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onelith
July 16th 03, 11:05 PM
Hi,
I would like to hear anybodies experience
with patio or personal water misting devices
that cool you in very hot weather. They look
good but do they work and are they cheap to
operate?
onelith

Nick Pine
July 16th 03, 11:40 PM
onelith > wrote:

> I would like to hear anybodies experience with
>patio or personal water misting devices that
>cool you in very hot weather. They look good but
>do they work and are they cheap to operate?

I'd say they work. You might use one with an outdoor motion detector
light fixture and an old solenoid valve from a washing machine.

Nick

Nick Pine
July 16th 03, 11:40 PM
onelith > wrote:

> I would like to hear anybodies experience with
>patio or personal water misting devices that
>cool you in very hot weather. They look good but
>do they work and are they cheap to operate?

I'd say they work. You might use one with an outdoor motion detector
light fixture and an old solenoid valve from a washing machine.

Nick

The Real Bev
July 17th 03, 02:11 AM
Nick Pine wrote:
>
> onelith > wrote:
>
> > I would like to hear anybodies experience with
> >patio or personal water misting devices that
> >cool you in very hot weather. They look good but
> >do they work and are they cheap to operate?
>
> I'd say they work. You might use one with an outdoor motion detector
> light fixture and an old solenoid valve from a washing machine.

And don't tell the Jehovah's Witnesses about it.

--
Cheers,
Bev
================================================== ============
Everyone crashes. Some get back on. Some don't. Some can't.

The Real Bev
July 17th 03, 02:11 AM
Nick Pine wrote:
>
> onelith > wrote:
>
> > I would like to hear anybodies experience with
> >patio or personal water misting devices that
> >cool you in very hot weather. They look good but
> >do they work and are they cheap to operate?
>
> I'd say they work. You might use one with an outdoor motion detector
> light fixture and an old solenoid valve from a washing machine.

And don't tell the Jehovah's Witnesses about it.

--
Cheers,
Bev
================================================== ============
Everyone crashes. Some get back on. Some don't. Some can't.

Christopher Green
July 17th 03, 05:16 AM
(onelith) wrote in message >...
> Hi,
> I would like to hear anybodies experience
> with patio or personal water misting devices
> that cool you in very hot weather. They look
> good but do they work and are they cheap to
> operate?
> onelith

They are very effective in low-humidity areas. Ones that run off mains
pressure cost next to nothing to operate. If you value cost over
appearance, or you can hide the plumbing with some greenery, garden
mist sprayers cost very little and are as effective as the fancy ones.

--
Chris Green

Christopher Green
July 17th 03, 05:16 AM
(onelith) wrote in message >...
> Hi,
> I would like to hear anybodies experience
> with patio or personal water misting devices
> that cool you in very hot weather. They look
> good but do they work and are they cheap to
> operate?
> onelith

They are very effective in low-humidity areas. Ones that run off mains
pressure cost next to nothing to operate. If you value cost over
appearance, or you can hide the plumbing with some greenery, garden
mist sprayers cost very little and are as effective as the fancy ones.

--
Chris Green

JoelnCaryn
July 17th 03, 09:55 AM
>Hi,
> I would like to hear anybodies experience
>with patio or personal water misting devices
>that cool you in very hot weather. They look
>good but do they work and are they cheap to
>operate?

They work just fine in low humidity areas. In Phoenix, where I live, we tell
people that evaporative cooling stops working as well as air conditioning after
the dewpoint goes over 55F.

They're all over the place here -- outdoor dining patios, the Zoo...

JoelnCaryn
July 17th 03, 09:55 AM
>Hi,
> I would like to hear anybodies experience
>with patio or personal water misting devices
>that cool you in very hot weather. They look
>good but do they work and are they cheap to
>operate?

They work just fine in low humidity areas. In Phoenix, where I live, we tell
people that evaporative cooling stops working as well as air conditioning after
the dewpoint goes over 55F.

They're all over the place here -- outdoor dining patios, the Zoo...

July 17th 03, 04:42 PM
"suzn" > wrote:

>We purchased one to put around the outside edge of our patio cover. They
>did cool down the patio but also made it very wet....
>DH is trying to come up with a way to hang the mist line farther away from
>the patio to avoid everything getting wet.

There is a sudden market for these things in Florida now that smoking is banned
indoors. In a recent newspaper article, a person selling misters to
restaurants mentioned how they have to cycle on and off, with the percentage
depending on the humidity. Nick's idea of a solenoid valve, combined with a
device to regulate it, would seem to be a better solution for you than moving
the line. It wouldn't waste water or leave the area wet.

