In an attempt to reduce my heating bills, and at the suggestion of a friend
of
mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased. This
results in my windows in that part of the house fogging up when the dryer
has been
running for an extended period but it does seem to dissipate fairly quickly.
I wondered if anyone else had tried this and whether or not it had worked
out
in the long run. I heat with a natural gas forced air furnace. Thanks.

"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket
of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased.
This
results in my windows in that part of the house fogging up when the dryer
has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had worked
out
in the long run. I heat with a natural gas forced air furnace. Thanks.




Stupid at best.

Dangerous and deadly at worst.

Follow your dryer's installation instructions. Never vent a dryer indoors.

First problem: using resistive electric heating for drying. Gas
enormously preferable. Much more so: fresh air & sunshine (even below
freezing) then a while near the woodstove.

Your idea of a lint trap sound totally useless. You will be spreading
all manner of that crap in your house.

With all the moisture you trap in the house, and without monitoring the
RH in any way, you should expect to find parts of the house getting
punky before long. You'd be amazed where.

J

Jackie wrote:

In an attempt to reduce my heating bills, and at the suggestion of a friend
of mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased. This
results in my windows in that part of the house fogging up when the dryer
has been running for an extended period...

You might avoid this problem by venting the dryer into a plastic trash can
full of 2-liter water bottles, with a drain...

Nick

Oscar_Lives wrote:
"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose
from blowing outside the house to inside and positioned it over a
small bucket of
water which acts as a lent trap. Now all that "paid for" warm air
stays inside but naturally the humidity level inside the house has
increased. This
results in my windows in that part of the house fogging up when the
dryer has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had
worked out
in the long run. I heat with a natural gas forced air furnace.
Thanks.



Stupid at best.

Dangerous and deadly at worst.

Follow your dryer's installation instructions. Never vent a dryer
indoors.

Note the OP wrote " I very recently have redirected my electric dryer
vent" Notice that is electric dryer. I would not say it was stupid or
generally dangerous. Had it been a gas dryer then it would have been
stupidly dangerous.

That said I would not do it myself, at least not likely. In fact if I
wanted to save on energy expense I would replace that electric dryer with a
gas dryer. In any case I don't like the idea. Even with one of the "lint
traps" very find lint still is going to find its way into your home. That
excessive moisture (condensation on the windows) can contribute to mold and
structural damage. Finally that lint filter can cause increased back
pressure and less efficiency for the dryer. I just don't think the savings
are worth the risks.


--
Joseph Meehan

Dia duit

"Joseph Meehan" wrote in message
news
Oscar_Lives wrote:
"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose
from blowing outside the house to inside and positioned it over a
small bucket of
water which acts as a lent trap. Now all that "paid for" warm air
stays inside but naturally the humidity level inside the house has
increased. This
results in my windows in that part of the house fogging up when the
dryer has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had
worked out
in the long run. I heat with a natural gas forced air furnace.
Thanks.



Stupid at best.

Dangerous and deadly at worst.

Follow your dryer's installation instructions. Never vent a dryer
indoors.

Note the OP wrote " I very recently have redirected my electric dryer
vent" Notice that is electric dryer. I would not say it was stupid or
generally dangerous. Had it been a gas dryer then it would have been
stupidly dangerous.

That said I would not do it myself, at least not likely. In fact if I
wanted to save on energy expense I would replace that electric dryer with
a gas dryer. In any case I don't like the idea. Even with one of the
"lint traps" very find lint still is going to find its way into your home.
That excessive moisture (condensation on the windows) can contribute to
mold and structural damage. Finally that lint filter can cause increased
back pressure and less efficiency for the dryer. I just don't think the
savings are worth the risks.


--
Joseph Meehan


I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

Oscar_Lives wrote:

I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

Wrong. Makes good sense if it's electric.

Nick

Hi Jackie,

I believe you can buy a box which fits on the end of a vent pipe which
has a filter in. I think these can be bought from somewhere like
Betterware if you know of it. One of these would allow you to vent the
dryer inside reserving the heat you are after.

