On Wed, 20 Sep 2006 20:23:41 -0400, "Solar Flare"
wrote:

Hot water huymidification techniques increase germ breeding and are
not recommended for sinus problems anymore. Welcome to the 90's

There is no germ breeding, the vapor is steam,
the water is fresh from the tap every day with ample
clorine, and I don't think I have a sinus problem,
I do have a dry air problem if I don't humidify
when the outside temperature is below 40 F.

I also think I would have even more of a problem
if I had a forced air furnace which could raise temperatures
fast, the baseboard heat is not able to catch up very quickly
if I let it get behind.

Joe Fischer

Hi Joe;

Joe Fischer wrote:

"Stormin Mormon" wrote:

And what effect did that have, insulating the
thermometer by wrapping the bulb with dry cotton?
Seems like it would read the temperature much
faster if the bulb wasn't insulated.

Sorry, I didn't say the cotton was dry, it may have
been wet with water or even alcohol, I am not a
trained weather man. :-)

In all likelihood it was water.
The instrument most use is called a "Sling Psychrometer".
http://en.wikipedia.org/wiki/Sling_psychrometer

I assume he was checking dew point, but I am not
certain.

Actually he was measuring what is called "Wet Bulb
Temperature". Along with the "Dry Bulb" or ambient
temperature the relative humidity can be calculated.

Dew point temperature is always lower than wet bulb.
Wet bulb is basically the cooling effect and is
dependent on the relative humidity.

Moist air is lighter than dry air, so dew point was
important in several ways for Army Air Force weather
forecasting.

Sure, dew point is another method to measure relative
humidity.

Joe Fischer

Duane

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The medical people disagree with you. The heated water vapour is a
breeding ground for bacteria and virii. Not recomended for treatment
of sinus, ear or cold infections. Cold water humidifiers are
recommended but they leave deposits of dust everywhere.

"Joe Fischer" wrote in message
...
On Wed, 20 Sep 2006 20:23:41 -0400, "Solar Flare"
wrote:

Hot water huymidification techniques increase germ breeding and are
not recommended for sinus problems anymore. Welcome to the 90's

There is no germ breeding, the vapor is steam,
the water is fresh from the tap every day with ample
clorine, and I don't think I have a sinus problem,
I do have a dry air problem if I don't humidify
when the outside temperature is below 40 F.

I also think I would have even more of a problem
if I had a forced air furnace which could raise temperatures
fast, the baseboard heat is not able to catch up very quickly
if I let it get behind.

Joe Fischer

Joe Fischer wrote:

Try your math on adding enough water to maintain
constant 50 percent relative humidity to change 10,000 cubic
feet of air every two hours (with zero people in the house).

No thanks. ASHRAE says houses need 15 cfm per occupant, so
zero people need zero cfm.

Nick

Eeyore wrote:

Airitght houses are very unhealthy.

Au contraire, current thinking is "build it tight, and ventilate it right."

Some Canadian houses are extremely airitght, and very healthy.

Nick

wrote:
Eeyore wrote:


Airitght houses are very unhealthy.


Au contraire, current thinking is "build it tight, and ventilate it right."

Some Canadian houses are extremely airitght, and very healthy.

Nick


Yes, very airtight, with controlled, heat exchanged ventilation HRV,
with ERVs recommended.

Get them very tight to minimize heat gain/loss as appropriate, and
introduce outside air at controlled rates with minimal loss of heated
(or cooled) air.

Energy savings of 30-40% are documented in Canada

wrote:

I know someone who has a house that is so airtight that it came with an air
exchanger. Crazy..

An exhaust fan with a 60% humidistat is cheaper. Latent heat may be worth
exchanging. Even air-leaky houses need ventilation on mild days...

Nick

Solar Flare wrote:

I doubt the cool air came from ducts on the roof without powered
ventilation.

"Joe Fischer" wrote:

...With a large crowd, the heat generated per person increased
the natural convection out those top windows, drawing air in
the hidden floor ducts.

All we need is a difference in bouyancy, ie a column of indoor air
that is warmer and/or moister than the column of outdoor air.

Nick

Robert Gammon wrote:

Some Canadian houses are extremely airitght, and very healthy.

Yes, very airtight, with controlled, heat exchanged ventilation HRV,
with ERVs recommended.

HRVs are not required by law in every part of Canada. Some of those
airtight houses just have exhaust fans, eg R2000 houses in Ontario.
Exhaust fans waste more energy than HRVs and ERVs, but the amount of
energy isn't large, and it may not matter in a solar-heated house :-)

OTOH, the legal requirement for HRVs on Minnesota's air-leaky houses
seems to be a successful lobbying effort and a serious waste of money.

Nick

On Wed, 20 Sep 2006 12:58:04 -0400, Joe Fischer
wrote:

On Wed, wmbjk wrote:

sigh http://www.mayoclinic.com/health/com...056/DSECTION=3

I didn't say that germs are not involved, in fact,
I said germs are involved

"Involved" eh? Previously you wrote that "there may be colds that are
caught, but mine come from inflamed sinus irritated by dry air." So
here's your opportunity to make your opinion clear - do you believe
that you can catch a cold *without* exposure to a virus?

Fifty percent relativity is just an easy to
maintain number, possibly in a clean house
any constant relative humidity that does not
irritate the sensitive nasal or airway passages
would do as well. (Constant RH!)

RH here this morning is 2%, but it can shift quickly and wildly during
monsoon season (just ending). According to your theory, we should be
afflicted by colds constantly. How do you explain the fact that we go
years between colds?

Your advice reminds me of the self-titled country doctor who claimed a
miracle cure for the common cold. When a patient complained that he
still had the cold after a few days, the "doctor" told him the cure
takes at least a week.

Wayne

wrote:
wrote:


I know someone who has a house that is so airtight that it came with an air
exchanger. Crazy..


An exhaust fan with a 60% humidistat is cheaper. Latent heat may be worth
exchanging. Even air-leaky houses need ventilation on mild days...

