I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it on??
is there such as device? Help... please..

"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it on??
is there such as device? Help... please..

This is Turtle.

Yes there is a switch for this. It is called a Sall switch. It sticks out in the
duct and will lift up and turn on anything you want while the air is moving.
then when it stops the sall switch will cut it off.

Now you can use a isolation relay to do the same thing. It's nothing to set up.

TURTLE

"TURTLE" wrote
"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it
on??
is there such as device? Help... please..

This is Turtle.

Yes there is a switch for this. It is called a Sall switch. It sticks out
in the duct and will lift up and turn on anything you want while the air
is moving. then when it stops the sall switch will cut it off.

Now you can use a isolation relay to do the same thing. It's nothing to
set up.

(Turtle meant to say SAIL switch)

There is also a current sensing relay that is wrapped around the common wire
of the fan.

I can tell you though: Even if than little 24 volt motor (on the humidifier)
ran all day, it would probably use 1 ir 2 cents worth of electricity.....

nospamplease wrote:

I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

That's nothing, compared to the huge waste of heating fuel.

Nick

I owned a humidifier with a relay switch as described here, but the problem
was that the heater still didn't run long enough at one time to disburse
enough humidity to make the humidifier worthwhile. Before engineering a
clever on-off system, take some measurements of the average run time of your
blower on an average cold day (very difficult to do), and decide if that's
enough. At my house, running a hunidifier 30% of the time would be like not
having one. Then I got a standlone humidifier in my bedroom where I really
needed it, and that's another subject. It works best in a small area, so I
have to keep the bedroom and bathroom doors closed.
-B

"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it
on??
is there such as device? Help... please..

Stick that "current sensing relay" around the low speed blower motor lead
instead of the common wire. That way it will allow the humidifier to run
while in "heat" mode but not in "cool" mode. Assumes OP has central air, as
well.
"Red Neckerson" wrote in message
news:EY%kd.1253$fc.212@trnddc06...

"TURTLE" wrote
"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage.
However,
the humidifier is on even the heat is not on, the drum keeps rotating
all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it
on??
is there such as device? Help... please..

This is Turtle.

Yes there is a switch for this. It is called a Sall switch. It sticks
out
in the duct and will lift up and turn on anything you want while the air
is moving. then when it stops the sall switch will cut it off.

Now you can use a isolation relay to do the same thing. It's nothing to
set up.

(Turtle meant to say SAIL switch)

There is also a current sensing relay that is wrapped around the common
wire
of the fan.

I can tell you though: Even if than little 24 volt motor (on the
humidifier)
ran all day, it would probably use 1 ir 2 cents worth of electricity.....

Zypher repeats itself:

Humidifiers actually save fuel. The air temperature 'seems' warmer to
humans (creature comfort) if the humidity is high. Thus lower setting on
the thermostat.

Nonono. Repeating this won't make it so :-) Evaporating the water takes
far more energy than the lower thermostat setting saves.

The ASHRAE 55-2004 comfort standard says a 48x48x8' house with R20 walls
and ceiling would be equally comfy at 69.4 F and 20% RH or 68 F and 50% RH.
If it's very tight, with 0.5 air changes per hour, would humidification to
50% save energy?

G = 48'x48'/R20 + 48x4x8/R20 = 192 Btu/h-F, so dropping the room temp
from 69.4 to 68 F saves 1.4x192 = 269 Btu/h. At 69.4 F and 20% RH, Pd
= 0.2e^(17.863-9621/(460+69.4)) = 0.1466 "Hg, approximately, with wd
= 0.62198/(29.921/0.1466-1) = 0.003063. Air at 68 F and 50% RH has wh
= 0.007347. With 0.5x48x48x8/60 = 154 cfm of air leakage, humidifying
from wd to wh requires evaporating 154x60x0.075(wh-wd) = 2.96 pounds of
water per hour, which requires about 1000x2.96 = 2960 Btu/h of energy,
so the net "savings" is 2960-269 = -2691 Btu/h, or minus 64.6K Btu/day,
costing about $1/day more with oil heat or $2 per day with electric heat.

People tend to forget that evaporating water takes heat energy, even if
the "humidifier" uses little energy by itself, and that heat energy has
to come from somewhere. And we often get into discussions about health
and furniture, vs energy, and forget that caulking (vs humidification)
can raise the indoor RH while SAVING vs wasting more heating fuel.

Nick

Zypher wrote:

Humidifiers actually save fuel...