"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket
of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased.
This
results in my windows in that part of the house fogging up when the dryer
has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had worked
out
in the long run. I heat with a natural gas forced air furnace. Thanks.



As you have discovered, it will warm your house but at the expense of excess
humidity. If you run one load a week, no problem but if you are washing
daily, I suspect that the ultimate cost of repairing moisture damage (curled
wallpaper, rotted window sills, discolored paint), the additional time
cleaning mildew and the cost of air freshners will outweigh the heating
savings you get.

Personally, I vent into my garage and use a screen as a lint trap which I
clean after each load just like the one in the dryer.

On 13 Feb 2006 13:17:34 -0500, wrote:

You might avoid this problem by venting the dryer into a plastic trash can
full of 2-liter water bottles, with a drain...


That sounds like a canned answer. ;-

--
-john
wide-open at throttle dot info

"Oscar_Lives" wrote in message
news:Eu5If.765626$x96.748634@attbi_s72...

"Joseph Meehan" wrote in message
news
Oscar_Lives wrote:
"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose
from blowing outside the house to inside and positioned it over a
small bucket of
water which acts as a lent trap. Now all that "paid for" warm air
stays inside but naturally the humidity level inside the house has
increased. This
results in my windows in that part of the house fogging up when the
dryer has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had
worked out
in the long run. I heat with a natural gas forced air furnace.
Thanks.



Stupid at best.

Dangerous and deadly at worst.

Follow your dryer's installation instructions. Never vent a dryer
indoors.

Note the OP wrote " I very recently have redirected my electric dryer
vent" Notice that is electric dryer. I would not say it was stupid or
generally dangerous. Had it been a gas dryer then it would have been
stupidly dangerous.

That said I would not do it myself, at least not likely. In fact if I
wanted to save on energy expense I would replace that electric dryer with
a gas dryer. In any case I don't like the idea. Even with one of the
"lint traps" very find lint still is going to find its way into your
home. That excessive moisture (condensation on the windows) can
contribute to mold and structural damage. Finally that lint filter can
cause increased back pressure and less efficiency for the dryer. I just
don't think the savings are worth the risks.


--
Joseph Meehan


I don't care if it is electric, gas, or heated by gerbils rubbing their
legs together, it is still stupid and also potentially dangerous to vent a
dryer inside.




Why, what mode of potentially dangerous failure presents itself?

As long as the dryer is not in a garage such that the vent passes through
the protective fire wall into the house it should be safe. (such a
configuration could also pump garage fumes into the house)

Sounds like the dryer is already in the house in some sort of laundry
closet.

On Mon, 13 Feb 2006 11:27:44 -0500, "Jackie"
wrote:

In an attempt to reduce my heating bills, and at the suggestion of a friend
of
mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased. This
results in my windows in that part of the house fogging up when the dryer
has been
running for an extended period but it does seem to dissipate fairly quickly.
I wondered if anyone else had tried this and whether or not it had worked
out
in the long run. I heat with a natural gas forced air furnace. Thanks.

I"ve been doing this for more than 20 years. No problems.

Physically in my case, it would be very difficult to disconnect and
connect the vent, and I didn't even think of it until I saw a diverter
box for sale that, after an initial installation, made this very easy.
It has a 4x4" louver that directs the air to the outside or to the
inside. No water bucket is involved but it does have a window screen
lint filter that the air passes through before it goes into the
basement. It takes several uses before it needs cleaning, and that's
undoubtedly because there is another lint filter in the dryer itself.
That one whistles when it needs cleaning, or at least when cleaning is
absolutely required (I forget which.). They sell a different model
diverter at Lowe's, I think it was, by the dryer accessories, a part
of store on the other side of the major appliances that I usually
don't walk through..

Generally indoor humdity is insufficient in the winter, especially or
at least iirc if one has forced air heat. Unless your situation is
different, iIt would be better to have a humidifier connected to the
furnace, because that could give adequate humidity all of the time.
The higher humitidy is good for wood furniture (that is, very low
humitidy is bad for it, leads to cracking), good for some people who
have certain respiratory problems iirc, and it also makes one feel
more comfortable, so that the thermostat can be set lower for the same
feeling of comfort.

