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Window Heater

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  Window Heater rickman <gnuarm@gmail.com> - 2017-02-11 22:02 -0500
    Re: Window Heater bill.sloman@ieee.org - 2017-02-11 20:57 -0800
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 01:02 -0500
        Re: Window Heater whit3rd <whit3rd@gmail.com> - 2017-02-11 23:07 -0800
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 03:52 -0500
            Re: Window Heater whit3rd <whit3rd@gmail.com> - 2017-02-12 18:32 -0800
              Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 21:42 -0500
                Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-13 10:04 -0600
                  Re: Window Heater makolber@yahoo.com - 2017-02-13 10:17 -0800
                  Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-13 15:30 -0500
                    Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-13 15:39 -0600
                      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-13 20:28 -0500
                        Re: Window Heater krw@notreal.com - 2017-02-13 20:48 -0500
                    Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-13 13:47 -0800
              Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 06:56 -0800
                Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-14 07:17 -0800
                  Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 13:20 -0800
                    Re: Window Heater George Herold <gherold@teachspin.com> - 2017-02-14 16:17 -0800
                    Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-14 16:28 -0800
                      Re: Window Heater George Herold <gherold@teachspin.com> - 2017-02-14 17:42 -0800
                        Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 21:18 -0500
                        Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 19:20 -0800
                          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 22:42 -0500
                          Re: Window Heater George Herold <gherold@teachspin.com> - 2017-02-15 06:51 -0800
                        Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-15 06:06 -0800
                          Re: Window Heater George Herold <gherold@teachspin.com> - 2017-02-15 06:54 -0800
                            Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-15 09:15 -0800
                          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-15 15:02 -0500
                            Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-15 16:38 -0800
                              Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-15 19:50 -0500
                          Re: Window Heater Martin Brown <|||newspam|||@nezumi.demon.co.uk> - 2017-02-17 11:18 +0000
                      Re: Window Heater Martin Brown <|||newspam|||@nezumi.demon.co.uk> - 2017-02-16 08:28 +0000
                Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 14:07 -0500
                  Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 12:57 -0800
                    Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 17:32 -0500
                      Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 19:12 -0800
                Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 14:16 -0500
                  Re: Window Heater dagmargoodboat@yahoo.com - 2017-02-14 12:53 -0800
                    Re: Window Heater John S <Sophi.2@invalid.org> - 2017-02-14 16:14 -0600
                      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 17:35 -0500
                        Re: Window Heater John S <Sophi.2@invalid.org> - 2017-02-15 10:45 -0600
                          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-15 15:06 -0500
                            Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-15 16:46 -0500
                    Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 17:34 -0500
        Re: Window Heater bill.sloman@ieee.org - 2017-02-12 04:57 -0800
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 18:19 -0500
        Re: Window Heater Winfield Hill <hill@rowland.harvard.edu> - 2017-02-12 10:42 -0800
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 18:30 -0500
      Re: Window Heater Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-12 08:45 +0000
        Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 03:57 -0500
          Re: Window Heater Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-12 09:34 +0000
    Re: Window Heater Jon Elson <elson@pico-systems.com> - 2017-02-11 23:52 -0600
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 01:07 -0500
        Re: Window Heater Martin Brown <|||newspam|||@nezumi.demon.co.uk> - 2017-02-14 10:40 +0000
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 06:00 -0500
            Re: Window Heater John S <Sophi.2@invalid.org> - 2017-02-14 16:17 -0600
              Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-14 14:28 -0800
              Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-14 17:36 -0500
    Re: Window Heater Mikko OH2HVJ <mikko.syrjalahti@nospam.fi> - 2017-02-12 14:54 +0200
      Re: Window Heater Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-12 08:56 -0700
        Re: Window Heater Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-02-12 20:14 +0200
          Re: Window Heater Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-11 00:30 -0500
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 18:56 -0500
    Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-12 06:35 -0800
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 19:01 -0500
        Re: Window Heater "dcaster@krl.org" <dcaster@krl.org> - 2017-02-12 17:29 -0800
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 21:37 -0500
            Re: Window Heater Jon Elson <jmelson@wustl.edu> - 2017-02-13 15:08 -0600
              Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-13 13:32 -0800
    Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-12 08:20 -0800
    Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-12 11:48 -0600
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 19:03 -0500
        Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-13 09:58 -0600
          Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-13 15:33 -0500
            Re: Window Heater Jon Elson <jmelson@wustl.edu> - 2017-02-13 15:10 -0600
              Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-13 13:36 -0800
              Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-13 15:40 -0600
              Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-13 20:34 -0500
            Re: Window Heater krw@notreal.com - 2017-02-13 20:52 -0500
    Re: Window Heater Tim Wescott <seemywebsite@myfooter.really> - 2017-02-12 12:02 -0600
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 19:05 -0500
        Re: Window Heater Tim Wescott <seemywebsite@myfooter.really> - 2017-02-14 17:49 -0600
    Re: Window Heater bitrex <bitrex@de.lete.earthlink.net> - 2017-02-12 13:06 -0500
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-12 19:05 -0500
    Re: Window Heater Clifford Heath <no.spam@please.net> - 2017-02-13 11:21 +1100
    Re: Window Heater krw@notreal.com - 2017-02-12 19:28 -0500
    Re: Window Heater Martin Riddle <martin_ridd@verizon.net> - 2017-02-12 21:57 -0500
      Re: Window Heater "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-13 10:01 -0600
    Re: Window Heater Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-13 13:49 -0800
      Re: Window Heater rickman <gnuarm@gmail.com> - 2017-02-13 20:36 -0500
    Re: Window Heater rickman <gnuarm@gmail.com> - 2017-03-01 19:44 -0500
      Re: Window Heater George Herold <gherold@teachspin.com> - 2017-03-01 17:33 -0800

