp air, if the dew point is low, then
>> the moisture your body emits as a cooling mechanism has nowhere to go.
>> If the moisture can't evaporate, the body can't shed heat nearly well
>> enough.
>>
>> Certainly you've had those days where the air is quite cool, but
>> there's a bunch of moisture; it's quite uncomfortable, isn't it?
>
> not as uncomfortable as a hot interior of a auto,at 100-140 degF or even
> more,despite how dry it might be.
>>
>> The point of A/C is to provide an environment where the body's
>> evaporative cooling mechanism can work.
>>
>>
>>
>>
>>> That is what makes you comfortable.(and keeps you from sweating
>>> heavily)
>>
>> The cool temperature of the air is secondary to the fact that the
>> moisture is removed. It's the removal of moisture, and that your
>> body's evaporative cooling mechanism is allowed to work, that makes
>> you comfortable.
>>
>
> wrong.
> the purpose of auto AC is to remove heat from the interior of the auto.
> moisture content doesn't matter in that respect.
>
> the heat is what makes a person perspire. not the humidity.
> if the air temp inside is 110 degF,it doesn't matter to the human body if
> the humidity is only 10%.
>

Both are somewhat true, though the temp is a bit more important, IMO.

If the humidity is high, when you sweat, it does not evaporate, and
therefore does nothing to lower your body temp. That is why it seems
more uncomfortable to be in Southern Florida at 100 F than in Arizona
at the same temp. BUT, so long as the temp is 100 F, you're going to
be hot, and no amount of de-humidifying is going to change that.
And in a car, the temp will be even higher.

Therefore, you need cool air to reduce the temp, and some measure of
de-humidification, especially in very humid climates, to help your
body cool itself.

Also, the warmer air is, the higher a percentage of absolute humidity
it can hold. 70 degree air simply holds less moisture than 100 degree
air does. If you can lower the temp on the inside of the vehicle, it
will be less humid by definition...


--
Joe - Linux User #449481/Ubuntu User #19733
joe at hits - buffalo dot com
"Hate is baggage, life is too short to go around pissed off all the
time..." - Danny, American History X

Re: Door Locks & Defoggers ?
 

In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
jim beam <me@privacy.net> wrote:

> you can dry air without cooling
> it.

how?

Re: Door Locks & Defoggers ?
 

"Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in news:elmop-
D1C527.07554009062009@mara100-84.onlink.net:

> In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
> jim beam <me@privacy.net> wrote:
>
>> you can dry air without cooling
>> it.
>
> how?
>

stuff that absorbs moisture;hygroscopic materials. like silica gel.

--
Jim Yanik
jyanik
at
kua.net

Re: Door Locks & Defoggers ?
 

"Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in news:elmop-
9328E6.19311508062009@mara100-84.onlink.net:

> In article <Xns9C24B84723805jyanikkuanet@74.209.136.86>,
> Jim Yanik <jyanik@abuse.gov> wrote:
>
>> BTW,the air conditioning system is a HEAT transfer device;
>> it works by moving -heat- from one area to another.
>>
>> moisture removal is secondary,a side benefit.
>
> No, moisture removal--necessary for the body's evaporative cooling
> mechanism to work--is the primary goal.

except the other guy's mention of Death Valley being very dry and very hot
shows you're wrong.

Auto AC is for removal of heat from the interior,moisture removal
is secondary.

>
> To remove moisture, one uses the concept of condensation--which requires
> a cool surface to move the moist air over.


--
Jim Yanik
jyanik
at
kua.net

Re: Door Locks & Defoggers ?
 

"Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in
news:elmop-BBD1F9.19320808062009@mara100-84.onlink.net:

> In article <B9dXl.31747$YU2.31210@nlpi066.nbdc.sbc.com>,
> "Paul" <pkmueller@sbcglobal.net> wrote:
>
>> > The cool temperature of the air is secondary to the fact that the
>> > moisture is removed. It's the removal of moisture, and that your
>> > body's evaporative cooling mechanism is allowed to work, that makes
>> > you comfortable.
>>
>> So, driving through Death Valley at noon on a July day with the
>> windows open to let in plenty of that dry air, we'd be cool and
>> comfortable, correct?
>
> Cooler than with the windows closed, yes.

but not comfortable. and not much cooler.

sweating heavily in the 100plus -dry- desert heat still does not make a
person comfortable. But the cool air of AC removes that heat and allows
comfort.
>
> Of *course* cool air is part of the equation--but it's not the primary
> part.
>

Yes,it is.
AC is primarily a HEAT transfer device.
It's not specifically designed to remove humidity,but to remove HEAT.

--
Jim Yanik
jyanik
at
kua.net

Re: Door Locks & Defoggers ?
 

In article <Xns9C2553BBF10A4jyanikkuanet@74.209.136.83>,
Jim Yanik <jyanik@abuse.gov> wrote:

> > Of *course* cool air is part of the equation--but it's not the primary
> > part.
> >
>
> Yes,it is.

OK, fine. Consider this the next time it's a nice, cool, 63 degrees
outside--and 100% relative humidity.

And ask yourself why the hell you are dying to turn on the A/C.