These misters can reduce AC bills another way. The walls and any concrete
walks surrounding a house can absorb enough heat from sunlight striking them
that they get far above air temperature. Cooling them with a mist can reduce
the AC load. The worse the insulation, the greater the effect. Since many hot
climate houses are CBS with only minimal interior insulation, the reduction in
cooling costs on sunny hot days can be substantial.

July 17th 03, 04:42 PM
"suzn" > wrote:

>We purchased one to put around the outside edge of our patio cover. They
>did cool down the patio but also made it very wet....
>DH is trying to come up with a way to hang the mist line farther away from
>the patio to avoid everything getting wet.

There is a sudden market for these things in Florida now that smoking is banned
indoors. In a recent newspaper article, a person selling misters to
restaurants mentioned how they have to cycle on and off, with the percentage
depending on the humidity. Nick's idea of a solenoid valve, combined with a
device to regulate it, would seem to be a better solution for you than moving
the line. It wouldn't waste water or leave the area wet.

These misters can reduce AC bills another way. The walls and any concrete
walks surrounding a house can absorb enough heat from sunlight striking them
that they get far above air temperature. Cooling them with a mist can reduce
the AC load. The worse the insulation, the greater the effect. Since many hot
climate houses are CBS with only minimal interior insulation, the reduction in
cooling costs on sunny hot days can be substantial.

Christopher Green
July 17th 03, 08:58 PM
The Real Bev > wrote in message >...
> Christopher Green wrote:
> >
> > (onelith) wrote in message >...
> > > Hi,
> > > I would like to hear anybodies experience
> > > with patio or personal water misting devices
> > > that cool you in very hot weather. They look
> > > good but do they work and are they cheap to
> > > operate?
> > > onelith
> >
> > They are very effective in low-humidity areas. Ones that run off mains
> > pressure cost next to nothing to operate. If you value cost over
> > appearance, or you can hide the plumbing with some greenery, garden
> > mist sprayers cost very little and are as effective as the fancy ones.
>
> They use misters and fans to cool off the people standing in line at Magic
> Mountain (really hot and really dry). They don't use anywhere near enough
> of them, but they work beautifully.

Lots of public places in SoCal (and, I'd guess, Arizona) do this now.
So long as the weather stays bone-dry (until the monsoons hit in
Arizona, anyway), it's a very good thing. They get much less effective
on the occasional humid day.

--
Chris Green

Christopher Green
July 17th 03, 08:58 PM
The Real Bev > wrote in message >...
> Christopher Green wrote:
> >
> > (onelith) wrote in message >...
> > > Hi,
> > > I would like to hear anybodies experience
> > > with patio or personal water misting devices
> > > that cool you in very hot weather. They look
> > > good but do they work and are they cheap to
> > > operate?
> > > onelith
> >
> > They are very effective in low-humidity areas. Ones that run off mains
> > pressure cost next to nothing to operate. If you value cost over
> > appearance, or you can hide the plumbing with some greenery, garden
> > mist sprayers cost very little and are as effective as the fancy ones.
>
> They use misters and fans to cool off the people standing in line at Magic
> Mountain (really hot and really dry). They don't use anywhere near enough
> of them, but they work beautifully.

Lots of public places in SoCal (and, I'd guess, Arizona) do this now.
So long as the weather stays bone-dry (until the monsoons hit in
Arizona, anyway), it's a very good thing. They get much less effective
on the occasional humid day.

--
Chris Green

The Real Bev
July 17th 03, 11:18 PM
Fritz M wrote:
>
> The Real Bev > wrote:
>
> > And don't tell the Jehovah's Witnesses about it.
>
> I'm missing an obscure reference to something here, so I'll bite:
>
> Why not?

Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

--
Cheers,
Bev
*----------------------------------------------------*
*Are you *sure* there's a hyphen in "anal-retentive?"*

The Real Bev
July 17th 03, 11:18 PM
Fritz M wrote:
>
> The Real Bev > wrote:
>
> > And don't tell the Jehovah's Witnesses about it.
>
> I'm missing an obscure reference to something here, so I'll bite:
>
> Why not?

Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

--
Cheers,
Bev
*----------------------------------------------------*
*Are you *sure* there's a hyphen in "anal-retentive?"*

Chloe
July 18th 03, 12:10 AM
"The Real Bev" > wrote in message
...
> Fritz M wrote:
> >
> > The Real Bev > wrote:
> >
> > > And don't tell the Jehovah's Witnesses about it.
> >
> > I'm missing an obscure reference to something here, so I'll bite:
> >
> > Why not?
>
> Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

Heh. We've similarly enjoyed surprising the neighbor's grandkids who even
with parental supervision--or perhaps with parental encouragement--come
right on over and play in our yard. That sprinkler system, it's on a
timer, y'know, and we just "can't" keep the darn thing from coming on.