FTR, I iive alone and don't use the dryer that much When I do use it,
I only use the temperature one notch above unheated air. The air
still seem quite hot to me. Some day I'll have to compare it to the
higher temperatures.

My impression is that hotter air is likely to remove the permanent
press feature of permanent press clothes, maybe permanently. The
shirts and pants certainly don't look good if they have gotten too
hot.

I put all of the permanent press in one load, and only dry one or two
absorbent items, like a towel or an item of underwear, at the same
time in order that the permanent press not dry too quickly. That is,
not dry completely before I have time to take it out.

I have a dryer that can turn off based on how damp the clothes are, so
I set it for a little less then totallly dry.I take the clothes out
then, because I think I get a better result that way. Although they
feel dry when they are warm, when they cool they feel damp a bit, but
p-press dries in just a few minutes.

Then usually I dry the remaining towels, socks, underwear,
sweatshirts, blue jeans, etc. separately, because they dry at the same
speed, and I usually take them out a bit early also and let them dry
from the shower bar. When I had a washer but no dryer, at my
previous apartment, I did all the drying this way, and the towels came
out rather stiff, but by the second use, they felt pretty much the
same as if they had been dried in a dryer.

(BTW, this house has no gas, but I doubt one would save money
switching to gas unless the dryer required replacement anyhow.)



Remove NOPSAM to email me. Please let
me know if you have posted also.

On Mon, 13 Feb 2006 19:55:16 GMT, "Oscar_Lives"
wrote:


I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

What is the danger with an electric dryer? Too much humidity? Too
much warmth? I give up.

Why is it stupid? Only because you think it is potentially dangerous,
or for some other reason?


Remove NOPSAM to email me. Please let
me know if you have posted also.

I want to thank everyone for the responses. I had hoped to generate a
discussion but had not anticipated such a divergence of opinion. My overall
impression is that my actions may have some merit as long as my dryer use is
not excessive. We probably do a couple of loads every other day. Of course I
considered safety issues before diverting the vent indoors and decided it
posed no threat since the dryer is no more than a large electric heater with
a blower fan. My plan is to try it for a while and keep a close eye on
things. If the indoor humidity becomes excessive or lint becomes a problem,
I can simply reattach the hose to the pipe venting outdoors. I plan to do
this in any event as soon as the weather warms up and it is my hope is that
winter does not linger for long here on the US eastern seaboard.

Also, thank you all for the suggestion on alternate ways to dry clothes as
well as other energy saving tips. Unfortunetly I am stuck with what I have
right now and will try to make the best of it. Sooner or later I know I will
need to replace my dryer and I will need to decide whether gas or electric
dryers are more efficent and cost effective at that time. I suppose I will
cross that bridge when I get to it. Thanks again.

On Mon, 13 Feb 2006 16:39:51 GMT, "Oscar_Lives"
wrote:


"Jackie" wrote in message
news:Ns2If.88567$4l5.75390@dukeread05...
In an attempt to reduce my heating bills, and at the suggestion of a
friend of
mine, I very recently have redirected my electric dryer vent hose from
blowing outside the house to inside and positioned it over a small bucket
of
water which acts as a lent trap. Now all that "paid for" warm air stays
inside but naturally the humidity level inside the house has increased.
This
results in my windows in that part of the house fogging up when the dryer
has been
running for an extended period but it does seem to dissipate fairly
quickly.
I wondered if anyone else had tried this and whether or not it had worked
out
in the long run. I heat with a natural gas forced air furnace. Thanks.




Stupid at best.

Why?

Dangerous and deadly at worst.


Why?
Follow your dryer's installation instructions. Never vent a dryer indoors.


Never vent a gas dryer indoors. Venting your electric dryer will

Add extra humidity to an otherwise wintery-dry house.
Reduce your heating costs.
Will add some lint to your air despite the water trap, so you may have
additional dusting chores.