Re: Door Locks & Defoggers ?
 

In article <Xns9C2552892B5A0jyanikkuanet@74.209.136.83>,
Jim Yanik <jyanik@abuse.gov> wrote:

> "Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in news:elmop-
> D1C527.07554009062009@mara100-84.onlink.net:
>
> > In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
> > jim beam <me@privacy.net> wrote:
> >
> >> you can dry air without cooling
> >> it.
> >
> > how?
> >
>
> stuff that absorbs moisture;hygroscopic materials. like silica gel.

so.....you have an air conditioner in your car and/or home that's full
of hygroscopic materials?

My question to jim was, in the context of this conversation, how are you
removing moisture without condensing it onto a cooler surface?

Re: Door Locks & Defoggers ?
 

Elmo P. Shagnasty wrote:
> In article <Xns9C2552892B5A0jyanikkuanet@74.209.136.83>,
> Jim Yanik <jyanik@abuse.gov> wrote:
>
>> "Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in news:elmop-
>> D1C527.07554009062009@mara100-84.onlink.net:
>>
>>> In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
>>> jim beam <me@privacy.net> wrote:
>>>
>>>> you can dry air without cooling
>>>> it.
>>> how?
>>>
>> stuff that absorbs moisture;hygroscopic materials. like silica gel.
>
> so.....you have an air conditioner in your car and/or home that's full
> of hygroscopic materials?
>
> My question to jim was, in the context of this conversation, how are you
> removing moisture without condensing it onto a cooler surface?

you could do it with pressure changes - moisture condensation is always
a problem in paint shops and there's no significant temp change in air
lines there - unlike a/c systems.

i appreciate that you think dehumidification is a great thing, and maybe
it is a side-benefit of having a/c, but the objective of the equipment
is not to simply dehumidify. if it were, it wouldn't go to the trouble
and expense of venting waste heat to the outside of the vehicle, it
would be used to re-heat the dehumidified air inside the car and thus
save on componentry and energy.

Re: Door Locks & Defoggers ?
 

Elmo P. Shagnasty wrote:
> In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
> jim beam <me@privacy.net> wrote:
>
>> you can dry air without cooling
>> it.
>
> how?


Seriously? Ok. By *heating it*.

Re: Door Locks & Defoggers ?
 

"Elmo P. Shagnasty" <elmop@nastydesigns.com> wrote in news:elmop-
1B71E5.20484809062009@mara100-84.onlink.net:

> In article <Xns9C2553BBF10A4jyanikkuanet@74.209.136.83>,
> Jim Yanik <jyanik@abuse.gov> wrote:
>
>> > Of *course* cool air is part of the equation--but it's not the primary
>> > part.
>> >
>>
>> Yes,it is.
>
> OK, fine. Consider this the next time it's a nice, cool, 63 degrees
> outside--and 100% relative humidity.


Consider Death Valley;100 plus heat and DRY air.
Yet you still need to remove the HEAT from your auto to be
comfortable,rather than just use the fan to pull in dry outside air that's
around 120 degF.
To repeat,AC is a HEAT transfer device,and you have to remove the
interior heat to be comfortable.

>
> And ask yourself why the hell you are dying to turn on the A/C.
>

few people use their auto AC in such temps.
such a use is SECONDARY to the primary purpose of -removing HEAT- from an
auto interior.


I live in central FLORIDA,and I know all about humidity,and about hot cars.

--
Jim Yanik
jyanik
at
kua.net

Re: Door Locks & Defoggers ?
 

In article <fLFXl.33375$VL5.15396@newsfe22.iad>, Leftie <No@Thanks.net>
wrote:

> Elmo P. Shagnasty wrote:
> > In article <seidneyJ0MWjVLDXnZ2dnUVZ_qydnZ2d@speakeasy.net> ,
> > jim beam <me@privacy.net> wrote:
> >
> >> you can dry air without cooling
> >> it.
> >
> > how?
>
>
> Seriously? Ok. By *heating it*.

In the context of this conversation? Seriously?

But I thought you wanted COOL air.

And you don't remove moisture by heating. You change the dew point, but
you don't remove moisture.

Condensation removes moisture.

Re: Door Locks & Defoggers ?
 

Jim Yanik wrote:
>
> few people use their auto AC in such temps.

"Few People" Man you need to get out more. Using the A/C in the winter
months when there is snow and ice clears the windows of condensation so
quickly.

> such a use is SECONDARY to the primary purpose of -removing HEAT- from an
> auto interior.

Removing the humidity is part of removing the heat from a vehicle or
building.

Re: Door Locks & Defoggers ?
 

Brian Smith wrote:
> Jim Yanik wrote:
>>
>> few people use their auto AC in such temps.
>
> "Few People" Man you need to get out more. Using the A/C in the
> winter months when there is snow and ice clears the windows of
> condensation so quickly.
>
>> such a use is SECONDARY to the primary purpose of -removing HEAT- from
>> an auto interior.
>
> Removing the humidity is part of removing the heat from a vehicle
> or building.
>

technically, it's not. if you simply want to dehumidify, you don't
bother pumping the heat outside.