Nick


Canada says all new houses there should be equipped with an air to air
heat exchanger that ventilate the house several times a day (I forget
the actual spec)

If the outside air temp is -20F, you want to introduce as little of that
as possible to the house. Air to air heat exchangers will raise that
incoming temp quite a bit by cooling off the outgoing air.

Nope not as cheapas Nick's solution, but our Northern neighbors have
much more severe winters than most of us in the USA experience.

Even Washington state mandates a ventilation system in all new
residential construction (they don't say what it has to be just that
there is one)

On 21 Sep 2006 06:20:35 -0400, wrote:

Joe Fischer wrote:
Try your math on adding enough water to maintain
constant 50 percent relative humidity to change 10,000 cubic
feet of air every two hours (with zero people in the house).

No thanks. ASHRAE says houses need 15 cfm per occupant, so
zero people need zero cfm.
Nick

Furniture needs constant humidity, whole system
efficiency cannot be based on minimum regulations or
standards.

Efficiency experts are driving a lot of companies
out of business with bad advice, reduced inventories,
reduced hours, and eliminated services.

Joe Fischer

In article .com,
says...

wrote:
wrote:

On Tue, 19 Sep 2006 12:22:04 -0400, in misc.consumers.frugal-living Joe Fischer
wrote:

If doctors were to advise patients who get
head colds every winter to humidify when the
outdoor temperature is below 40 degrees F, the
number of head colds would be reduced by at
least half, and maybe as much as 80 percent less.


I find this very hard to believe.

You might find it so, but the experience of a lot of us who have moved
south gives it a lot of credence. In Vermont, I used to get at least
four colds a winter. In the humid south, catching a cold is a rare
event for me.

This would be easily explained if it was found that Vermonters have a
higher tendency to sneeze on each other, not wash hands often enough,
etc. Or maybe it's got nothing to do with Vermonters' habits or their
weather. I've lived in several climates and I've found that I'm more
likely to get sick when I've been around sick and/or contagious people.
Maybe it's them New Yawkers who come up to Vermont to ski that bring
their strange city germs.

Nah, I didn't have nearly as many colds when I lived in NY as I do
now in VT (just getting over a cold now, in fact). The reason
people get more colds in cold weather is that they're holed up
closer to each other. When it's warm they're outside more with
more separation.

I wonder what the rate of headcolds is among those of the "dry south"
compared to the "humid south"? This may shed light on the topic.

....but it's a dry cold! ;-)

--
Keith

On Thu, 21 Sep 2006 14:06:25 GMT, wmbjk wrote:

On Wed, 20 Sep 2006 12:58:04 -0400, Joe Fischer
wrote:
On Wed, wmbjk wrote:
sigh http://www.mayoclinic.com/health/com...056/DSECTION=3

I didn't say that germs are not involved, in fact,
I said germs are involved

"Involved" eh? Previously you wrote that "there may be colds that are
caught, but mine come from inflamed sinus irritated by dry air." So
here's your opportunity to make your opinion clear - do you believe
that you can catch a cold *without* exposure to a virus?

Without exposure to a person having a contagious
virus or whatever, you can believe it, I am a loner, having
been widowed and carrying the torch for 45 years.

Fifty percent relativity is just an easy to
maintain number, possibly in a clean house
any constant relative humidity that does not
irritate the sensitive nasal or airway passages
would do as well. (Constant RH!)

RH here this morning is 2%, but it can shift quickly and wildly during
monsoon season (just ending). According to your theory, we should be
afflicted by colds constantly. How do you explain the fact that we go
years between colds?

I spend a summer in Las Vegas, 1 percent and 115 degrees
was perfect for me.

Your advice reminds me of the self-titled country doctor who claimed a
miracle cure for the common cold. When a patient complained that he
still had the cold after a few days, the "doctor" told him the cure
takes at least a week.
Wayne

I am not a doctor and I did not claim a cure,
the suggested methods of prevention listed at the link
you provided are almost identical to what I do, except
my kids are fifty-ish and not in school.

Joe Fischer

Robert Gammon errs again:

Canada says all new houses there should be equipped with an air to air
heat exchanger that ventilate the house several times a day (I forget
the actual spec)

Do let us know when you find this alleged spec. Meanwhilst, you might
explain the new houses in Ontario with exhaust fans vs ERVs.

Even Washington state mandates a ventilation system in all new
residential construction (they don't say what it has to be just that
there is one)

Sounds like an exhaust fan would qualify there as well.

Nick

Joe Fischer errs again:

Furniture needs constant humidity...

Some does, and that's easy to do with minimal air leakage.

Nick

wrote:
Robert Gammon errs again:


Canada says all new houses there should be equipped with an air to air
heat exchanger that ventilate the house several times a day (I forget
the actual spec)


Do let us know when you find this alleged spec. Meanwhilst, you might
explain the new houses in Ontario with exhaust fans vs ERVs.


Even Washington state mandates a ventilation system in all new
residential construction (they don't say what it has to be just that
there is one)


Sounds like an exhaust fan would qualify there as well.

Nick


http://r2000.chba.ca/What_is_R2000/R2000_standard.php

YOU pointed the spec to us, NOW READ THIS PAGE

Note that this is not a MANDATORY construction method, it is a voluntary
program designed to influence both builders and consumers.



R-2000 homes will be blower door tested to ensure that the required
standard for air tightness is met.

Mechanical ventilation systems must be provided. Most R-2000 builders
use a Heat Recovery Ventilator



Note that not all R-2000 homes are REQUIRED to have HRVs, they point out
that builders who follow the spec to produce an R-2000 certified home
will often choose to include an HRV as the chosen ventilation method.

And Canada is far more than just Ontario, and Ontario is far more than
the southeastern region that lies just across the lake. Toronto
winters are very different than Chicoutimi, or Calgary, or even
locations in Ontario in the north and west regions. R-2000 addresses the
needs of the ENTIRE country.

On 21 Sep 2006 13:42:05 -0400, wrote:

Joe Fischer never errs again:
Furniture needs constant humidity...

Some does, and that's easy to do with minimal air leakage.
Nick

Make up your mind, is it leakage, or powered mandated
air exchange. Can the right amount of leakage qualify
as a measured amount of air exchange.
Is the heat in the air being exchanged all that much,
or is most of the heat in the solid objects in the house.
Do I really need another fan running to be called
an efficient house, does that make it more efficient or
greener, cleaner or meaner?