On Mon, 13 Feb 2006 17:27:12 -0500, mm
wrote:

On Mon, 13 Feb 2006 19:55:16 GMT, "Oscar_Lives"
wrote:


I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

What is the danger with an electric dryer? Too much humidity? Too
much warmth? I give up.

Why is it stupid? Only because you think it is potentially dangerous,
or for some other reason?

Wow, dude! You just hung this poster out to dry!

--
-john
wide-open at throttle dot info

On Mon, 13 Feb 2006 19:18:20 -0800, ~^Johnny^~
wrote:

On Mon, 13 Feb 2006 17:27:12 -0500, mm
wrote:

On Mon, 13 Feb 2006 19:55:16 GMT, "Oscar_Lives"
wrote:


I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

What is the danger with an electric dryer? Too much humidity? Too
much warmth? I give up.

Why is it stupid? Only because you think it is potentially dangerous,
or for some other reason?

Wow, dude! You just hung this poster out to dry!

When we first got married, we lived in an apartment. I wanted to get
my wife a washer and dryer, but there was no place for them except in
the kitchen. There was no vent outlet for the electric dryer, and we
had to unplug the cooking range to plug it in. When we ran it, the
windows in the entire apartment looked like you turned hoses on them.
Water ran down the walls and on the floor. It was like we were in a
steam bath. The only way we could run the dryer was to open the door
and all the windows. It can be done, but it's not very smart.

mm wrote:

Generally indoor humdity is insufficient in the winter, especially or
at least iirc if one has forced air heat. Unless your situation is
different, iIt would be better to have a humidifier connected to the
furnace, because that could give adequate humidity all of the time.
The higher humitidy is good for wood furniture (that is, very low
humitidy is bad for it, leads to cracking), good for some people who
have certain respiratory problems iirc, and it also makes one feel
more comfortable, so that the thermostat can be set lower for the same
feeling of comfort.

But evaporating the water takes about 10X more heat energy
than you save with a lower thermostat setting.

Nick

On 2/13/06 4:14 PM, in article ,
" wrote:

Oscar_Lives wrote:

I don't care if it is electric, gas, or heated by gerbils rubbing their legs
together, it is still stupid and also potentially dangerous to vent a dryer
inside.

Wrong. Makes good sense if it's electric.

The exhaust from a dryer, electric or gas, comes from air blown over the
heating device. If a flame starts from lint blowing over the heating device,
that fire is ejected out the exhaust pipe. If there is anything flammable
anywhere near the exhaust, you've got yourself a homeowners claim at best
and you can guess the worst.

Oscar_Lives wrote:

Stupid at best.

Dangerous and deadly at worst.

Follow your dryer's installation instructions. Never vent a dryer indoors.

not too bright are you

you've probably had the same color car through 7 different cars
just a guess

I am a Certified Dryer Exhaust Technician. Most building codes require
that the dryer vent to the exterior of the structure due to fire hazard
issues. To say that "the dryer is no more than a large electric heater
with a blower fan" does not take into account the highly flammable lint
that is in the mixture. With the vent terminating inside, the lint
content of the air is increased and the home's air becomes a tinder box
that can ignite/explode with the right circumstances. Is this a good
trade-off for some heat reclamation? It's your home. You decide.

Michael Keefe wrote:

Oscar_Lives wrote:

... it is still stupid and also potentially dangerous to vent a dryer inside.

Wrong. Makes good sense if it's electric.

The exhaust from a dryer, electric or gas, comes from air blown over the
heating device. If a flame starts from lint blowing over the heating device,
that fire is ejected out the exhaust pipe...

The trash can full of 2-liter water bottles should
take care of that far-fetched possibility.

Nick

wrote in message
...
Michael Keefe wrote:

Oscar_Lives wrote:

... it is still stupid and also potentially dangerous to vent a dryer
inside.

Wrong. Makes good sense if it's electric.