Nonono :-)

Nick

Hi Zypher, hope you are having a nice day

On 13-Nov-04 At About 03:31:39, Zypher wrote to Zypher
Subject: Humidifier Question

Z From: "Zypher"

Z Hi Nick;

Z Here's a link for you to read up on [albeit consumer literature but
Z it drives the point well.]

Z http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

it doesn't do any good to show him the truth. This guy is a legend in his
own mind and doesn't believe anything other then what he thinks.

-= HvacTech2 =-


... "I was up all night trying to round off infinity..." - s.w.

___ TagDude 0.92á+[DM]
++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++++++
spam protection measure, Please remove the 33 to send e-mail

Hi Nick;

Here's a link for you to read up on [albeit consumer literature but it
drives the point well.]

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

"Save energy and money - Because humidified air feels warmer, a humidifier
helps lower your heating bills. For example, a 69° temperature at 35%
relative humidity feels just as warm as a 72° setting at 19% relative
humidity."

--
Zyp
wrote in message
...
Zypher wrote:

Humidifiers actually save fuel...

Nonono :-)

Nick

Zypher wrote:

Hi Nick;

Hi Zypher,

Here's a link for you to read up on [albeit consumer literature but it
drives the point well.]

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

"Save energy and money - Because humidified air feels warmer, a humidifier
helps lower your heating bills. For example, a 69° temperature at 35%
relative humidity feels just as warm as a 72° setting at 19% relative
humidity."

The program in the ASHRAE 55-2004 comfort standard shows 69 F at 35%
is equivalent to 69.8 at 19%.

Lennox sells furnaces and humidifiers, and their statement above ignores
the heat energy needed to evaporate water, which is far more than the heat
energy saved with a lower thermostat setting.

Nick

I just purchased a Honeywell 260A (?) which comes with a sail switch and
30 VA transformer. I didn't want the hassle of cutting another hole in
the cold air return for the sail switch and running a 120VAC circuit to
the furnace for the transformer. However, I also didn't want to blow
the transformer on the furnace (Lennox G12, circa 1990).

I finally got through to a tech person at an HVAC dealership and he told
me that the transformers on furnaces are usually 40 VA, which is more
than the one that comes with the Honeywell.

Make sure you take a voltmeter and check which low-voltage terminals
supply 24VAC when the blower is running.

Of course, the humidifier would also run in the summer with this
configuration, but as long as you're using a humidistat set to 40% or
less, the relay will be open and prevent the humidifier from operating.

Zypher wrote:

Newer furnaces (since 1985) have on their circuit control board provisions
for humidifiers. But make sure the board humidifier terminals are for the
voltage(s) of the drum humidifier. (Some are 115 volt, and most are 24volt
controls.) Then the humidifier will only operate when the furnace is on.
(Not all furnaces have this feature though.)

Humidifiers actually save fuel. The air temperature 'seems' warmer to
humans (creature comfort) if the humidity is high. Thus lower setting on
the thermostat. Also, air that is 50% RH can harbor more heat per cubic
foot than air that is 30% RH for example.

wrote in message ...
Zypher wrote:

Hi Nick;

Hi Zypher,

Here's a link for you to read up on [albeit consumer literature but it
drives the point well.]

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

"Save energy and money - Because humidified air feels warmer, a humidifier
helps lower your heating bills. For example, a 69° temperature at 35%
relative humidity feels just as warm as a 72° setting at 19% relative
humidity."

The program in the ASHRAE 55-2004 comfort standard shows 69 F at 35%
is equivalent to 69.8 at 19%.

Lennox sells furnaces and humidifiers, and their statement above ignores
the heat energy needed to evaporate water, which is far more than the heat
energy saved with a lower thermostat setting.

Nick


Perhaps when Nick leaves egghead academia for the real world, he'll
travel and see the real world, instead of reading about it in books.
I suggest a trip to Las Vegas when it's 100 and quite comfortable,
followed by a trip to Georgia when it's 80 and feel's like hell. Then
maybe he will rethink his ideas.

I've installed a few drum type humidifiers, and each have been actuated
only when the fan for the furnace is running. Are you sure you installed it
correctly? With many furnaces, you can run the fan continuously, in which
case the humidifier may run continuously as well. Time to read your manuals.

Dave

"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it
on??
is there such as device? Help... please..

HvacTech2 wrote:

Z Here's a link for you to read up on...