I would like to make a suggestion about all
government regulations other than safety and security.

Joe Fischer

Robert Gammon wrote:

Canada says all new houses there should be equipped with an air to air
heat exchanger...

Do "they" also say that all new houses "should" be painted white? :-)

http://r2000.chba.ca/What_is_R2000/R2000_standard.php

YOU pointed the spec to us, NOW READ THIS PAGE

No thanks.

Note that this is not a MANDATORY construction method, it is a voluntary
program designed to influence both builders and consumers.

Aha. That kind of "should," as in "All men should be named Dave."

And Canada is far more than just Ontario, and Ontario is far more than
the southeastern region that lies just across the lake. Toronto
winters are very different than Chicoutimi, or Calgary, or even
locations in Ontario in the north and west regions. R-2000 addresses the
needs of the ENTIRE country.

From the mountains, to the prairies,
to the oceans, white with foam...

Nick

Joe Fischer errs again:

Furniture needs constant humidity...

Some does, and that's easy to do with minimal air leakage.

... is it leakage, or powered mandated air exchange.

You might enjoy figuring that out :-)

Can the right amount of leakage qualify as a measured amount of air exchange.

Not on a mild day.

Is the heat in the air being exchanged all that much,

Not at all, with an exhaust fan.

Do I really need another fan running to be called an efficient
house, does that make it more efficient or greener, cleaner or meaner?

Only your hairdresser knows for sure.

Nick

wrote:
Robert Gammon wrote:


Canada says all new houses there should be equipped with an air to air
heat exchanger...


Do "they" also say that all new houses "should" be painted white? :-)

http://r2000.chba.ca/What_is_R2000/R2000_standard.php


YOU pointed the spec to us, NOW READ THIS PAGE


No thanks.


Note that this is not a MANDATORY construction method, it is a voluntary
program designed to influence both builders and consumers.


Aha. That kind of "should," as in "All men should be named Dave."


And Canada is far more than just Ontario, and Ontario is far more than
the southeastern region that lies just across the lake. Toronto
winters are very different than Chicoutimi, or Calgary, or even
locations in Ontario in the north and west regions. R-2000 addresses the
needs of the ENTIRE country.


From the mountains, to the prairies,
to the oceans, white with foam...

Nick


Now it was Nick who pointed out that IDEA 2000homes in Canada leak at
2.5CFM vs 200CFM for good US houses, and now he won't even read the
pages from whence these figures were quoted!!!!!!


Aha should back at you, as if my house can be adequately conditioned
(Heated and cooled) by burying 500 feet of 6 inch diameter pipe 6 feet
below the surface and blow 300 CFM thru the pipe. In SOME parts of the
US that will work in combination with solar heat management, great
insulation.... Temperature to cool climates yes, however I do not live
in a temperate climate. AC runs a few hours EVERY SINGLE MONTH OF THE YEAR.



It just won't work. One size does not fit all!!!

"Joe Fischer" wrote in message
news
On Tue, 19 Sep 2006 19:49:05 GMT, "daestrom"
wrote:

As nick pointed out, the cheapest way to remove humidity is with a
dehumidifier. The heat removed from the moisture is dumped back into the
room. Running the A/C dumps heat outside and has to be replaced by
running
the heater. VERY BAD idea.

Modern A/Cs do not drip water because they port
the condensate out to the warm side and either spray it
on warm parts or immerse the motor housing and tubing
in it.

Who said anything about water dripping outside? I was talking about the
amount of *heat* that is moved from inside to outside in the process and
having to replace the *heat*.

Note that the only day in the entire year where
I found it necessary was not a hot day, it was a quite
cool day, cool enough that heat could be used.

Of course if there is a place that has that much
moisture much of the time, they need dehumidifiers.

A house with a wooden floor and basement
or crawl space should not normally be damp enough
to need dehumidification, it is slab homes and
basements that need it.

Before the condensate from an A/C was
evaporated outside, an average size A/C would
sometimes condense more water per hour than
three or four dehumidifiers.
And I assume the modern ones do - also.


Yep. But a dehumidifier doesn't *cool* the house down (you mentioned, "it
was a quite cool day"). A/C will remove a lot of moisture, but if the
temperature in the house drops and you have to turn on the heat to
compensate, then you're really paying a lot ot remove that moisture.
Dehumidifiers will remove the moisture without removing heat from the house,
so you don't need to turn on the heater as well.

Yeah, once or twice a year isn't much of a problem (maybe cost you $2). But
if it were a common occurance (high humidity without high temperatures),
then a dehumidifier would be the way to go.

daestrom

wrote in message
...
Joseph Meehan wrote:

Any house that needs winter humidification needs air sealing.

Not always...

I'd say always. Andersen says an average family of 4 puts about 2 gallons
per day of water (16.7 pounds) into house air. In an absolutely airtight
house, the RH would rise to 100% near windows with wintertime
condensation.

ASHRAE says houses need 15 cfm of fresh air per full-time occupant, so
4 half-time occupants need 30 cfm at 0.075 lb/ft^3, ie 30x60mx24hx0.075
= 3240 lb/day of fresh air. January outdoor air in Phila has an average
humidity ratio wo = 0.0032 pounds of water per pound of dry air. If
minimal
ventilation with no condensation removes 3240(wi-wo) = 16.7 lb/day of
water
from the house, wi = 0.00834, and 70 F air at 100% RH has w = 0.0158, so
the house RH would be about 100wi/w = 53% with minimal ventilation, or
more,
with a small efficient air-air heat exchanger with outgoing condensation.


What do the numbers look like with an average outside dewpoint of 0F ??
While the daily 'highs' here can sometimes reach 30F, the overnight low and
dewpoint of outside air is usually much lower for Jan/Feb. My psychrometric
charts don't go down that far so I can't do the calc.

Seems like 'always' is a pretty risky statement considering some parts of
the country. Pellston MI is often one of the coldest places in CONUS, or
International Falls MN.