The exhaust from a dryer, electric or gas, comes from air blown over the
heating device. If a flame starts from lint blowing over the heating
device,
that fire is ejected out the exhaust pipe...

The trash can full of 2-liter water bottles should
take care of that far-fetched possibility.

Nick

A properly maintained dryer with a thermal fuse that has not been jumpered
over will take care of that.

If it were a significant liability, manufacturers would not and might not be
allowed to sell plastic dryer vent bypass specifically for venting indoors,
their lawyers would put a stop to that. If dryers routinely turned into
blowtorches, I think some news magazine would be all over it.

As soon as ignition temp is reached (actually before) the thermal fuse is
supposed to blow and shut the whole thing down right away. Now if you let
Mickey Mouse fix your dryer, all bets are off.

On 14 Feb 2006 05:32:02 -0500, wrote:

mm wrote:

Generally indoor humdity is insufficient in the winter, especially or
at least iirc if one has forced air heat. Unless your situation is
different, iIt would be better to have a humidifier connected to the
furnace, because that could give adequate humidity all of the time.
The higher humitidy is good for wood furniture (that is, very low
humitidy is bad for it, leads to cracking), good for some people who
have certain respiratory problems iirc, and it also makes one feel
more comfortable, so that the thermostat can be set lower for the same
feeling of comfort.

But evaporating the water takes about 10X more heat energy
than you save with a lower thermostat setting.

A) This is not a situation where the person is evaporating water just
so she can heat the house. The water has already been evaporated,
and she wants to gain the side benefit of having that warm air and
humidity inside the house.

B) I think your last two lines above are inaccurate. I think it
takes 10 or so times as much heat to raise the temperature of water
one degreee when the water is also changing from liquid to gas, than
it does to raise the temperature of the water one degree without a
change of state. But the thermostat setting that is possible with
higher humidity is lower by more than one degree. I would say it's
possible to achieve the same degree of comfort with the thermostat set
5 degrees lower.




Although it was undesired, I have a lot of experience related to this.
When I lived in NY, I had a landlord who fancied himself a plumber.
He *was* capable of simple repairs, and of installing water-powered
trash compactors, and he had done those things for a living for some
years before buying my building and some others; but he was not
capable of maintaining the oil furnace steam heat that this 6-story
49-unit building had, (nor did he understand the water pressure issues
for a 6 story buidling on a hill.)

Because he fancied himself a plumber, he only called a skilled
repairman as a last resort. Consequently, we spent a lot more than
the typical number of days each winter without heat. I learned how
to "heat", that is, make feel comfortable, my 6-room apartment by
boiling water on the stove. Although I don't have numbers regarding
how much gas I used to boil the water for an hour (and I don't even
remember exactly how long I did so each time) I'm pretty sure the
effect on my comfort and my roommates' was far greater by boiling
water and increasing the humidity than the same gas would have been
just warming the air in the apartment. I believe there were a few
occasional stories on the news during the 12 years I lived in NY that
specifically said boiling water was far more effective. (and safer
because less gas had to be burned.)

Now that I own my own house, I bear a good portion of the blame any
time the furnace doesn't work. Never theless, there have been quite a
few days like this. I've used the shower (and a stoppered tub,
which I watch carefully to make sure it doesn't overflow) to raise the
humidity, and it takes no longer than running the furnace (up to a
point. I can make the house as hot as I want with the furnace, but
increased humdity can only do so much.) Remember to remove the bar
of soap before running the shower. I've wasted some soap when I
didn't remove it.

I've also boiled water on the stove in this house. I use a pot that
holds more than a gallon.

Both methods have had enormous effects on how comfortable I am when
the temperature in the house is 65 or 63 or even lower. That is, I
feel fine at those temperatures.

The OP only reported condensation on *some* of the windows in her
house, that part of the house where the dryer is, and that dissipated
quickly.

She doesn't have excess humidity and she's not going to hurt anything.

As to excess lint in the air, I've been doing this for 20+ winters,
and I haven't noticed anything. The dryer has a lint filter and my
diverter box has a second lint filter, that fills much more slowly
than the one in the dryer. Her device has some sort of filter too.
I clean my filters and I'm sure she does too.