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#447363 — Window Heater

I sit directly under a window much of the time (don't suggest I move, 
there just isn't another practical option).  When it is cold the window 
has a draft that is downright brutal.  I plugged the window with a 3/4 
inch piece of Styrofoam insulation and the draft persists (sealed with 
tape around the edges).  Seems even a couple of degrees difference with 
the room air can create a draft that is cold enough to be a bother. The 
wall around the window reads 66 degrees while the Styrofoam reads about 
64 degrees.

I thought maybe the way to deal with the draft is to fight cold with 
fire.  So I bought a few power resistors in the metal cases that can be 
mounted.  I wired them in series and connected a variable supply as I 
didn't know how much power I would need.  Turns out a fair amount.  If I 
crank up the heat to around 30 to 40 watts with the resistors right 
behind me on the sill of the window, the draft is gone.  Not bad.

But I was wondering how best to mount them.  At this wattage they get 
pretty warm, around 200 degrees!  I was looking at sheet aluminum to 
mount them to thinking just a couple/three inches of height would do the 
job.  But now I am wondering.  I'm not sure a string of resistors along 
a three inch wide sheet of aluminum would reduce the temps that much and 
I'm not at all clear on how that might affect the airflow.

I am thinking of a much wider sheet that would not get so hot.  I am 
also thinking it would help better to cut the draft by being larger. 
I'm thinking it would give rise to a reverse draft and possibly require 
less heat.

So which is better, a small hotter heat source or a spread out lower 
heat source.  I suppose covering the entire windows with aluminum would 
be the best approach, but I'm not ready to do that.  So maybe 12 inches 
of aluminum sheet?