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

it doesn't do any good to show him the truth. This guy is a legend in his
own mind and doesn't believe anything other then what he thinks.

It's surprising how little hvac installers know about physics and comfort.
You'd think they'd be curious, beyond the everyday nuts and bolts, or feel
some sense of responsibility.

We might try this in two steps:

1. The ASHRAE 55-2004 comfort standard says 69 F at 39% RH and 69.8 at 19%
are equally comfortable (PMV = -0.542.) Do you disagree with this?

2. Keeping a house 69 F at 39% RH uses more energy than keeping a house
69.8 at 19% in wintertime. Do you disagree with this?

If so, where are your calculations?

Nick

"Red Neckerson" wrote in message
news:EY%kd.1253$fc.212@trnddc06...

"TURTLE" wrote
"nospamplease" wrote in message
...
I bought the AirKing rotating drum type humidifier from home depot and
installed it on my furnace today, however, something I found it's very
stupid by design. I set the % humidity to my desired percentage. However,
the humidifier is on even the heat is not on, the drum keeps rotating all
the time. It's waste of my electricity.

Is it possible to install a device that detects air flow, then turns it on??
is there such as device? Help... please..

This is Turtle.

Yes there is a switch for this. It is called a Sall switch. It sticks out in
the duct and will lift up and turn on anything you want while the air is
moving. then when it stops the sall switch will cut it off.

Now you can use a isolation relay to do the same thing. It's nothing to set
up.

(Turtle meant to say SAIL switch)

There is also a current sensing relay that is wrapped around the common wire
of the fan.

I can tell you though: Even if than little 24 volt motor (on the humidifier)
ran all day, it would probably use 1 ir 2 cents worth of electricity.....

This is Turtle.

I don't have a Boat so I don't know how to sold.

TURTLE

"Joe Fabeitz" wrote in message
.. .
Stick that "current sensing relay" around the low speed blower motor lead
instead of the common wire. That way it will allow the humidifier to run
while in "heat" mode but not in "cool" mode. Assumes OP has central air, as
well.

This is Turtle.

How about putting it around the 115 volts going to the Fire Chamber vent fan
motor of the gas furnace and would only run in heat mode.

TURTLE

HvacTech2 wrote:

Z Here's a link for you to read up on...

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

it doesn't do any good to show him the truth. This guy is a legend in his
own mind and doesn't believe anything other then what he thinks.

It's surprising how little hvac installers know about physics and comfort.
You'd think they'd be curious, beyond the everyday nuts and bolts, or feel
some sense of responsibility.

We might try this in two steps:

1. The ASHRAE 55-2004 comfort standard says 69 F at 39% RH and 69.8 at 19%
are equally comfortable (PMV = -0.542.) Do you disagree with this?

2. Keeping a house 69 F at 39% RH uses more energy than keeping a house
69.8 at 19% in wintertime. Do you disagree with this?

If so, where are your calculations?

No disagreements? No calculations? :-) Let's try again, from the top:

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,
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 69.8 at 19% RH are equally comfortable (PMV = -0.542.)

If a 2400 ft^2 tight house has 0.5 ACH and say, 400 Btu/h-F of conductance,
turning the thermostat down from 69.8 to 69 saves (69.8-69)400 = 320 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.

Humid air seems healthier and may prevent furniture cracking and static
electricity, but serious air sealing seems like a better solution, with
blower door testing. Houses have natural humidity sources. Andersen says
an average family of 4 evaporates 2 gallons per day of water by breathing,
cleaning, cooking, and so on. Unlike humidification, more air sealing can
raise the RH while saving vs wasting heat energy.

Nick

Sure evaporating water wastes energy, but it is a matter of comfort,
static electricity, cracked wood etc. Plants and sealing the house can
do alot, but for most not enough.

I would like to see real calculations showing one way or the other.
That said, there are health reasons to humidify and there are health
reasons not to, if you don't clean the humidifier and let mold and
bacteria grow. But, back to the original question, a house that is very
leaky will cause the humidifier to run much more than a tight house.
Before I replaced my windows the humidifer would run all winter long (in
the Chicago area). With the new windows, it might run once during a
severe cold snap. Last winter is never ran. BTW, the windows were
replaced 10 or 12 years ago, so I have had many years to monitor this.
So, any calculations must take this into account also.

wrote:

HvacTech2 wrote:


Z Here's a link for you to read up on...