I've never heard of a house fire where the air burnt because of the
lint in it, or where lint in the air was noticed to be burning. I've
never heard of a house fire where dust on the furniture or the mantle
was listed as one of the causes of the fire, or of the fire's
spreading. Maybe CDET22 can refer us to evidence of this.

But I can see the dust in my air when the sun is bright and shining in
the window, and it's no thicker in the winter than the summer, when I
vent the dryer outside and there is a breeze exchanging indoor air
with outdoor air.


Nick


Remove NOPSAM to email me. Please let
me know if you have posted also.

Well, this last post got my attention. I have never heard of a "Certified
Dryer Exhaust Technician" and didn't know there was such an animal but I
will take your word for it (that's just the kind of person I am). The last
thing I want to do is create a hazard in my home in order to save a few
bucks. As I have indicated I have a bucket of water trapping most of the
lint but before I abandon my venting scheme I am going to have to do a
little more research on the dangers of lint in the air. If this is such a
danger I wonder why you can purchase a kit specifically made for venting a
dryer indoors. Wouldn't that seem counterintuitive.

mm wrote:
wrote:
mm wrote:

Generally indoor humdity is insufficient in the winter, especially or
at least iirc if one has forced air heat. Unless your situation is
different, iIt would be better to have a humidifier connected to the
furnace, because that could give adequate humidity all of the time.
The higher humitidy is good for wood furniture (that is, very low
humitidy is bad for it, leads to cracking), good for some people who
have certain respiratory problems iirc, and it also makes one feel
more comfortable, so that the thermostat can be set lower for the same
feeling of comfort.

But evaporating the water takes about 10X more heat energy
than you save with a lower thermostat setting.

A) This is not a situation where the person is evaporating water just
so she can heat the house. The water has already been evaporated,
and she wants to gain the side benefit of having that warm air and
humidity inside the house.

Untrue, with the furnace humidifier.

B) I think your last two lines above are inaccurate.

I'm afraid you are incorrect, unless you live in an empty oil tank
with no insulation in Barrow, Alaska :-)

I think it takes 10 or so times as much heat to raise the temperature of water
one degreee when the water is also changing from liquid to gas, than
it does to raise the temperature of the water one degree without a
change of state.

Evaporating a pound of water takes 1000 Btu. Raising its temp 1 F takes 1 Btu.

But the thermostat setting that is possible with higher humidity is lower
by more than one degree. I would say it's possible to achieve the same
degree of comfort with the thermostat set 5 degrees lower.

I suggest you try actual numbers, including a house air leakage estimate.

Nick

The kits that are available that vent to a box specifically state that
they are to be used ONLY IF an exterior termination point is not
possible.
Dateline NBC did a story about the fire hazards involved with clothes
dryers and their lint.
The "blow torch" effect suggests a constant flow of fire. The lint
burns quickly and the amount of new lint fed to the flame is not enough
for a "blow torch' effect. The cubustible air content requires a high
concentration of lint in a closed-in area and a flash-point. This is
possible with continued use of an internally vented clothes dryer.
BTW, the Certified Dryer Exhaust Technician credential is awarded by
the Chimney Safety Institute of America.

On 15 Feb 2006 06:42:49 -0500, wrote:

mm wrote:
wrote:
mm wrote:

Generally indoor humdity is insufficient in the winter, especially or
at least iirc if one has forced air heat. Unless your situation is
different, iIt would be better to have a humidifier connected to the
furnace, because that could give adequate humidity all of the time.
The higher humitidy is good for wood furniture (that is, very low
humitidy is bad for it, leads to cracking), good for some people who
have certain respiratory problems iirc, and it also makes one feel
more comfortable, so that the thermostat can be set lower for the same
feeling of comfort.

But evaporating the water takes about 10X more heat energy
than you save with a lower thermostat setting.

A) This is not a situation where the person is evaporating water just
so she can heat the house. The water has already been evaporated,
and she wants to gain the side benefit of having that warm air and
humidity inside the house.

