Alternative Power sources - Dehumidifier power

Author

Dehumidifier power

Nottnick

2006-07-24, 9:25 am

In UK

Have drum room in cellar.
Need dehumidifier to keep air dry.
Current model rating = 400W Max 16 litres/day.

Currently extracts about 0.7 litres / day. (so not working itself too hard)

However it is running most of the time = quite a lot of money per month.

Is there a more cost effective method?

Advice appreciated.

Nick

Anthony Matonak

2006-07-24, 9:25 am

Nottnick wrote:
> Have drum room in cellar.
> Need dehumidifier to keep air dry.
> Current model rating = 400W Max 16 litres/day.
> Currently extracts about 0.7 litres / day. (so not working itself too hard)
> However it is running most of the time = quite a lot of money per month.
> Is there a more cost effective method?

Perhaps you could add an external humidistat to only turn
the unit on when the humidity exceeds a certain level.

An alternative would be to use a desiccant, like silica gel,
that is available in bulk. Every so often you'll need to
"recharge" it, typically by baking. This baking/drying step
could be done in a solar oven or solar dehumidifier.

If you want to go completely automated you could use desiccant
discs like they use for building cooling. They slowly spin
between two chambers that have air flowing through them. The
one chamber has heated air that dries the desiccant and the
other has air that is dehumidified. The heat could be supplied
by a solar thermal collector of some sort. If you want it to
work when the sun doesn't shine you could use some kind of
burner (natural gas, propane, wood).

Anthony

Mary Fisher

2006-07-24, 9:25 am

"Nottnick" <nmmnews@bellows.org.uk> wrote in message
news:ka-dncBz17-rFFnZnZ2dnUVZ8tydnZ2d@bt.com...
> In UK
>
> Have drum room in cellar.
> Need dehumidifier to keep air dry.
> Current model rating = 400W Max 16 litres/day.
>
> Currently extracts about 0.7 litres / day. (so not working itself too
> hard)
>
> However it is running most of the time = quite a lot of money per month.
>
> Is there a more cost effective method?
>
> Advice appreciated.
>
> Nick

A relative humidity controlled, low wattage, low noise, extractor fan might
be an answer.

Low running cost and only works when the air is damp - unless you prefer to
use it any other way.

We have a Vent-Axia 459051 low watt fan with humidistat in our bathroom and
are very well pleased. They have an enormous range of equipment and would
probably be able to advise for your specific problem.

From their site:
The Technical Service Department is available for your calls from 8:45 to
17:00 BST, Monday to Thursday and 8:45 to 16.30 BST Friday, providing best
practice installation and product selection advice over the phone. Using the
latest information systems our Technical Support Team members can instantly
fax or e-mail you product information, typical application drawings or
specific wiring diagrams.
All technical enquiries
Tel: +44 (0)1293 526 062 Domestic and Commercial Support
Tel: +44 (0)1293 455 196 Industrial Support
Fax: +44 (0)1293 551 188
e-mail: tech@vent-axia.com

We found them very helpful and eventually bought our fan from a local
supplier.

Mary
Leeds, Yorkshire
>
>
>

nicksanspam@ece.villanova.edu

2006-07-24, 9:25 am

Nottnick <nmmnews@bellows.org.uk> wrote:

>Have drum room in cellar.
>Need dehumidifier to keep air dry.
>Current model rating = 400W Max 16 litres/day.
>
>Currently extracts about 0.7 litres / day. (so not working itself too hard)
>
>However it is running most of the time = quite a lot of money per month.
>
>Is there a more cost effective method?

Yes. Ventilate with outdoor air when its vapor pressure
is less than the basement air vapor pressure.

Nick

nicksanspam@ece.villanova.edu

2006-07-24, 9:25 am

Mary Fisher <mary.fisher@zetnet.co.uk> wrote:
>
>"Nottnick" <nmmnews@bellows.org.uk> wrote in message
>
>A relative humidity controlled, low wattage, low noise, extractor fan might
>be an answer.