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf


it doesn't do any good to show him the truth. This guy is a legend in his
own mind and doesn't believe anything other then what he thinks.

It's surprising how little hvac installers know about physics and comfort.
You'd think they'd be curious, beyond the everyday nuts and bolts, or feel
some sense of responsibility.

We might try this in two steps:

1. The ASHRAE 55-2004 comfort standard says 69 F at 39% RH and 69.8 at 19%
are equally comfortable (PMV = -0.542.) Do you disagree with this?

2. Keeping a house 69 F at 39% RH uses more energy than keeping a house
69.8 at 19% in wintertime. Do you disagree with this?

If so, where are your calculations?


No disagreements? No calculations? :-) Let's try again, from the top:

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,
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 69.8 at 19% RH are equally comfortable (PMV = -0.542.)

If a 2400 ft^2 tight house has 0.5 ACH and say, 400 Btu/h-F of conductance,
turning the thermostat down from 69.8 to 69 saves (69.8-69)400 = 320 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.

Humid air seems healthier and may prevent furniture cracking and static
electricity, but serious air sealing seems like a better solution, with
blower door testing. Houses have natural humidity sources. Andersen says
an average family of 4 evaporates 2 gallons per day of water by breathing,
cleaning, cooking, and so on. Unlike humidification, more air sealing can
raise the RH while saving vs wasting heat energy.

Nick

You can say what you want about humidifiers, but I had an Aprilaire 600
installed on my new Carrier furnace return air duct and (my new ranch style
home is 2,880 sq feet) since I did my throat is not dry and sore every
morning I get up and I don't have hock my socks off to clear out my throat.
Also, static electricity has been eliminated in my home. I also think that
my gas bill will be cheaper with proper humidification. I disagree with you
who say home humidification is a farce. Of course one should not over
humidify and have their windows all steamed up and their walls dripping with
condensation. Common sense comes into play.


"Art Todesco" wrote in message
newsIpmd.104389$R05.64620@attbi_s53...
I would like to see real calculations showing one way or the other.
That said, there are health reasons to humidify and there are health
reasons not to, if you don't clean the humidifier and let mold and
bacteria grow. But, back to the original question, a house that is very
leaky will cause the humidifier to run much more than a tight house.
Before I replaced my windows the humidifer would run all winter long (in
the Chicago area). With the new windows, it might run once during a
severe cold snap. Last winter is never ran. BTW, the windows were
replaced 10 or 12 years ago, so I have had many years to monitor this.
So, any calculations must take this into account also.

wrote:

HvacTech2 wrote:


Z Here's a link for you to read up on...

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf


it doesn't do any good to show him the truth. This guy is a legend in
his
own mind and doesn't believe anything other then what he thinks.

It's surprising how little hvac installers know about physics and
comfort.
You'd think they'd be curious, beyond the everyday nuts and bolts, or
feel
some sense of responsibility.

We might try this in two steps:

1. The ASHRAE 55-2004 comfort standard says 69 F at 39% RH and 69.8 at
19%
are equally comfortable (PMV = -0.542.) Do you disagree with this?

2. Keeping a house 69 F at 39% RH uses more energy than keeping a house
69.8 at 19% in wintertime. Do you disagree with this?

If so, where are your calculations?


No disagreements? No calculations? :-) Let's try again, from the top:

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,
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 69.8 at 19% RH are equally comfortable (PMV
= -0.542.)

If a 2400 ft^2 tight house has 0.5 ACH and say, 400 Btu/h-F of
conductance,
turning the thermostat down from 69.8 to 69 saves (69.8-69)400 = 320
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.

Humid air seems healthier and may prevent furniture cracking and static
electricity, but serious air sealing seems like a better solution, with
blower door testing. Houses have natural humidity sources. Andersen says
an average family of 4 evaporates 2 gallons per day of water by
breathing,
cleaning, cooking, and so on. Unlike humidification, more air sealing
can
raise the RH while saving vs wasting heat energy.

Nick

wrote:

You can say what you want about humidifiers...

Thanks Ace. They waste energy.

I also think that my gas bill will be cheaper with proper humidification.

I disagree. Perhaps you have no understanding of physics.

I disagree with you who say home humidification is a farce.

I never said that. Perhaps you have no understanding of English :-)

Have a nice day.

Nick

On 16 Nov 2004 09:41:34 -0500, wrote:

HvacTech2 wrote:

Z Here's a link for you to read up on...

http://lennox.com/pdfs/brochures/Len...umidifiers.pdf

it doesn't do any good to show him the truth. This guy is a legend in his
own mind and doesn't believe anything other then what he thinks.