Untrue, with the furnace humidifier.

But true wrt the OP, which is the person I thought we were talking
about. . I did recommed a furnace humidifier, and a lot of other
people do too.

B) I think your last two lines above are inaccurate.

I'm afraid you are incorrect, unless you live in an empty oil tank
with no insulation in Barrow, Alaska :-)

I think it takes 10 or so times as much heat to raise the temperature of water
one degreee when the water is also changing from liquid to gas, than
it does to raise the temperature of the water one degree without a
change of state.

Evaporating a pound of water takes 1000 Btu. Raising its temp 1 F takes 1 Btu.

That's pretty much what I said, except that I thrrew in a 1 degree
rise in temp when it is evaporated. That's just the difference
between 9X and 10X.

But the thermostat setting that is possible with higher humidity is lower
by more than one degree. I would say it's possible to achieve the same
degree of comfort with the thermostat set 5 degrees lower.

I suggest you try actual numbers, including a house air leakage estimate.

Air leakage would be a separate issue.

I've been thinking about this more, and I'm pretty sure there were
specific statements on the news in NY that the city said that heating
the apartment with the stove was dangerous, and that boiling water was
safe and much more effective. I've done it many times, and that is my
conclusion too.

Nick


Remove NOPSAM to email me. Please let
me know if you have posted also.

mm wrote:

... It would be better to have a humidifier connected to the furnace...
the thermostat can be set lower for the same feeling of comfort.

But evaporating the water takes about 10X more heat energy
than you save with a lower thermostat setting...

I think it takes 10 or so times as much heat to raise the temperature of
water one degreee when the water is also changing from liquid to gas, than
it does to raise the temperature of the water one degree without a
change of state.

Evaporating a pound of water takes 1000 Btu. Raising it 1 F takes 1 Btu.

That's pretty much what I said, except that I thrrew in a 1 degree
rise in temp when it is evaporated. That's just the difference
between 9X and 10X.

Wrong, by a factor of 100. Raising a pound of 211 F water to 212 takes 1 Btu.
Evaporating the water takes about 1000 Btu. The ratio is 1001:1 vs 10:1.

... the thermostat setting that is possible with higher humidity is lower
by more than one degree. I would say it's possible to achieve the same
degree of comfort with the thermostat set 5 degrees lower.

The calc below shows the thermostat setpoint can only be lowered 0.74 F.

I suggest you try actual numbers, including a house air leakage estimate.

Air leakage would be a separate issue.

I disagree.

Nick
Article 93130 of alt.energy.homepower:
From:
Newsgroups: alt.home.repair,sci.engr.heat-vent-ac,misc.consumers.frugal-living
Subject: Winter humidification wastes energy
Date: 11 Feb 2005 08:33:11 -0500
Organization: Villanova University

Sent: Monday, January 17, 2005 8:58 AM

Subject: Attn: president/legal--Winter humidification wastes energy

Gentlemen,

I suspect that winter humidification wastes vs saves heating energy, and
the savings claim is an energy myth. People tend to forget that evaporating
water takes heat energy, and that heat energy has to come from somewhere,
even if something like a humidifier belt motor uses little energy by itself.

The heat saved by turning a thermostat down appears to be far less than
the extra heat used to evaporate water, in all but extremely tight houses
with little insulation, eg submarines.

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf claims
that 69 F at 35% RH and 72 F at 19% RH are equally comfortable, but the BASIC
program in the new ASHRAE 55-2004 comfort standard predicts that 69 F and 35%
RH and 69.7 at 19% RH are equally comfortable (PMV = -0.537, see below.)

If a 2400 ft^2 tight house has 0.5 ACH and say, 400 Btu/h-F of conductance,
turning the thermostat down from 69.7 to 69 saves (69.7-69)400 = 280 Btu/h.