If the basement air and the outdoor air were the same temperature, we might
ventilate when the basement air has a higher RH. We might make equal temps
by caulking a thin foamboard box to a basement window, with small holes at
the top and bottom to let a little basement air flow through the box and
warm to the outdoor temp through the low thermal resistance of the glass.
We might have one RH sensor in the box and another RH sensor outdoors.

Nick

Nick Hull

2006-07-24, 9:25 am

In article <ka-dncBz17-rFFnZnZ2dnUVZ8tydnZ2d@bt.com>,
"Nottnick" <nmmnews@bellows.org.uk> wrote:

> In UK
>
> Have drum room in cellar.
> Need dehumidifier to keep air dry.
> Current model rating = 400W Max 16 litres/day.
>
> Currently extracts about 0.7 litres / day. (so not working itself too hard)
>
> However it is running most of the time = quite a lot of money per month.
>
> Is there a more cost effective method?
>
> Advice appreciated.
>
> Nick
>
>
>

An air conditioner is usually more efficient at dehumidifying than a
dehumidifier.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

Mary Fisher

2006-07-24, 9:25 am

"Nick Hull" <nhull@access4less.net> wrote in message
news:nhull-F2514F.03504624072006@news.west.earthlink.net...
>
> An air conditioner is usually more efficient at dehumidifying than a
> dehumidifier.

And frightfully power hungry.

Mary

JoeSP

2006-07-24, 9:25 am

samc

2006-07-24, 9:25 am

Nottnick wrote:
> In UK
>
> Have drum room in cellar.
> Need dehumidifier to keep air dry.
> Current model rating = 400W Max 16 litres/day.
>
> Currently extracts about 0.7 litres / day. (so not working itself too hard)
>
> However it is running most of the time = quite a lot of money per month.
>
> Is there a more cost effective method?
>
> Advice appreciated.
>
> Nick
>
>
>
there are 2 main systems for stopping damp/flooding in cellar's .
(1) a vapour barrour is placed on the walls/floor with a sump in the
center of the floor for the water to be extracted with a pump .
(2) the earth is dug away from the sides of the cellar out side and a
inpervious barryour is appleyd to the out side walls .
prob not what you wanted to hear I know .

Nottnick

2006-07-24, 1:25 pm

Yea I knew that was the case. We are just making the best of things -
hopefully cheaper to pay for power than all tanking work (although as I
said, power isn't so cheap!!).

"samc" <remprefix.samuel.7scrubthis9@tiscali.co.uk> wrote in message
news:44c4c039$1_2@mk-nntp-2.news.uk.tiscali.com...
> Nottnick wrote:
> there are 2 main systems for stopping damp/flooding in cellar's .
> (1) a vapour barrour is placed on the walls/floor with a sump in the
> center of the floor for the water to be extracted with a pump .
> (2) the earth is dug away from the sides of the cellar out side and a
> inpervious barryour is appleyd to the out side walls .
> prob not what you wanted to hear I know .

Nottnick

2006-07-24, 1:25 pm

"JoeSP" <olegp@telus.net> wrote in message
news:db3xg.127926$I61.27937@clgrps13...
>
> "Nottnick" <nmmnews@bellows.org.uk> wrote in message
> news:ka-dncBz17-rFFnZnZ2dnUVZ8tydnZ2d@bt.com...
>
> Atmospheric humidity is a variable. One day it might extract 16 litres,
> and it might be 0.7 the next. A humidistat and a few bags of dessicant
> should do the trick. Is there a steady flow of humid air into the room?
> Reduce it if you can.

Hi Joe

So I just buy loads of dessicant and re-charge it regularly.
How much dessicant?

Any thoughts as to what is reasonable humidity to try to obtain? I have a
digital weather gizmo in front of me right now and it gives humidity as a
percentage (44% in my study at the moment).