It's surprising how little hvac installers know about physics and comfort.
You'd think they'd be curious, beyond the everyday nuts and bolts, or feel
some sense of responsibility.

We might try this in two steps:

1. The ASHRAE 55-2004 comfort standard says 69 F at 39% RH and 69.8 at 19%
are equally comfortable (PMV = -0.542.) Do you disagree with this?

2. Keeping a house 69 F at 39% RH uses more energy than keeping a house
69.8 at 19% in wintertime. Do you disagree with this?

If so, where are your calculations?

No disagreements? No calculations? :-) Let's try again, from the top:

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,
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 69.8 at 19% RH are equally comfortable (PMV = -0.542.)

If a 2400 ft^2 tight house has 0.5 ACH and say, 400 Btu/h-F of conductance,
turning the thermostat down from 69.8 to 69 saves (69.8-69)400 = 320 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.

Humid air seems healthier and may prevent furniture cracking and static
electricity, but serious air sealing seems like a better solution, with
blower door testing. Houses have natural humidity sources. Andersen says
an average family of 4 evaporates 2 gallons per day of water by breathing,
cleaning, cooking, and so on. Unlike humidification, more air sealing can
raise the RH while saving vs wasting heat energy.

Nick


Since you seem to love math (I can do it but I hate it), let's give
you a little challenge:

Let's assume the same house. The indoor conditions are to be
maintained at 70F and 40% RH (because the homeowner likes it that
way). This translates to an indoor dewpoint temperature of about 44F.
When the outdoor dewpoint drops below 44F, that 160CFM of infiltration
air will need to be humidified, right?

But wait, we have our family of four providing 2 gallons per day of
humidity. Thus we can drop to a lower outdoor dewpoint before extra
humidification is needed for the infiltration air.

So here is the mission, should you choose to accept it:

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

What if the house were half the square footage (1200 sq ft)?

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Gary R. Lloyd wrote:

Let's assume the same house. The indoor conditions are to be
maintained at 70F and 40% RH (because the homeowner likes it that
way). This translates to an indoor dewpoint temperature of about 44F.

Td = 530/(1-530ln(0.4)/9621)-460 = 44.5. Pi =0.4e^(17.863-9621/530)
= 0.2994 "Hg... wi = 0.62198/(29.921/Pi-1) = 0.006286 pounds of water
per pound of dry air.

When the outdoor dewpoint drops below 44F, that 160CFM of infiltration
air will need to be humidified, right?

Somehow...

But wait, we have our family of four providing 2 gallons per day...

2x8.33/24/60 = 0.0116 lb/min.

Thus we can drop to a lower outdoor dewpoint before extra
humidification is needed for the infiltration air.

Sure.

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F.

What if the house were half the square footage (1200 sq ft)?

When 80x0.075(wi-wo) 0.0116, ie wo wi - 0.001933 = 0.004353 and Po
= 29.921/(0.62198/wo+1) = 0.2079 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 35.1 F, if it has half the air leakage.

Nick

I suggest we ignore the so-called no-it-all and if it makes one more
comfortable in ones home with the proper amount of humidification, and makes
one feel better physically, plus the other benefits it provides, go ahead
and do it! If Einstein does not believe in it that's his problem.

wrote in message
...
Gary R. Lloyd wrote:

Let's assume the same house. The indoor conditions are to be
maintained at 70F and 40% RH (because the homeowner likes it that
way). This translates to an indoor dewpoint temperature of about 44F.

Td = 530/(1-530ln(0.4)/9621)-460 = 44.5. Pi =0.4e^(17.863-9621/530)
= 0.2994 "Hg... wi = 0.62198/(29.921/Pi-1) = 0.006286 pounds of water
per pound of dry air.

When the outdoor dewpoint drops below 44F, that 160CFM of infiltration
air will need to be humidified, right?

Somehow...

But wait, we have our family of four providing 2 gallons per day...

2x8.33/24/60 = 0.0116 lb/min.

Thus we can drop to a lower outdoor dewpoint before extra
humidification is needed for the infiltration air.

Sure.

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F.

What if the house were half the square footage (1200 sq ft)?

When 80x0.075(wi-wo) 0.0116, ie wo wi - 0.001933 = 0.004353 and Po
= 29.921/(0.62198/wo+1) = 0.2079 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 35.1 F, if it has half the air leakage.