Air at 69 F and 100% RH has humidity ratio w = 0.015832 pounds of water per
pound of dry air, so 19% air has wl = 0.00301, and 39% air has wh = 0.00617.
Raising 69 F air from 19 to 39% requires evaporating wh-wl = 0.00316 pounds
of water per pound of dry air. Dry air weighs about 0.075 lb per cubic foot.

With 0.5x2400x8/60 = 160 cfm or 9600 ft^3/h or 720 pounds per hour of
air leakage, raising the indoor RH from 19 to 39% requires evaporating
720x0.00316 = 2.275 pounds of water per hour, which requires about 2275
Btu/h of heat energy, so it looks like humidifying this fairly airtight
house wastes 2275/280 = 8 times more energy than it "saves." And many
US houses are less airtight, so humidification would waste more energy.

Please modify your energy-savings claim.

Thank you.

Nick Pine

10 SCREEN 9:KEY OFF
20 CLO=1'clothing insulation (clo)
30 MET=1.1'metabolic rate (met)
40 WME=0'external work (met)
50 DATA 69,35,69.74,19
60 FOR CASE=1 TO 2
70 READ TC,RC
80 TA=(TC-32)/1.8'air temp (C)
90 TR=TA'mean radiant temp (C)
100 VEL=.1'air velocity
110 RH=RC'relative humidity (%)
120 PA=0'water vapor pressure
130 DEF FNPS(T)=EXP(16.6536-4030.183/(TA+235))'sat vapor pressure, kPa
140 IF PA=0 THEN PA=RH*10*FNPS(TA)'water vapor pressure, Pa
150 ICL=.155*CLO'clothing resistance (m^2K/W)
160 M=MET*58.15'metabolic rate (W/m^2)
170 W=WME*58.15'external work in (W/m^2)
180 MW=M-W'internal heat production
190 IF ICL.078 THEN FCL=1+1.29*ICL ELSE FCL=1.05+.645*ICL'clothing factor
200 HCF=12.1*SQR(VEL)'forced convection conductance
210 TAA=TA+273'air temp (K)
220 TRA=TR+273'mean radiant temp (K)
230 TCLA=TAA+(35.5-TA)/(3.5*(6.45*ICL+.1))'est clothing temp
240 P1=ICL*FCL:P2=P1*3.96:P3=P1*100:P4=P1*TAA'intermed iate values
250 P5=308.7-.028*MW+P2*(TRA/100)^4
260 XN=TCLA/100
270 XF=XN
280 EPS=.00015'stop iteration when met
290 XF=(XF+XN)/2'natural convection conductance
300 HCN=2.38*ABS(100*XF-TAA)^.25
310 IF HCFHCN THEN HC=HCF ELSE HC=HCN
320 XN=(P5+P4*HC-P2*XF^4)/(100+P3*HC)
330 IF ABS(XN-XF)EPS GOTO 290
340 TCL=100*XN-273'clothing surface temp (C)
350 HL1=.00305*(5733-6.99*MW-PA)'heat loss diff through skin
360 IF MW58.15 THEN HL2=.42*(MW-58.15) ELSE HL2=0'heat loss by sweating
370 HL3=.000017*M*(5867-PA)'latent respiration heat loss
380 HL4=.0014*M*(34-TA)'dry respiration heat loss
390 HL5=3.96*FCL*(XN^4-(TRA/100)^4)'heat loss by radiation
400 HL6=FCL*HC*(TCL-TA)'heat loss by convection
410 TS=.303*EXP(-.036*M)+.028'thermal sensation transfer coefficient
420 PMV=TS*(MW-HL1-HL2-HL3-HL4-HL5-HL6)'predicted mean vote
430 PPD=100-95*EXP(-.03353*PMV^4-.2179*PMV^2)'predicted % dissatisfied
440 PRINT TC,RC,PMV
450 NEXT CASE

69 35 -.5376486
69.74 19 -.5372599

Engineering VP Mark Hogan said Lennox was embarrassed by all this and
he didn't know where their numbers had come from, and he thanked me
for bringing this to their attention and said they are changing their
printed brochures and Aprilaire web site energy-savings claim.

This reminds me of David and Goliath :-)

Nick