Only air flow is through 2 air bricks and I think I need to have a bit of
air flow available (or maybe not?).
Thanks

Nick

>

JoeSP

2006-07-24, 1:25 pm

"Nottnick" <nmmnews@bellows.org.uk> wrote in message
news:6PCdnWfFKvADnVjZRVnyrg@bt.com...
>
> "JoeSP" <olegp@telus.net> wrote in message
> news:db3xg.127926$I61.27937@clgrps13...
>
> Hi Joe
>
> So I just buy loads of dessicant and re-charge it regularly.
> How much dessicant?
>
> Any thoughts as to what is reasonable humidity to try to obtain? I have a
> digital weather gizmo in front of me right now and it gives humidity as a
> percentage (44% in my study at the moment).
>
> Only air flow is through 2 air bricks and I think I need to have a bit of
> air flow available (or maybe not?).
> Thanks
>
> Nick

The cheapest way I know is to use rock salt in burlap sacks. Every few
months, you can change them out. As long as your airflow isn't excessive,
it should keep the air fairly dry. The best way to measure humidity is with
a wet-dry bulb humidity meter.

Neon John

2006-07-24, 8:25 pm

Before you go off on this ill-advised tangent, consider the physics
and do a little math. See how much desiccant it's going to take to
remove even one gallon per day and then figure up the work involved in
rejuvenating it every day or two. Then, of course, there's the
energy. It takes more than the heat of vaporization of water to drive
it from the desiccant so the energy consumption will actually be
higher than with a high efficiency refrigeration-type dehumidifier.

You really only have two options - refrigeration-based
dehumidification and ventilation. The second option is only available
if there is a source of dry air available. If the outside air is as
humid as indoors then ventilation will do you no good.

It takes a relatively large amount of energy to dehumidify simply
because water has such a high heat of vaporization. That heat has to
be absorbed to condense the water vapor into liquid water. That's
something we're stuck with. The only way to reduce the power
consumption is to find a more efficient refrigeration unit and/or
reduce the moisture influx.

You may find as I did that a high SEER window AC is more efficient
than a typical dehumidifier. I found that an 8000 BTU 11 SEER window
unit was considerably more efficient than any dehumidifier available
on the local market AND it removed much more water AND it was a LOT
cheaper (about $90 vs over $200 for typical dehumidifier). I have it
sitting on a platform over the floor drain in my basement. I drilled
a hole in the bottom to let the condensate drain to the floor drain
and blocked the little tube that normally carries the condensate to
the condenser to be evaporated outside. I have an external humidistat
wired to the unit to turn it off in the unlikely event it ever dries
the basement below 50% RH.

The way to evaluate the efficiency is in terms of water removed per
unit of energy. That would normally be grams/ounces/gallons of water
per kilowatt-hour. The nameplate power consumption is, in my
experience, usually higher than actual. Actually measuring the power
consumption using a Kill-a-Watt (KAW) or equiv is the way to
accurately determine efficiency.

When I was choosing my AC unit, I carried my KAW to the various stores
and actually operated each unit under consideration.

There is one limitation to using an AC and that is the limit of
humidity reduction. ACs are designed to never bring the evaporator
below freezing and typically don't go below about 38 degs. That means
that the humidity can't go below about 40 deg wet bulb which is about
38% RH for a dry bulb temperature of 70 degrees. If you need to go
below that you'll have to get a freezing dehumidifier. This type of
dehumidifier is designed to freeze the evaporator and periodically
thaw it. Only go that route if you need the lower humidity, for the
freezing style is a little less efficient.

The best return on investment will be dollars spent reducing the
moisture influx. Sealing the concrete floor and walls, for instance,
can dramatically reduce the moisture that diffuses through them.

As part of my moisture reduction program I had the dirt next to the
house dug out to below the foundation, coated the blocks with tar and
black poly, installed a french drain and backfilled a foot or two with
gravel before replacing the dirt. I also graded the fill away from
the house to ensure that rain water didn't flow back against the
walls. I painted the inside walls with that water sealer paint that
the home improvement stores sell and I coated the floor with cement
floor paint.