Nick

On 17 Nov 2004 11:10:51 -0500, wrote:

Gary R. Lloyd wrote:

Let's assume the same house. The indoor conditions are to be
maintained at 70F and 40% RH (because the homeowner likes it that
way). This translates to an indoor dewpoint temperature of about 44F.

Td = 530/(1-530ln(0.4)/9621)-460 = 44.5. Pi =0.4e^(17.863-9621/530)
= 0.2994 "Hg... wi = 0.62198/(29.921/Pi-1) = 0.006286 pounds of water
per pound of dry air.

When the outdoor dewpoint drops below 44F, that 160CFM of infiltration
air will need to be humidified, right?

Somehow...

But wait, we have our family of four providing 2 gallons per day...

2x8.33/24/60 = 0.0116 lb/min.

Thus we can drop to a lower outdoor dewpoint before extra
humidification is needed for the infiltration air.

Sure.

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F.

What if the house were half the square footage (1200 sq ft)?

When 80x0.075(wi-wo) 0.0116, ie wo wi - 0.001933 = 0.004353 and Po
= 29.921/(0.62198/wo+1) = 0.2079 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 35.1 F, if it has half the air leakage.

Nick


Hmmmmm... Considering that our family of 4 needs 15CFM of fresh air
each, for a total of 60CFM, I don't think we want to tighten a house
up much more than that.

Just for a rough rule of thumb:

It seems that when outdoor temps start dipping below freezing at
night, our options are to humidify or to accept lower indoor humidity.

On the other hand, if our humidity drops below 40% before the outdoor
temps drop below freezing at night, then we need to seal up the house.

Does that sound about right?

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Gary R. Lloyd wrote:

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F...

Considering that our family of 4 needs 15CFM of fresh air each... I don't
think we want to tighten a house up much more than that.

I think we do, with positive ventilation as needed.

Nick

On 17 Nov 2004 20:03:44 -0500, wrote:

Gary R. Lloyd wrote:

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F...

Considering that our family of 4 needs 15CFM of fresh air each... I don't
think we want to tighten a house up much more than that.

I think we do, with positive ventilation as needed.

Nick


When it comes to something as vital as providing sufficient air to
breathe, I would lean heavily towards passive solutions and overkill,
i.e. leakage. It's about human health and comfort. Screw the energy
efficiency.

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

Besides, my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Art Todesco wrote:

I would like to see real calculations showing one way or the other.

You've seen 'em.

Nick

Gary R. Lloyd wrote:

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F.

It seems that when outdoor temps start dipping below freezing at night,
our options are to humidify or to accept lower indoor humidity.

I wonder why you wrote that. Another option is air sealing to raise the RH.
BTW, we've only discussed the outdoor dewpoint (vs. dry bulb) temperature.

On the other hand, if our humidity drops below 40% before the outdoor
temps drop below freezing at night, then we need to seal up the house.

Air sealing is good in any case. "Make it tight, and vent it right."

Nick

Gary R. Lloyd wrote:

When it comes to something as vital as providing sufficient air to
breathe, I would lean heavily towards passive solutions and overkill,
i.e. leakage. It's about human health and comfort. Screw the energy
efficiency.

Spoken like an HVAC criminal :-) But we can enjoy "human health and
comfort" with less energy consumption if we do air sealing first.
It would be extraordinarily difficult to seal up a house so tight
that a person could not breathe. And most people would open windows
as needed to avoid condensation and lower the indoor RH. That's also
easy to do with a small exhaust fan and a humidistat.

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence? Then again,
living with low humidity is only one option. It's better to raise
the RH and lower the fuel bill with more air sealing.

Besides, my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Nick

On 18 Nov 2004 09:40:18 -0500, wrote:

Gary R. Lloyd wrote:

When it comes to something as vital as providing sufficient air to
breathe, I would lean heavily towards passive solutions and overkill,
i.e. leakage. It's about human health and comfort. Screw the energy
efficiency.

Spoken like an HVAC criminal :-) But we can enjoy "human health and
comfort" with less energy consumption if we do air sealing first.

Show me.

It would be extraordinarily difficult to seal up a house so tight
that a person could not breathe. And most people would open windows
as needed to avoid condensation and lower the indoor RH. That's also
easy to do with a small exhaust fan and a humidistat.

Seal up the house and then open the window? Oddly enough, I think
that's what a lot of people do.