Chloe
July 18th 03, 12:10 AM
"The Real Bev" > wrote in message
...
> Fritz M wrote:
> >
> > The Real Bev > wrote:
> >
> > > And don't tell the Jehovah's Witnesses about it.
> >
> > I'm missing an obscure reference to something here, so I'll bite:
> >
> > Why not?
>
> Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

Heh. We've similarly enjoyed surprising the neighbor's grandkids who even
with parental supervision--or perhaps with parental encouragement--come
right on over and play in our yard. That sprinkler system, it's on a
timer, y'know, and we just "can't" keep the darn thing from coming on.

Fritz M
July 18th 03, 01:23 AM
The Real Bev > wrote:

> Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

*LOL*

I was trying to think of something complicated, like if there was a
religious requirement against getting wet while selling magazines or
something.

RFM
--
To reply, translate domain from l33+ 2p33|< to alpha.
4=a 0=o 3=e +=t

Fritz M
July 18th 03, 01:23 AM
The Real Bev > wrote:

> Water spray. Motion sensor. Unwary JWs. Frugal entertainment.

*LOL*

I was trying to think of something complicated, like if there was a
religious requirement against getting wet while selling magazines or
something.

RFM
--
To reply, translate domain from l33+ 2p33|< to alpha.
4=a 0=o 3=e +=t

Nick Pine
July 18th 03, 12:40 PM
> wrote:

>There is a sudden market for these things in Florida now that smoking
>is banned indoors. In a recent newspaper article, a person selling
>misters to restaurants mentioned how they have to cycle on and off,
>with the percentage depending on the humidity...

How would that work, for maximum comfort, given an outdoor temp and RH and
CFM of outdoor airflow through a building? The ASHRAE comfort zone is roughly
a rectangle from 68 to 79 F and humidity ratio w = 0.0045 to 0.012, with
maximum comfort in the center. The lower left corner is cool, the upper
right is warm, and one might say the "constant comfort" line runs from
the upper left to the lower right.

Nick

Nick Pine
July 18th 03, 12:40 PM
> wrote:

>There is a sudden market for these things in Florida now that smoking
>is banned indoors. In a recent newspaper article, a person selling
>misters to restaurants mentioned how they have to cycle on and off,
>with the percentage depending on the humidity...

How would that work, for maximum comfort, given an outdoor temp and RH and
CFM of outdoor airflow through a building? The ASHRAE comfort zone is roughly
a rectangle from 68 to 79 F and humidity ratio w = 0.0045 to 0.012, with
maximum comfort in the center. The lower left corner is cool, the upper
right is warm, and one might say the "constant comfort" line runs from
the upper left to the lower right.

Nick

Don and Shelly
July 18th 03, 02:14 PM
DH is a mailman in FL and uses a personal mister during the summer as
there is no air in mail trucks. He says it helps somewhat.

Don and Shelly
July 18th 03, 02:14 PM
DH is a mailman in FL and uses a personal mister during the summer as
there is no air in mail trucks. He says it helps somewhat.

July 18th 03, 03:27 PM
(Nick Pine) wrote:

> wrote:
>
>>There is a sudden market for these things in Florida now that smoking
>>is banned indoors. In a recent newspaper article, a person selling
>>misters to restaurants mentioned how they have to cycle on and off,
>>with the percentage depending on the humidity...
>
>How would that work, for maximum comfort, given an outdoor temp and RH and
>CFM of outdoor airflow through a building? The ASHRAE comfort zone is roughly
>a rectangle from 68 to 79 F and humidity ratio w = 0.0045 to 0.012, with
>maximum comfort in the center. The lower left corner is cool, the upper
>right is warm, and one might say the "constant comfort" line runs from
>the upper left to the lower right.
>
>Nick

I'm not sure how the things are set. The smokers obviously don't want their
tobacco doused, but yet want to be as cool as possible. I am guessing that
some sort of humidity and heat detection are fed into a program, perhaps
including wind speed as a factor. Even a small improvement in comfort is
enough to make some people happy.

July 18th 03, 03:27 PM
(Nick Pine) wrote:

> wrote:
>
>>There is a sudden market for these things in Florida now that smoking
>>is banned indoors. In a recent newspaper article, a person selling
>>misters to restaurants mentioned how they have to cycle on and off,
>>with the percentage depending on the humidity...
>
>How would that work, for maximum comfort, given an outdoor temp and RH and
>CFM of outdoor airflow through a building? The ASHRAE comfort zone is roughly
>a rectangle from 68 to 79 F and humidity ratio w = 0.0045 to 0.012, with
>maximum comfort in the center. The lower left corner is cool, the upper
>right is warm, and one might say the "constant comfort" line runs from
>the upper left to the lower right.
>
>Nick

I'm not sure how the things are set. The smokers obviously don't want their
tobacco doused, but yet want to be as cool as possible. I am guessing that
some sort of humidity and heat detection are fed into a program, perhaps
including wind speed as a factor. Even a small improvement in comfort is
enough to make some people happy.