It is far too humid to rely on ventilation where I live so the
moisture reduction program and the dehumidifier were the techniques
necessary. My basement went from having billowing growths of mildew
and other fungus growing on the floor studs to being pretty much as
dry as the house.

John

On Mon, 24 Jul 2006 18:17:16 +0100, "Nottnick"
<nmmnews@bellows.org.uk> wrote:

>
>"JoeSP" <olegp@telus.net> wrote in message
>news:db3xg.127926$I61.27937@clgrps13...
>
>Hi Joe
>
>So I just buy loads of dessicant and re-charge it regularly.
>How much dessicant?
>
>Any thoughts as to what is reasonable humidity to try to obtain? I have a
>digital weather gizmo in front of me right now and it gives humidity as a
>percentage (44% in my study at the moment).
>
>Only air flow is through 2 air bricks and I think I need to have a bit of
>air flow available (or maybe not?).
>Thanks
>
>Nick
>
>
>
>
---
John De Armond
See my website for my current email address
http://www.neon-john.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain

Nick Hull

2006-07-25, 9:25 am

In article <44c4b6a8$0$904$4c56ba96@master.news.zetnet.net>,
"Mary Fisher" <mary.fisher@zetnet.co.uk> wrote:

> "Nick Hull" <nhull@access4less.net> wrote in message
> news:nhull-F2514F.03504624072006@news.west.earthlink.net...
>
> And frightfully power hungry.

For equal power an AC is better at dehumidifying than a dehumidifier

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

Mary Fisher

2006-07-25, 9:25 am

"Nick Hull" <nhull@access4less.net> wrote in message
news:nhull-210907.03140325072006@news.west.earthlink.net...
> In article <44c4b6a8$0$904$4c56ba96@master.news.zetnet.net>,
> "Mary Fisher" <mary.fisher@zetnet.co.uk> wrote:
>
>
> For equal power an AC is better at dehumidifying than a dehumidifier

Still frightfully power hungry.

Mary
>

Mary Fisher

2006-07-25, 9:25 am

Neon John

2006-07-25, 1:25 pm

On Tue, 25 Jul 2006 12:02:11 +0100, "Mary Fisher"
<mary.fisher@zetnet.co.uk> wrote:

>
>"Nick Hull" <nhull@access4less.net> wrote in message
>news:nhull-210907.03140325072006@news.west.earthlink.net...
>
>Still frightfully power hungry.

Actually, no, it isn't. While consuming more power while running, for
a given amount of water removal, the AC unit will run fewer hours.
Overall, therefore, the unit is actually LESS power hungry (whatever
that scientific term means) than the dehumidifier.

Regarding energy cost, unless you're a commercial customer on demand
billing, the RATE of power use has no effect on the bill. It is the
total number of KHW that matters and a high efficiency AC unit will
use fewer of those to do a given job than typical dehumidifier.

John
---
John De Armond
See my website for my current email address
http://www.neon-john.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain

John

2006-07-25, 5:25 pm

If your unit is not working at rated capacity you might want to open the
thing up and check the coils for dust and dirt build up. Most dont have
filters on them.I have found several that were thrown away and that was
all that was wrong with them