-- 

Rick C

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#447373

On Sunday, February 12, 2017 at 2:02:37 PM UTC+11, rickman wrote:
> I sit directly under a window much of the time (don't suggest I move, 
> there just isn't another practical option).  When it is cold the window 
> has a draft that is downright brutal.  I plugged the window with a 3/4 
> inch piece of Styrofoam insulation and the draft persists (sealed with 
> tape around the edges).  Seems even a couple of degrees difference with 
> the room air can create a draft that is cold enough to be a bother. The 
> wall around the window reads 66 degrees while the Styrofoam reads about 
> 64 degrees.
> 
> I thought maybe the way to deal with the draft is to fight cold with 
> fire.  So I bought a few power resistors in the metal cases that can be 
> mounted.  I wired them in series and connected a variable supply as I 
> didn't know how much power I would need.  Turns out a fair amount.  If I 
> crank up the heat to around 30 to 40 watts with the resistors right 
> behind me on the sill of the window, the draft is gone.  Not bad.
> 
> But I was wondering how best to mount them.  At this wattage they get 
> pretty warm, around 200 degrees!  I was looking at sheet aluminum to 
> mount them to thinking just a couple/three inches of height would do the 
> job.  But now I am wondering.  I'm not sure a string of resistors along 
> a three inch wide sheet of aluminum would reduce the temps that much and 
> I'm not at all clear on how that might affect the airflow.
> 
> I am thinking of a much wider sheet that would not get so hot.  I am 
> also thinking it would help better to cut the draft by being larger. 
> I'm thinking it would give rise to a reverse draft and possibly require 
> less heat.
> 
> So which is better, a small hotter heat source or a spread out lower 
> heat source.  I suppose covering the entire windows with aluminum would 
> be the best approach, but I'm not ready to do that.  So maybe 12 inches 
> of aluminum sheet?

A more sensible approach would be to replace the single layer of glass in the window with double-glazing. You can use a second sheet of polycarbonate space off from the glass by about 10mm to dramatically reduce heat losses.

In the UK this was called secondary double glazing and you could buy a kit of parts at do-it-yourself shops. Typically it went onto the window frame, rather than onto the glass itself.

If the window is deep enough, you can just measure the dimensions of the window, order a suitable double-glazed pane from your neighbourhood glazier, and replace the existing single pane of glass with the double-glazed assembly.

I've done both. The replacement pane is neater. Don't forget that window glass isn't a tight fit inside the window frame - you need a 6mm (0.25 inch) gap between the glass and the frame which is filled by putty or non-setting glazing compound - to take up differential expansion.

Triple glazing is even better. Apparently the Swedish love it. The panes get a bit deep.

-- 
Bill Sloman, Sydney

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#447381

On 2/11/2017 11:57 PM, bill.sloman@ieee.org wrote:
> On Sunday, February 12, 2017 at 2:02:37 PM UTC+11, rickman wrote:
>> I sit directly under a window much of the time (don't suggest I
>> move, there just isn't another practical option).  When it is cold
>> the window has a draft that is downright brutal.  I plugged the
>> window with a 3/4 inch piece of Styrofoam insulation and the draft
>> persists (sealed with tape around the edges).  Seems even a couple
>> of degrees difference with the room air can create a draft that is
>> cold enough to be a bother. The wall around the window reads 66
>> degrees while the Styrofoam reads about 64 degrees.
>>
>> I thought maybe the way to deal with the draft is to fight cold
>> with fire.  So I bought a few power resistors in the metal cases
>> that can be mounted.  I wired them in series and connected a
>> variable supply as I didn't know how much power I would need.
>> Turns out a fair amount.  If I crank up the heat to around 30 to 40
>> watts with the resistors right behind me on the sill of the window,
>> the draft is gone.  Not bad.
>>
>> But I was wondering how best to mount them.  At this wattage they
>> get pretty warm, around 200 degrees!  I was looking at sheet
>> aluminum to mount them to thinking just a couple/three inches of
>> height would do the job.  But now I am wondering.  I'm not sure a
>> string of resistors along a three inch wide sheet of aluminum would
>> reduce the temps that much and I'm not at all clear on how that
>> might affect the airflow.
>>
>> I am thinking of a much wider sheet that would not get so hot.  I
>> am also thinking it would help better to cut the draft by being
>> larger. I'm thinking it would give rise to a reverse draft and
>> possibly require less heat.
>>
>> So which is better, a small hotter heat source or a spread out
>> lower heat source.  I suppose covering the entire windows with
>> aluminum would be the best approach, but I'm not ready to do that.
>> So maybe 12 inches of aluminum sheet?
>
> A more sensible approach would be to replace the single layer of
> glass in the window with double-glazing. You can use a second sheet
> of polycarbonate space off from the glass by about 10mm to
> dramatically reduce heat losses.

What part of my post made you think the glass was single pane???