How much air exchange happens when the door is opened eight times a day
(four people leaving for work/school and returning). Just wondered if you
have some data on that?

daestrom

"Joe Fischer" wrote in message
...
On 21 Sep 2006 06:20:35 -0400, wrote:

Joe Fischer wrote:
Try your math on adding enough water to maintain
constant 50 percent relative humidity to change 10,000 cubic
feet of air every two hours (with zero people in the house).

No thanks. ASHRAE says houses need 15 cfm per occupant, so
zero people need zero cfm.
Nick

Furniture needs constant humidity, whole system
efficiency cannot be based on minimum regulations or
standards.

Efficiency experts are driving a lot of companies
out of business with bad advice, reduced inventories,
reduced hours, and eliminated services.


You really are 'reading' Nick the wrong way.

Yes, warming outside air as it enters a house lowers its RH (doesn't change
its dewpoint or specific humidity though). Yes, most people are more
comfortable with RH around 50%, and many household items such as wood
furniture are less likely to shrink/crack if the humidity is maintained.

Nick is *only* saying that you don't need to add a lot of moisture to the
air *if* you don't have a lot of air exchange. If air exchange is kept down
to a minimum, then the amount of moisture you have to add is also a minimum.
Experts/standards tell us that you *don't* need a whole-house air change
every 2 or 3 hours. *That* level of air exchange does require you to add a
lot of moisture. And that takes a lot of energy.

Reducing the air exchange rate to something a lot closer to the 'standards'
level will greatly reduce the amount of moisture that needs to be constantly
added to a house. Nick *has* said that with the minimum air exchange, the
moisture given off by people and activities will accumulate enough to raise
the humidity into the 'comfort zone'. But I think that would only be true
in mild winter climates such as his (Philidelphia).

Nick also maintains that the old wive's tail that humidifying your house
saves energy is bunk. It may feel more comfortable, but it takes more
energy to maintain that humidity level than it does to just maintain the air
temperature. Lowering the exchange rate will save energy in two ways, a) it
lowers the amount of heat lost with the outgoing air, and b) it lowers the
amount of energy needed to maintain comfortable humidity levels.

daestrom

"Joe Fischer" wrote in message
...
On Tue, 19 Sep 2006 20:34:06 GMT, "daestrom"
wrote:

snip

It sounds like you and Nick did not appreciate
or understand what I posted about the absorption and
emission of water vapor from carpets and fabrics.


No, I don't think so. I was pointing out that dewpoint is a much better
measure of the amount of moisture in the air than RH. After all, in the
winter time around here when it's 20F, the weather report often says
humidity is above 75%. Of course that's the RH at the prevailing
temperature (20F) and not very meaningful. You have to do a lot of
calculations or use a chart to figure out what that would be if heated up to
70F. But compare the dewpoint (about 15F) with a desired dewpoint of 45F
and it's easy to tell that the air is really 'dry'.

And there is a huge difference in noses, some (me)
actually have capillary bleeding if the air gets too dry,
sometimes a cold follows, sometimes not.


My son has that problem. If I don't humidify the house, he'll wake up with
blood stains on his pillow each morning.

I can feel the drying of my sinus in a 20 mile
trip in the car with A/C set to 70 degrees on a hot day.


Airplane trips are another nasty one. The air at 35,000 feet has a very low
dewpoint.

The problem is, studies may not show anything
definite about the nose, and the "disease" is not considered
serious enough to warrant serious study.
But I am surprised there is not definitive data
on the drying of expensive wood items, especially
antiques and artifacts.


I'm sure there is. Museums often put precious relics in climate controlled
cases. Gettysburg has a lot of Civil War memorabilia that is preserved this
way. Uniforms and leather items are subject to this issue as well.

So any company that sells humidifiers should
keep on selling, and advertise what they do for wood
and fabrics, if not for people or noses.
I don't have any fine wood items, but I have
a nose that has a lot of influence on my H, V, and A/C.


Well, I agree with Nick that humidification costs you energy, it doesn't
save energy. But that's not to say that you shouldn't do something to
control the humidity levels. Nick likes to play with numbers and posit some
'we could' or 'it might'. Gets people thinking. If we reduce the
air-exchange rate, we don't have to work as hard to maintain a nice humidity
level. Nick is fond of quoting ASHRAE (the manuals cost a lot, may as well
get his money's worth). I'm not so sure that as little as 15 cfm is enough
to maintain "indoor pollution" levels, but I have to agree that most US
homes are much too 'leaky'. An air-exchange every couple of hours seems
like way too much.

But then, I lived on a submarine for years, so I may be a little more
sensitive to air contamination issues than some folks. Ventilation is one
way to reduce indoor air pollution levels, but removing the source of the
contaminants is another. No contaminants, don't need much ventilation.
Little ventilation, less moisture needs to be constantly added to maintain
'comfort' levels.

daestrom

"wmbjk" wrote in message
...
On Tue, 19 Sep 2006 18:16:07 -0400, Joe Fischer
wrote:

On Tue, 19 Sep 2006 19:43:59 GMT, wmbjk wrote:

close contact with others who
have colds.

Bingo. Forget the other stuff.

Sorry, Doctor, there may be colds that are "caught",
but mine come from inflamed sinus irritated by dry air.

No, that's just what you *believe*.

You need to do some reading before spreading old-wives' tales.
http://en.wikipedia.org/wiki/Common_cold

Glad you have such faith in articles written
by just anybody who wants to write or modify them.

sigh http://www.mayoclinic.com/health/com...056/DSECTION=3
Although I predict that you won't believe the Mayo Clinic either. The
fact is that the cause of the common cold has been known for a long
time. Unfortunately, a lot of people insist on spreading nonsense
instead.


Well of course colds are caused by virsuses (virii??). But if someone's
natural defenses are weakened, doesn't that make them more susceptable to
infection? If your sinuses are cracked and bleeding, isn't it more likely
you will 'catch' one of those viruses floating around in a closed space?

The nasal passages are our first line of defense against such airborne
infection. If some folks sinuses are particularly sensitive to drying, it
seems quite logical that airborne infections have a better chance of taking
hold in the body and causing illness.