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence?

I have no intention of proving anything.

Then again,
living with low humidity is only one option. It's better to raise
the RH and lower the fuel bill with more air sealing.

Actually, I'm a big fan of sealing up the house, but I draw the line
at putting a plastic bag over people's heads.

Besides, my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Let's try to stay on subject, shall we?

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

On 18 Nov 2004 09:17:10 -0500, wrote:

Gary R. Lloyd wrote:

At what outdoor dewpoint temperature do we need to start adding
moisture in order to maintain our 70F and 40% RH?

When 160x0.075(wi-wo) 0.0116, ie wo wi - 0.000966 = 0.005319 and Po
= 29.921/(0.62198/wo+1) = 0.2357 "Hg and Td = 9621/(17.863-ln(Pi))-460
= 40.2 F.

It seems that when outdoor temps start dipping below freezing at night,
our options are to humidify or to accept lower indoor humidity.

I wonder why you wrote that. Another option is air sealing to raise the RH.
BTW, we've only discussed the outdoor dewpoint (vs. dry bulb) temperature.

Hence calling it a rough rule of thumb.

On the other hand, if our humidity drops below 40% before the outdoor
temps drop below freezing at night, then we need to seal up the house.

Air sealing is good in any case. "Make it tight, and vent it right."

To a point.

Our energy-is-all-that-matters geniuses have given us lots of
unintended consequences, such as sick buildings and enormous mold
problems (which they are trying to blame on contractors). What next?
As far as I am concerned, they are fast losing their credibility.

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Gary R. Lloyd wrote:

When it comes to something as vital as providing sufficient air to
breathe, I would lean heavily towards passive solutions and overkill,
i.e. leakage. It's about human health and comfort. Screw the energy
efficiency.

Spoken like an HVAC criminal :-) But we can enjoy "human health and
comfort" with less energy consumption if we do air sealing first.

Show me.

Done that, several times now.

It would be extraordinarily difficult to seal up a house so tight
that a person could not breathe. And most people would open windows
as needed to avoid condensation and lower the indoor RH. That's also
easy to do with a small exhaust fan and a humidistat.

Seal up the house and then open the window? Oddly enough, I think
that's what a lot of people do.

Oh?

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence?

I have no intention of proving anything.

Good idea. Perhaps you recall your last attempt at proving something,
in which you confused dew point and wet bulb temps :-)

...my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Let's try to stay on subject, shall we?

People are different. Avoiding Middle-East wars is a primary motivation
for using less fossil fuels, in my case.

Nick

On Thu, 18 Nov 2004 16:20:52 GMT, (Gary R. Lloyd) wrote:

Actually, I'm a big fan of sealing up the house


I see a pun here, but I will desist. :-)

You both have valid arguments.
But I agree, caulking generally doesn't do **** for infiltration control.

Caulking and weatherstripping has to be evaluated on a case-by-case basis,
but generally, it is a marketing ploy.

I don't keep my doors and windows shut 24/7.


--
-john
wide-open at throttle dot info

On 18 Nov 2004 18:02:29 -0500, wrote:

Gary R. Lloyd wrote:

When it comes to something as vital as providing sufficient air to
breathe, I would lean heavily towards passive solutions and overkill,
i.e. leakage. It's about human health and comfort. Screw the energy
efficiency.

Spoken like an HVAC criminal :-) But we can enjoy "human health and
comfort" with less energy consumption if we do air sealing first.

Show me.

Done that, several times now.

You forgot to show me the health and comfort part.

It would be extraordinarily difficult to seal up a house so tight
that a person could not breathe. And most people would open windows
as needed to avoid condensation and lower the indoor RH. That's also
easy to do with a small exhaust fan and a humidistat.

Seal up the house and then open the window? Oddly enough, I think
that's what a lot of people do.

Oh?

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.

Is this an example of showing me?

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence?

I have no intention of proving anything.

Good idea. Perhaps you recall your last attempt at proving something,
in which you confused dew point and wet bulb temps :-)

I didn't confuse anything. I offered a rough rule of thumb based on
DB, and said it was a rough rule of thumb.

...my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Let's try to stay on subject, shall we?

People are different. Avoiding Middle-East wars is a primary motivation
for using less fossil fuels, in my case.

Wars are a diversionary tactic. "LOOK OVER THERE. ITS A WAR"
(insert hand remove wallet)

Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Gary R. Lloyd wrote:

...we can enjoy "human health and comfort" with less energy
consumption if we do air sealing first.