> In the UK this was called secondary double glazing and you could buy
> a kit of parts at do-it-yourself shops. Typically it went onto the
> window frame, rather than onto the glass itself.
>
> If the window is deep enough, you can just measure the dimensions of
> the window, order a suitable double-glazed pane from your
> neighbourhood glazier, and replace the existing single pane of glass
> with the double-glazed assembly.
>
> I've done both. The replacement pane is neater. Don't forget that
> window glass isn't a tight fit inside the window frame - you need a
> 6mm (0.25 inch) gap between the glass and the frame which is filled
> by putty or non-setting glazing compound - to take up differential
> expansion.
>
> Triple glazing is even better. Apparently the Swedish love it. The
> panes get a bit deep.

I tried it.  The window is already double glazed and I added a layer of 
plastic sheet (they sell kits for this).  It helped, but no more (likely 
less) than the 3/4 inch Styrofoam.  I don't recall if I've tried both.

My original idea with the heater was to add the plastic with the heater 
in the space between the plastic and the Styrofoam.  I expected that to 
use very little extra heat.  But I don't like the plastic sheet and 
wanted to try this.

Now that I think of that, heating the space behind the plastic reminds 
me of your ultra fine temperature controller.  You put the sensor and 
the heater at the thin spot in the insulation.  Heating the space in the 
window would completely stop the draft.

The surprising part of the whole thing is just how small a temperature 
difference will result in a draft.  I only measure 2 or 3 degrees 
difference between the Styrofoam and other objects in the room, yet the 
draft forms when it is very cold out.  Likely the walls also create a 
draft, but not as pronounced.  Sitting with my back to the window 
doesn't help, but like I said, no practical way to deal with that.

-- 

Rick C

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#447384

On Saturday, February 11, 2017 at 10:02:38 PM UTC-8, rickman wrote:
> On 2/11/2017 11:57 PM, bill.sloman@ieee.org wrote:
> > On Sunday, February 12, 2017 at 2:02:37 PM UTC+11, rickman wrote:
> >> I sit directly under a window much of the time (don't suggest I
> >> move, there just isn't another practical option).  When it is cold
> >> the window has a draft that is downright brutal. 

> > Triple glazing is even better. Apparently the Swedish love it. The
> > panes get a bit deep.
> 
> I tried it.  The window is already double glazed and I added a layer of 
> plastic sheet (they sell kits for this).  It helped, but... 

Have you considered that, rather than a draft, your chill is due to
radiated heat loss?  There's low-E options on double glazing, that are
intended to take care of that.   It costs a few extra dollars when your
glass shop takes the order, though.

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#447390

On 2/12/2017 2:07 AM, whit3rd wrote:
> On Saturday, February 11, 2017 at 10:02:38 PM UTC-8, rickman wrote:
>> On 2/11/2017 11:57 PM, bill.sloman@ieee.org wrote:
>>> On Sunday, February 12, 2017 at 2:02:37 PM UTC+11, rickman wrote:
>>>> I sit directly under a window much of the time (don't suggest I
>>>> move, there just isn't another practical option).  When it is cold
>>>> the window has a draft that is downright brutal.
>
>>> Triple glazing is even better. Apparently the Swedish love it. The
>>> panes get a bit deep.
>>
>> I tried it.  The window is already double glazed and I added a layer of
>> plastic sheet (they sell kits for this).  It helped, but...
>
> Have you considered that, rather than a draft, your chill is due to
> radiated heat loss?  There's low-E options on double glazing, that are
> intended to take care of that.   It costs a few extra dollars when your
> glass shop takes the order, though.

Radiated heat loss through 3/4 inch of Styrofoam???  Really?

-- 

Rick C

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#447511

On Sunday, February 12, 2017 at 12:52:10 AM UTC-8, rickman wrote:
> On 2/12/2017 2:07 AM, whit3rd wrote:
> > On Saturday, February 11, 2017 at 10:02:38 PM UTC-8, rickman wrote:

> > Have you considered that, rather than a draft, your chill is due to
> > radiated heat loss? 

> Radiated heat loss through 3/4 inch of Styrofoam???  Really?