From your article by the Mayo Clinic, on 'risk factors' :
"Some researchers theorize that cold constricts blood vessels in the nose,
slowing the white cells that fight infection and disrupting the first-line
defense against germs. "

This supports the belief that your nose is the 'first-line defense against
germs'. So doing something to keep from degrading its ability seems only
natural.

daestrom

daestrom wrote:

wrote in message

... Andersen says an average family of 4 puts about 2 gallons per day
of water (16.7 pounds) into house air. In an absolutely airtight house,
the RH would rise to 100% near windows with wintertime condensation.

ASHRAE says houses need 15 cfm of fresh air per full-time occupant, so
4 half-time occupants need 30 cfm at 0.075 lb/ft^3, ie 30x60mx24hx0.075
= 3240 lb/day of fresh air. January outdoor air in Phila has an average
humidity ratio wo = 0.0032 pounds of water per pound of dry air. If
minimal ventilation with no condensation removes 3240(wi-wo) = 16.7 lb/day
of water from the house, wi = 0.00834, and 70 F air at 100% RH has
w = 0.0158, so the house RH would be about 100wi/w = 53% with minimal
ventilation, or more, with a small efficient air-air heat exchanger
with outgoing condensation.

What do the numbers look like with an average outside dewpoint of 0F ??

Table 2 in the ASHRAE HOF says the humidity ratio wo = 0.0007875 at 0 F,
which would make wi = 0.00593 with a 38% RH above, or more, with some
outgoing condensation.

While the daily 'highs' here can sometimes reach 30F, the overnight low and
dewpoint of outside air is usually much lower for Jan/Feb.

Since many house materials (cloth, wood, paper, concrete) can store moisture,
it seems like a good idea to ventilate houses during the day in wintertime,
when outdoor temps are warmer. An exhaust fan might have a timer, as well
as a humidistat.

Seems like 'always' is a pretty risky statement considering some parts of
the country. Pellston MI is often one of the coldest places in CONUS, or
International Falls MN.

International Falls has wo = 0.0009 with an average 1.0 F outdoor temp in
January. Brrr.

How much air exchange happens when the door is opened eight times a day
(four people leaving for work/school and returning). Just wondered if you
have some data on that?

I have no data, but if the door's open for 3 seconds each time, that's 24
seconds total, ie 0.4 minutes per day. With 16.6x16ft^2sqrt(70F-0F)4')
= 4444 cfm when the door is open, we might move 0.4x4444 = 1778 ft^3/day
of fresh air into the house, ie 1778/24/60 = 1.2 cfm, averaged over 24h.

Airlock entrances just for the purpose of saving heat energy (vs mudrooms
that keep a house cleaner, etc.), don't seem worth the cost except for
department stores or very large busy families.

Nick

On Thu, 21 Sep 2006 20:12:55 GMT, "daestrom"
wrote:

Dehumidifiers will remove the moisture without removing heat from the house,
so you don't need to turn on the heater as well.

Yeah, once or twice a year isn't much of a problem (maybe cost you $2). But
if it were a common occurance (high humidity without high temperatures),
then a dehumidifier would be the way to go.
daestrom

Which is why I did it, today it was cool enough that
the RH in my room is less than 65, the day I mentioned
it was 90, which is extremely high for indoors in a raised
wooden floor house.

Another problem is that with age and circulation
resulting from age, breathing can be a more important
issue than the 4 hours of 1 KW at $.06.
And I didn't need an $80,000 a year efficiency
expert to figure that out for me. :-)

Joe Fischer

On Thu, 21 Sep 2006 20:48:19 GMT, "daestrom"
wrote:

No, I don't think so. I was pointing out that dewpoint is a much better
measure of the amount of moisture in the air than RH.

Aren't they related?

After all, in the
winter time around here when it's 20F, the weather report often says
humidity is above 75%. Of course that's the RH at the prevailing
temperature (20F) and not very meaningful. You have to do a lot of
calculations or use a chart to figure out what that would be if heated up to
70F. But compare the dewpoint (about 15F) with a desired dewpoint of 45F
and it's easy to tell that the air is really 'dry'.

I think the weather man here shows dew points when
there is storm danger.

And there is a huge difference in noses, some (me)
actually have capillary bleeding if the air gets too dry,
sometimes a cold follows, sometimes not.

My son has that problem. If I don't humidify the house, he'll wake up with
blood stains on his pillow each morning.

I haven't had it for a long time, because I hate
the colds so much. I have had jobs where I was in
close contact with a lot of people, and worked outside
in all kinds of weather, but only got a cold when the
humidity wasn't kept high while sleeping.

on the drying of expensive wood items, especially
antiques and artifacts.

I'm sure there is. Museums often put precious relics in climate controlled
cases. Gettysburg has a lot of Civil War memorabilia that is preserved this
way. Uniforms and leather items are subject to this issue as well.

I think even food needs to be kept in a controlled
environment to stay fresh and edible longer.

So any company that sells humidifiers should
keep on selling, and advertise what they do for wood
and fabrics, if not for people or noses.
I don't have any fine wood items, but I have
a nose that has a lot of influence on my H, V, and A/C.

Well, I agree with Nick that humidification costs you energy, it doesn't
save energy. But that's not to say that you shouldn't do something to
control the humidity levels. Nick likes to play with numbers and posit some
'we could' or 'it might'. Gets people thinking. If we reduce the
air-exchange rate, we don't have to work as hard to maintain a nice humidity
level. Nick is fond of quoting ASHRAE (the manuals cost a lot, may as well
get his money's worth). I'm not so sure that as little as 15 cfm is enough
to maintain "indoor pollution" levels, but I have to agree that most US
homes are much too 'leaky'. An air-exchange every couple of hours seems
like way too much.

Most homes have plaster or drywall walls and ceilings,
so there isn't much that can be done other than doors and
windows. The modern furnace has eliminated the loss
to vented flame, so it gets down pretty much to windows.