Nottnick

2006-07-26, 9:25 am

"Neon John" <no@never.com> wrote in message
news:ejkac2d2iikjj96f61qrdprq339c4ugkub@4ax.com...
> Before you go off on this ill-advised tangent, consider the physics
> and do a little math. See how much desiccant it's going to take to
> remove even one gallon per day and then figure up the work involved in
> rejuvenating it every day or two. Then, of course, there's the
> energy. It takes more than the heat of vaporization of water to drive
> it from the desiccant so the energy consumption will actually be
> higher than with a high efficiency refrigeration-type dehumidifier.
>
> You really only have two options - refrigeration-based
> dehumidification and ventilation. The second option is only available
> if there is a source of dry air available. If the outside air is as
> humid as indoors then ventilation will do you no good.
>
> It takes a relatively large amount of energy to dehumidify simply
> because water has such a high heat of vaporization. That heat has to
> be absorbed to condense the water vapor into liquid water. That's
> something we're stuck with. The only way to reduce the power
> consumption is to find a more efficient refrigeration unit and/or
> reduce the moisture influx.
>
> You may find as I did that a high SEER window AC is more efficient
> than a typical dehumidifier. I found that an 8000 BTU 11 SEER window
> unit was considerably more efficient than any dehumidifier available
> on the local market AND it removed much more water AND it was a LOT
> cheaper (about $90 vs over $200 for typical dehumidifier). I have it
> sitting on a platform over the floor drain in my basement. I drilled
> a hole in the bottom to let the condensate drain to the floor drain
> and blocked the little tube that normally carries the condensate to
> the condenser to be evaporated outside. I have an external humidistat
> wired to the unit to turn it off in the unlikely event it ever dries
> the basement below 50% RH.
>
> The way to evaluate the efficiency is in terms of water removed per
> unit of energy. That would normally be grams/ounces/gallons of water
> per kilowatt-hour. The nameplate power consumption is, in my
> experience, usually higher than actual. Actually measuring the power
> consumption using a Kill-a-Watt (KAW) or equiv is the way to
> accurately determine efficiency.
>
> When I was choosing my AC unit, I carried my KAW to the various stores
> and actually operated each unit under consideration.
>
> There is one limitation to using an AC and that is the limit of
> humidity reduction. ACs are designed to never bring the evaporator
> below freezing and typically don't go below about 38 degs. That means
> that the humidity can't go below about 40 deg wet bulb which is about
> 38% RH for a dry bulb temperature of 70 degrees. If you need to go
> below that you'll have to get a freezing dehumidifier. This type of
> dehumidifier is designed to freeze the evaporator and periodically
> thaw it. Only go that route if you need the lower humidity, for the
> freezing style is a little less efficient.
>
> The best return on investment will be dollars spent reducing the
> moisture influx. Sealing the concrete floor and walls, for instance,
> can dramatically reduce the moisture that diffuses through them.
>
> As part of my moisture reduction program I had the dirt next to the
> house dug out to below the foundation, coated the blocks with tar and
> black poly, installed a french drain and backfilled a foot or two with
> gravel before replacing the dirt. I also graded the fill away from
> the house to ensure that rain water didn't flow back against the
> walls. I painted the inside walls with that water sealer paint that
> the home improvement stores sell and I coated the floor with cement
> floor paint.
>
> It is far too humid to rely on ventilation where I live so the
> moisture reduction program and the dehumidifier were the techniques
> necessary. My basement went from having billowing growths of mildew
> and other fungus growing on the floor studs to being pretty much as
> dry as the house.
>
> John
>
> On Mon, 24 Jul 2006 18:17:16 +0100, "Nottnick"
> <nmmnews@bellows.org.uk> wrote:
>
> ---
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> Cleveland, Occupied TN
> Don't let your schooling interfere with your education-Mark Twain

Thanks John

Really useful information.

Nick

Nottnick

2006-07-26, 9:25 am

"Mary Fisher" <mary.fisher@zetnet.co.uk> wrote in message
news:44c5fa88$0$910$4c56ba96@master.news.zetnet.net...
>
> "Nottnick" <nmmnews@bellows.org.uk> wrote in message
> news:ka-dncBz17-rFFnZnZ2dnUVZ8tydnZ2d@bt.com...
>
> Where in UK are you, Nick?
>
> Mary

Nottingham
>
>

nicksanspam@ece.villanova.edu

2006-07-26, 9:25 am

"Neon John" <no@never.com> wrote in message

> You may find as I did that a high SEER window AC is more efficient
> than a typical dehumidifier. I found that an 8000 BTU 11 SEER window
> unit was considerably more efficient than any dehumidifier available
> on the local market... The way to evaluate the efficiency is in terms
> of water removed per unit of energy... When I was choosing my AC unit,
> I carried my KAW to the various stores and actually operated each unit
> under consideration.