Nick Pine
July 18th 03, 04:06 PM
> wrote:

>>>There is a sudden market for these things in Florida now that smoking
>>>is banned indoors. In a recent newspaper article, a person selling
>>>misters to restaurants mentioned how they have to cycle on and off,
>>>with the percentage depending on the humidity...

>>How would that work, for maximum comfort...?

>I'm not sure how the things are set. The smokers obviously don't want their
>tobacco doused, but yet want to be as cool as possible. I am guessing that
>some sort of humidity and heat detection are fed into a program, perhaps
>including wind speed as a factor. Even a small improvement in comfort is
>enough to make some people happy.

Maybe they mist until annoying and water-wasting puddles appear...

Or try for "optimum comfort." ASHRAE standard humings rate comfort from
Y = +3 (hot) to 0 (neutral) to -3 (cold.) Studies on 1600 college-age
students produced this equation: Y = 0.135t+1.92p-11.122, where t is
the (F) temp and p is the (psi) vapor pressure of water in air.

NREL says the long-term average daily max for Phoenix in June is 103.5 F
(or maybe more, with recent heat islanding) with humidity ratio w = 0.0056
pounds of water per pound of dry air, which makes p = 14.696/(0.62198/w+1)
= 0.131 psi (0.267 "Hg) and Y = 0.135x103.5+1.92x0.131-11.122 = 3.1 (hot.)
At 100% RH, the vapor pressure of 103.5 F air is e^17.863-9621/(460+103.5))
= 2.202 "Hg, and 0.267/2.202 = 0.12, so the RH is 12%.

But the dew point is only 9621/(17.863-ln(0.267))-460 = 41.5 F... cold.

For "optimum comfort," Y = 0 = 0.135t+1.92p-11.122, ie t + 14.22p = 82.39.
Evaporating a pound of water takes about 1000 Btu, and the specific heat of
air is about 0.24 Btu/lb-F, so adding water makes t = 103.5-4167(w-0.0056),
approximately, which makes 103.5-4167w+23.34+208.8/(0.62198/w+1) = 82.39,
ie w = 0.01158, after some algebra, which makes t = 78.6 F, with a 55% RH.

Nick

Nick Pine
July 18th 03, 04:06 PM
> wrote:

>>>There is a sudden market for these things in Florida now that smoking
>>>is banned indoors. In a recent newspaper article, a person selling
>>>misters to restaurants mentioned how they have to cycle on and off,
>>>with the percentage depending on the humidity...

>>How would that work, for maximum comfort...?

>I'm not sure how the things are set. The smokers obviously don't want their
>tobacco doused, but yet want to be as cool as possible. I am guessing that
>some sort of humidity and heat detection are fed into a program, perhaps
>including wind speed as a factor. Even a small improvement in comfort is
>enough to make some people happy.

Maybe they mist until annoying and water-wasting puddles appear...

Or try for "optimum comfort." ASHRAE standard humings rate comfort from
Y = +3 (hot) to 0 (neutral) to -3 (cold.) Studies on 1600 college-age
students produced this equation: Y = 0.135t+1.92p-11.122, where t is
the (F) temp and p is the (psi) vapor pressure of water in air.

NREL says the long-term average daily max for Phoenix in June is 103.5 F
(or maybe more, with recent heat islanding) with humidity ratio w = 0.0056
pounds of water per pound of dry air, which makes p = 14.696/(0.62198/w+1)
= 0.131 psi (0.267 "Hg) and Y = 0.135x103.5+1.92x0.131-11.122 = 3.1 (hot.)
At 100% RH, the vapor pressure of 103.5 F air is e^17.863-9621/(460+103.5))
= 2.202 "Hg, and 0.267/2.202 = 0.12, so the RH is 12%.

But the dew point is only 9621/(17.863-ln(0.267))-460 = 41.5 F... cold.

For "optimum comfort," Y = 0 = 0.135t+1.92p-11.122, ie t + 14.22p = 82.39.
Evaporating a pound of water takes about 1000 Btu, and the specific heat of
air is about 0.24 Btu/lb-F, so adding water makes t = 103.5-4167(w-0.0056),
approximately, which makes 103.5-4167w+23.34+208.8/(0.62198/w+1) = 82.39,
ie w = 0.01158, after some algebra, which makes t = 78.6 F, with a 55% RH.

Nick

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