Is Nick a window salesman? :-) :-)

But then, I lived on a submarine for years, so I may be a little more
sensitive to air contamination issues than some folks. Ventilation is one
way to reduce indoor air pollution levels, but removing the source of the
contaminants is another. No contaminants, don't need much ventilation.
Little ventilation, less moisture needs to be constantly added to maintain
'comfort' levels.
daestrom

I had the impression that I was reducing ventilation
when I began using baseboard electric in place of vented
gas stoves. Five years ago I turned off the supply valve
to my 1960 Magic Chef range so I would not have to run
two pilot lights for the top burners and one for the oven.

Two years ago I replaced the gas water heater with
an electric, and assumed the new one would be insulated
well enough to not use much electric, I have my laundry
done out, and only use hot water for bathing (not often
enough).

I have done a lot of sealing on the house, not all
to reduce ventilation. I sealed one room on the inside
with clear silicone so I would not have to repaint at the
time, but I sealed that to reduce pollution caused by
my Aunt having casual labor blow insulation in the
attic, and this house (any house) should have an expert
seal the attic and prepare it properly before installing.
This house was especially bad because it wasn't
plastered, it had one inch oak run vertically for the
interior walls, and that leaves cracks.

I also sealed the two back rooms that were replaced
in 1937 after the flood took off the two original added-on
rooms, but not to save energy, I did it to keep out the
rotten Box Elder bugs that are totally harmless and
don't get into food, and only want a warm place to
winter (but they look too much like young cockroaches).
5000 in the kitchen was too much for me when
they tried to find their way outside in the spring, and
the neighbor won't let me cut down the Manitoba
Maple (Box Elder).

I have pretty much abandoned the outside and
back yard, the environment has become hostile with
snakes, stray cats by the dozen, raccoons, opossum,
groundhogs, moles, squirrels, huge spiders, carpenter
bees, wasps, hornets, mosquitos, sand fleas, and fleas
and ticks spread by the cats and the rotten Box Elders.

So a little ventilation is not so bad, as long
as it is through the screen door. I don't have
a powered ventilator with humidistat, but I
have a through-the-wall fan, and being every
doorway in the house has a door (no arches),
I can either circulate air around four rooms
to achieve even cooling or heat and to avoid
stale air in a room, or I can open the back
door and front door and close the kitchen door,
and the fan will draw air in the front door screen
and out the back porch screen.

A small fan uses a lot less power than an
A/C, and if the house is hot on cool nights, the
fan is the thing to use, less noise and fresh air.

Note that Nick inserts smileys :-), he
does that because he knows the decimal
places are meaningless after the calculation
is over. :-)

I have no idea how to proceed if I were
to try to approach the dry air at night in winter
problem by trying to control ventilation.
I can't totally seal the outside doors, that
is the only place air can enter if I am forced
to run the Cozy stoves.
I see unvented stoves and heaters for sale,
but I don't want one. All I can do is use as
little electric resistance as possible, and have
full use of the whole house on milder days.
And continue to run the steam humidifier/
vaporizer while I am sleeping only, when the
outside temp is below 40.

Joe Fischer

Joe Fischer wrote:

No, I don't think so. I was pointing out that dewpoint is a much better
measure of the amount of moisture in the air than RH.

Aren't they related?

Sure. Tdp (R) = T(R)/(1+T(R)ln(RH%/100)/9621.)

I think the weather man here shows dew points when
there is storm danger.

Pilots suspect fog if the dew point is within a few degrees of the air temp.

Is Nick a window salesman? :-) :-)

No...

I have no idea how to proceed if I were to try to approach
the dry air at night in winter problem by trying to control ventilation.

Airseal your house.

Nick

On Thu, 21 Sep 2006 20:57:18 GMT, "daestrom"
wrote:


"wmbjk" wrote in message
.. .
On Tue, 19 Sep 2006 18:16:07 -0400, Joe Fischer
wrote:

On Tue, 19 Sep 2006 19:43:59 GMT, wmbjk wrote:

close contact with others who
have colds.

Bingo. Forget the other stuff.

Sorry, Doctor, there may be colds that are "caught",
but mine come from inflamed sinus irritated by dry air.

No, that's just what you *believe*.

You need to do some reading before spreading old-wives' tales.
http://en.wikipedia.org/wiki/Common_cold

Glad you have such faith in articles written
by just anybody who wants to write or modify them.

sigh http://www.mayoclinic.com/health/com...056/DSECTION=3
Although I predict that you won't believe the Mayo Clinic either. The
fact is that the cause of the common cold has been known for a long
time. Unfortunately, a lot of people insist on spreading nonsense
instead.


Well of course colds are caused by virsuses (virii??). But if someone's
natural defenses are weakened, doesn't that make them more susceptable to
infection? If your sinuses are cracked and bleeding, isn't it more likely
you will 'catch' one of those viruses floating around in a closed space?

The nasal passages are our first line of defense against such airborne
infection. If some folks sinuses are particularly sensitive to drying, it
seems quite logical that airborne infections have a better chance of taking
hold in the body and causing illness.

From your article by the Mayo Clinic, on 'risk factors' :
"Some researchers theorize that cold constricts blood vessels in the nose,
slowing the white cells that fight infection and disrupting the first-line
defense against germs. "

This supports the belief that your nose is the 'first-line defense against
germs'. So doing something to keep from degrading its ability seems only
natural.

Sure, but he's claiming that he can get a cold by (effectively)
weakened defenses alone, as in, without a virus being present to
defend against. That's pretty much the same as the old-wives tale
about wet hair causing colds.

Wayne

On Thu, 21 Sep 2006 12:34:15 -0400, Joe Fischer
wrote:

On Thu, 21 Sep 2006 14:06:25 GMT, wmbjk wrote:

On Wed, 20 Sep 2006 12:58:04 -0400, Joe Fischer
wrote:
On Wed, wmbjk wrote:
sigh http://www.mayoclinic.com/health/com...056/DSECTION=3

I didn't say that germs are not involved, in fact,
I said germs are involved

"Involved" eh? Previously you wrote that "there may be colds that are
caught, but mine come from inflamed sinus irritated by dry air." So
here's your opportunity to make your opinion clear - do you believe
that you can catch a cold *without* exposure to a virus?