Fascinating. How did you measure the water removed? Sounds like that would
take a long time, and there might be trapped pockets, and the store air
might be so dry that an AC couldn't remove any water.

Nick

m Ransley

2006-07-26, 9:25 am

To run all the time and not remove near rated water amount it might be
low on freon, also at cooler temps less water is removed and the coil
can freeze. Many dehumidifiers will freeze the coil below 65F, does
yours freeze up. You first need an accurate humidistat, get a digital
unit or analog you can and do calibrate. Did you use an amp meter or
Kill a watt to measure draw and overall power used. I would bet you
could use a new efficient dehumidifier, unless you can get yours checked
and charged cheaply.

Neon John

2006-07-26, 1:25 pm

In the store I couldn't. In the store I simply tested like-rated
units for power consumption and chose the lowest couple to try. I
bought a couple of different ACs and a dehumidifier (as a reference,
later to go in my walk-in gun safe) and took 'em home.

At home I measured the performance the old-fashioned way - the KAW in
the power cord and a graduated beaker to catch the water. Most ACs,
these included, can be tipped a bit to cause the water to run out and
bypass the condenser fan slinger.

The performances of the ACs were so close to each other as to not
matter. I kept the lowest power one and took the other back. Both
were significantly better than the freezing dehumidifier which I
expected.

I like to keep my gun safe at 40% RH, plus or minus a little - low
enough to completely impede rust and yet not dry enough to cause the
wood rifle stocks to crack or distort. The freezing dehumidifier does
that with ease. The window units would bustin' a gut to get that low.

On 26 Jul 2006 07:55:32 -0400, nicksanspam@ece.villanova.edu wrote:

>"Neon John" <no@never.com> wrote in message
>
>
>Fascinating. How did you measure the water removed? Sounds like that would
>take a long time, and there might be trapped pockets, and the store air
>might be so dry that an AC couldn't remove any water.
>
>Nick
---
John De Armond
See my website for my current email address
http://www.neon-john.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain

daestrom

2006-07-26, 5:25 pm

"samc" <remprefix.samuel.7scrubthis9@tiscali.co.uk> wrote in message
news:44c4c039$1_2@mk-nntp-2.news.uk.tiscali.com...
> Nottnick wrote:
> there are 2 main systems for stopping damp/flooding in cellar's .
> (1) a vapour barrour is placed on the walls/floor with a sump in the
> center of the floor for the water to be extracted with a pump .
> (2) the earth is dug away from the sides of the cellar out side and a
> inpervious barryour is appleyd to the out side walls .
> prob not what you wanted to hear I know .

Well....

*sometimes* ventilation is your enemy. Here in the northeast US, basements
are quite a bit cooler than the air temperature. What may pass for 60% RH
during the day may cause high humidity problems in a cool basement/cellar.

Basically, if the dew point outside is anywhere near the temperature of the
air in the basement, no amount of water proofing of the basement walls/floor
will prevent air from cooling as it enters the basement and causing humidity
problems.

One common test for "which is it?" is to tape a piece of clear plastic on
the basement wall, sealing all edges with tape. After a couple of days, if
the space between wall and plastic is wet, then your fix is the way to go
(moisture is seeping through the walls). If it is dry, or only the exposed
surface is damp, then high RH is being caused by ventilation air entering
the basement.

daestrom

Mary Fisher

2006-07-27, 1:25 pm

"Nottnick" <nmmnews@bellows.org.uk> wrote in message
news:rLWdnQ929aXlyVrZnZ2dnUVZ8qWdnZ2d@bt.com...
>

>
> Nottingham

Sorry, Nick, I can't remember why I asked that now - it's been a disrupted
today and yeterday we spent at Flamorough. If I remember I'll ask by mail.
if that's not your address mail me if you like.

Mary
>
>

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