Show me.

Done that, several times now.

You forgot to show me the health and comfort part.

That's your job, as a higher-humidity proponent. You've seen the comfort
part (ASHRAE 55-2004) several times now. I'm not sure health has much
to do with low humidity. At any rate, unlike mechanical humidification,
air sealing can raise humidity while lowering vs raising fuel bills.

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.

Is this an example of showing me?

No. This is an example of humor.

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence?

I have no intention of proving anything.

Good idea. Perhaps you recall your last attempt at proving something,
in which you confused dew point and wet bulb temps :-)

I didn't confuse anything. I offered a rough rule of thumb based on
DB, and said it was a rough rule of thumb.

That was this time. Last time (in August of 2002) you confused dew point
and wet bulb temps. It's surprising how little hvac "tech method gurus"
know about physics.

...my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Let's try to stay on subject, shall we?

People are different. Avoiding Middle-East wars is a primary motivation
for using less fossil fuels, in my case.

Wars are a diversionary tactic. "LOOK OVER THERE. ITS A WAR"

Chacun a sa guerre.

http://dailydig.bruderhof.org/us/TodaysDig.htm

Nick

On 19 Nov 2004 07:32:20 -0500, wrote:

Gary R. Lloyd wrote:

...we can enjoy "human health and comfort" with less energy
consumption if we do air sealing first.

Show me.

Done that, several times now.

You forgot to show me the health and comfort part.

That's your job, as a higher-humidity proponent. You've seen the comfort
part (ASHRAE 55-2004) several times now. I'm not sure health has much
to do with low humidity. At any rate, unlike mechanical humidification,
air sealing can raise humidity while lowering vs raising fuel bills.

You are the one who wants to seal people up in a bubble and pump in
the air. It is up to you to show us that it is healthy and foolproof.

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.

Is this an example of showing me?

No. This is an example of humor.

As was my response to it.

People in dry climates are acclimated to their environment, and thus
would have no problem with low humidity. People who suffer through
high temperature and humidity throughout the summer are not equipped
to put up with low humidity in the winter.

In what sense? How do you know? Where is your evidence?

I have no intention of proving anything.

Good idea. Perhaps you recall your last attempt at proving something,
in which you confused dew point and wet bulb temps :-)

I didn't confuse anything. I offered a rough rule of thumb based on
DB, and said it was a rough rule of thumb.

That was this time. Last time (in August of 2002) you confused dew point
and wet bulb temps. It's surprising how little hvac "tech method gurus"
know about physics.

The two are close enough to be considered the same for practical
purposes, but then you are not concerned with what is practical, so we
can't expect you to understand.

...my grandmother's antique dining room set doesn't like low
humidity, so that settles it.

Is it better to airseal your house to assuage the feelings of your
grandmother's antique dining room set, or humidify the house and
dramatically increase the fuel bill and invade Iran to keep the price
of oil low? :-)

Let's try to stay on subject, shall we?

People are different. Avoiding Middle-East wars is a primary motivation
for using less fossil fuels, in my case.

Wars are a diversionary tactic. "LOOK OVER THERE. ITS A WAR"

Chacun a sa guerre.

http://dailydig.bruderhof.org/us/TodaysDig.htm

Funny article. Well written.


Gary R. Lloyd CMS
HVACR Troubleshooting Books/Software
http://www.techmethod.com

Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.


Low tech way of getting humidity into the air and saving on heating
bills!

A pan of water near the heating duct .......... over it, under it,
whatever ...... near it.

Joel


Is this an example of showing me?

No. This is an example of humor.

On Fri, 19 Nov 2004 09:36:21 -0500, Joel M. Eichen
wrote:



Herbach and Rademan (800) 848-8001 http://www.herbach.com sell a nice
brass $4.95 Navy surplus humidistat, item number TM89HVC5203, with a
20-80% range, a 3-6% differential, and a 7.5A 125V switch that can be
wired to open or close on humidity rise.

And if the control fails?

We suffocate like dogs.


Low tech way of getting humidity into the air and saving on heating
bills!

A pan of water near the heating duct .......... over it, under it,
whatever ...... near it.

Joel

Some people just toss their towel over the rail where the forced air
can dry it out nicely ... Makes it nice and toasty for the next shower
too!

Dentists use hot towel warmers but this is better ......


Joel




Is this an example of showing me?

No. This is an example of humor.