Without exposure to a person having a contagious
virus or whatever, you can believe it,

No, I don't believe it, and neither would any logical person. Of
course if you can deny the well-established cause of the common cold,
then I suppose you won't have any trouble denying that you're
illogical as well.

I am a loner, having
been widowed and carrying the torch for 45 years.

Being a widower hardly prevents human contact. All you need to do is
put your hands on a grocery buggy for example and you can make contact
with a virus.

Wayne

wrote:

Robert Gammon errs again:

Canada says all new houses there should be equipped with an air to air
heat exchanger that ventilate the house several times a day (I forget
the actual spec)

Do let us know when you find this alleged spec. Meanwhilst, you might
explain the new houses in Ontario with exhaust fans vs ERVs.

Building code requires a "balanced ventilation system". What exactly that
means is highly dependent on the building inspector you get. _Many_
inspectors take that to mean an HRV.

Sounds like an exhaust fan would qualify there as well.

My friend who builds passive-solar homes has argued this for years. Given
that he's a qualified engineer AND architect, he knows what he's talking
about, but he still has trouble with some inspectors.
--
derek

On 21 Sep wrote:

Airseal your house.
Nick

You have a one-track mind :-)

When you get to be an injun ear, work on the
fine points, not the generalities. :-)

If I seal my house ___AIRTIGHT___, leave
on vacation when it is 70 F outside with everything
turned off, and return after it has been 20 degrees
outside for a week, and the indoor temp is 40 degrees F,
and RH is 50 percent, how much water would I need to
add if I raise the air temp to 70 F and want 50 percent RH.

Joe Fischer

On Fri, wmbjk wrote:

No, I don't believe it, and neither would any logical person. Of
course if you can deny the well-established cause of the common cold,
then I suppose you won't have any trouble denying that you're
illogical as well.

Maybe you can tell us how many different bacterial
and viral diseases go by the name "common cold".

If you premise were correct, if nobody got a cold
all summer, then there would be no cold germs around.

I see you claim as requiring that the total reservoir
of cold germs are in the nasal passages and airways of
humans.

I have to think the germs are more widespread than
that, and exist with or without humans.

The link you provided seems to say that colds are
the result of the germs overwhelming the immune system,
and that it is possible for a person to be exposed and still
ward off the bad cold.

Are you claiming that a person gets a cold just
because they come in contact with somebody with a cold,
and never get a cold otherwise?

Joe Fischer

Joe Fischer wrote:

If... the indoor temp is 40 degrees F, and RH is 50 percent,
how much water would I need to add if I raise the air temp
to 70 F and want 50 percent RH.

Good question. And your answer?

And your point?

Nick

Joe Fischer wrote:
On Thu, 21 Sep 2006 20:48:19 GMT, "daestrom"
wrote:


No, I don't think so. I was pointing out that dewpoint is a much better
measure of the amount of moisture in the air than RH.


Aren't they related?


After all, in the
winter time around here when it's 20F, the weather report often says
humidity is above 75%. Of course that's the RH at the prevailing
temperature (20F) and not very meaningful. You have to do a lot of
calculations or use a chart to figure out what that would be if heated up to
70F. But compare the dewpoint (about 15F) with a desired dewpoint of 45F
and it's easy to tell that the air is really 'dry'.


I think the weather man here shows dew points when
there is storm danger.



Actually, my local weather posts dew point 24x7

Right now (4:00am ) in Houston TX, using data from a TV station with
studios about 3 miles away,

Temp is 81F
DewPoint is 75F

Pretty high RH, eh??

"Joe Fischer" wrote in message
...
On Thu, 21 Sep 2006 20:48:19 GMT, "daestrom"
wrote:

No, I don't think so. I was pointing out that dewpoint is a much better
measure of the amount of moisture in the air than RH.

Aren't they related?


Yes, but you have to 'adjust' the RH from the temperature it is measured at,
to the temperature that you want. Dewpoint doesn't need adjusting. A
dewpoint above about 55F is 'high humidity' and a dewpoint below 30F is 'low
humidity'. Period, all the time, every way you look at it.


snip
So any company that sells humidifiers should
keep on selling, and advertise what they do for wood
and fabrics, if not for people or noses.
I don't have any fine wood items, but I have
a nose that has a lot of influence on my H, V, and A/C.

Well, I agree with Nick that humidification costs you energy, it doesn't
save energy. But that's not to say that you shouldn't do something to
control the humidity levels. Nick likes to play with numbers and posit
some
'we could' or 'it might'. Gets people thinking. If we reduce the
air-exchange rate, we don't have to work as hard to maintain a nice
humidity
level. Nick is fond of quoting ASHRAE (the manuals cost a lot, may as
well
get his money's worth). I'm not so sure that as little as 15 cfm is
enough
to maintain "indoor pollution" levels, but I have to agree that most US
homes are much too 'leaky'. An air-exchange every couple of hours seems
like way too much.

Most homes have plaster or drywall walls and ceilings,
so there isn't much that can be done other than doors and
windows. The modern furnace has eliminated the loss
to vented flame, so it gets down pretty much to windows.

Is Nick a window salesman? :-) :-)


No, but I can see how you might think that :-)

But then, I lived on a submarine for years, so I may be a little more
sensitive to air contamination issues than some folks. Ventilation is one
way to reduce indoor air pollution levels, but removing the source of the
contaminants is another. No contaminants, don't need much ventilation.
Little ventilation, less moisture needs to be constantly added to maintain
'comfort' levels.
daestrom

I had the impression that I was reducing ventilation
when I began using baseboard electric in place of vented
gas stoves. Five years ago I turned off the supply valve
to my 1960 Magic Chef range so I would not have to run
two pilot lights for the top burners and one for the oven.

Two years ago I replaced the gas water heater with
an electric, and assumed the new one would be insulated
well enough to not use much electric, I have my laundry
done out, and only use hot water for bathing (not often
enough).


Yes, those things do reduce the ventilation. But if you have 'leaky' walls
and window casings, a mildly windy day can completely overwhelm those
savings. A lot of modern stoves/ovens use electronic ignition to avoid
pilots. When you replaced the water heater, did you seal off the flue?

Funny thing about pilot lights though, when the natural gas burns it forms
CO2 and H2O. So a small pilot actually puts some moisture into the air.
Now, whether that actually raises humidity, or lowers it would depend on the
water vapor formed by the burning gas, versus the increase in air-exchange
with dryer outside air (and just how dry the outside air is).

I have done a lot of sealing on the house, not all
to reduce ventilation. I sealed one room on the inside
with clear silicone so I would not have to repaint at the
time, but I sealed that to reduce pollution caused by
my Aunt having casual labor blow insulation in the
attic, and this house (any house) should have an expert
seal the attic and prepare it properly before installing.
This house was especially bad because it wasn't
plastered, it had one inch oak run vertically for the
interior walls, and that leaves cracks.


Hmmmm.... cracks bad.... nice oak wood walls, good (esthetically pleasing).

snip

So a little ventilation is not so bad, as long
as it is through the screen door. I don't have
a powered ventilator with humidistat, but I
have a through-the-wall fan, and being every
doorway in the house has a door (no arches),
I can either circulate air around four rooms
to achieve even cooling or heat and to avoid
stale air in a room, or I can open the back
door and front door and close the kitchen door,
and the fan will draw air in the front door screen
and out the back porch screen.

A small fan uses a lot less power than an
A/C, and if the house is hot on cool nights, the
fan is the thing to use, less noise and fresh air.


As with most things in life, the key is finding the right balance. And
what's right for you....

Note that Nick inserts smileys :-), he
does that because he knows the decimal
places are meaningless after the calculation
is over. :-)

I have no idea how to proceed if I were
to try to approach the dry air at night in winter
problem by trying to control ventilation.
I can't totally seal the outside doors, that
is the only place air can enter if I am forced
to run the Cozy stoves.

Trade offs. If you could seal the doors better, and maybe a few other
obvious air leaks, you might not need the 'Cozy stoves' most days. Depends
on how cold it gets, how many sweaters you were, and how much other
insulation the house has. But once you have to start them, you need
ventilation to avoid CO poisoning.

I see unvented stoves and heaters for sale,
but I don't want one. All I can do is use as
little electric resistance as possible, and have
full use of the whole house on milder days.
And continue to run the steam humidifier/
vaporizer while I am sleeping only, when the
outside temp is below 40.


Good luck.

daestrom

On Thu, 21 Sep 2006 21:20:06 -0400, Joe Fischer
wrote:

On Fri, wmbjk wrote:

No, I don't believe it, and neither would any logical person. Of
course if you can deny the well-established cause of the common cold,
then I suppose you won't have any trouble denying that you're
illogical as well.

Maybe you can tell us how many different bacterial
and viral diseases go by the name "common cold".

Why would I do that? Any web search you do will show that there are
hundreds, but that none are called "dry nose" or whatever.

If you premise were correct, if nobody got a cold
all summer, then there would be no cold germs around.

No, that doesn't follow at all. Being exposed to a virus doesn't mean
you'll catch a cold. Yet it's both easy to come into contact with a
virus, and difficult for the virus to take hold. You can dramatically
increase the odds of avoiding affliction by using common sense, such
as hand washing before putting your hands near your face after
visiting a crowded store full of kiddies for example.

I see you claim as requiring that the total reservoir
of cold germs are in the nasal passages and airways of
humans.

I'm getting that you see the facts however you like.

I have to think the germs are more widespread than
that, and exist with or without humans.

How would that help rationalize your belief that colds aren't always
caused by "germs"?

The link you provided seems to say that colds are
the result of the germs overwhelming the immune system,
and that it is possible for a person to be exposed and still
ward off the bad cold.

Of course. And IIRC, if one has already been exposed to a particular
virus, then one is unlikely to develop a cold from further exposure to
the same virus.


Are you claiming that a person gets a cold just
because they come in contact with somebody with a cold,
and never get a cold otherwise?

I'm not claiming anything, just telling you the facts. You can't catch
a cold without being exposed to a virus.

Wayne

wmbjk wrote:
On Thu, 21 Sep 2006 21:20:06 -0400, Joe Fischer
wrote:

On Fri, wmbjk wrote:

No, I don't believe it, and neither would any logical person. Of
course if you can deny the well-established cause of the common
cold, then I suppose you won't have any trouble denying that you're
illogical as well.

Maybe you can tell us how many different bacterial
and viral diseases go by the name "common cold".

Why would I do that? Any web search you do will show that there are
hundreds, but that none are called "dry nose" or whatever.

If you premise were correct, if nobody got a cold
all summer, then there would be no cold germs around.

No, that doesn't follow at all. Being exposed to a virus doesn't mean
you'll catch a cold. Yet it's both easy to come into contact with a
virus, and difficult for the virus to take hold. You can dramatically
increase the odds of avoiding affliction by using common sense, such
as hand washing before putting your hands near your face after
visiting a crowded store full of kiddies for example.

I see you claim as requiring that the total reservoir
of cold germs are in the nasal passages and airways of
humans.

I'm getting that you see the facts however you like.

I have to think the germs are more widespread than
that, and exist with or without humans.

How would that help rationalize your belief that colds aren't always
caused by "germs"?

The link you provided seems to say that colds are
the result of the germs overwhelming the immune system,
and that it is possible for a person to be exposed and still
ward off the bad cold.

Of course. And IIRC, if one has already been exposed to a particular
virus, then one is unlikely to develop a cold from further exposure to
the same virus.


Are you claiming that a person gets a cold just
because they come in contact with somebody with a cold,
and never get a cold otherwise?

I'm not claiming anything, just telling you the facts.
You can't catch a cold without being exposed to a virus.

And the evidence for that last is that those who 'live' in isolated
environments like lighthouses etc dont ever get colds regardless
of what the room humidity is, because there are no viruses around.

Its less clear scientifically whether the room humidity has any effect
on the infection rate when there are viruses around. Its unlikely in
my opinion and the most likely reason why so many older people
dont get colds anymore is likely just because they are immune to
the vast bulk of cold seen, just because they have had so much
more exposure to them than say kids ever get, just due to the
vastly higher number of years of exposure to them and the fact that
its been carefully established that there are so many strains extant.