Sure.  Long-wavelength IR; things that look cloudy white at visible wavelengths
are transparent to longer wavelengths.   You can't see UV light, because
the human eye lens is a cloudy white in that part of the spectrum.
Good insulation has to be opaque.   

Unless, the styrofoam is the foil-backed kind?

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#447513

On 2/12/2017 9:32 PM, whit3rd wrote:
> On Sunday, February 12, 2017 at 12:52:10 AM UTC-8, rickman wrote:
>> On 2/12/2017 2:07 AM, whit3rd wrote:
>>> On Saturday, February 11, 2017 at 10:02:38 PM UTC-8, rickman wrote:
>
>>> Have you considered that, rather than a draft, your chill is due to
>>> radiated heat loss?
>
>> Radiated heat loss through 3/4 inch of Styrofoam???  Really?
>
> Sure.  Long-wavelength IR; things that look cloudy white at visible wavelengths
> are transparent to longer wavelengths.   You can't see UV light, because
> the human eye lens is a cloudy white in that part of the spectrum.
> Good insulation has to be opaque.
>
> Unless, the styrofoam is the foil-backed kind?

No, it's the ugly green type.   I don't think I could stand to look at 
foil from either side.  In fact, at some point I am going to put up 
something that will cover the Styrofoam.  It's not only green, but 
covered with writing.  I may be a geek, but that's pretty ugly, even to me!

I also miss the light.  Sitting in a room without daylight is not so 
fun.  I have a work table in the living room with a great view, but that 
whole room is just too cold.  Lots of glass and even skylights.  I use 
that in the warmer months.

-- 

Rick C

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#447562

"rickman" <gnuarm@gmail.com> wrote in message 
news:o7r6ao$19v$1@dont-email.me...
>> Unless, the styrofoam is the foil-backed kind?
>
> No, it's the ugly green type.

FYI, "Styrofoam" is a brand name of a particular chemical composition 
(polystyrene, of course).  The colored stuff is one of several kinds of 
isocyanate (polyurethane).

Tim

-- 
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: http://seventransistorlabs.com 

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#447571

75W incandescent reflector type spot light aimed at your back will keep you toasty


 m

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#447588

On 2/13/2017 11:04 AM, Tim Williams wrote:
> "rickman" <gnuarm@gmail.com> wrote in message
> news:o7r6ao$19v$1@dont-email.me...
>>> Unless, the styrofoam is the foil-backed kind?
>>
>> No, it's the ugly green type.
>
> FYI, "Styrofoam" is a brand name of a particular chemical composition
> (polystyrene, of course).  The colored stuff is one of several kinds of
> isocyanate (polyurethane).

Nope, it says "extruded polystyrene" right on it.

https://mobileimages.lowes.com/product/converted/071215/071215480758.jpg

It's called Styrofoam the way office copiers are called Xerox machines. 
No one says "extruded polystyrene".

-- 

Rick C

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#447594

"rickman" <gnuarm@gmail.com> wrote in message 
news:o7t4ul$b4l$1@dont-email.me...
> Nope, it says "extruded polystyrene" right on it.
>
> https://mobileimages.lowes.com/product/converted/071215/071215480758.jpg
>

Hmm, nevermind, guess they do!

(Wonder if it's the pink stuff that's usually isocyanate, then?)


> It's called Styrofoam the way office copiers are called Xerox machines. No 
> one says "extruded polystyrene".

No, that would get them in trouble pretty quickly.  Dow is still around, 
and... bigger than Xerox probably?

Unless you meant what you said earlier, in which case, no, they're probably 
not too happy about that, but genericized it is!

Tim

-- 
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: http://seventransistorlabs.com 

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#447606

On 2/13/2017 4:39 PM, Tim Williams wrote:
> "rickman" <gnuarm@gmail.com> wrote in message
> news:o7t4ul$b4l$1@dont-email.me...
>> Nope, it says "extruded polystyrene" right on it.
>>
>> https://mobileimages.lowes.com/product/converted/071215/071215480758.jpg
>>
>
> Hmm, nevermind, guess they do!
>
> (Wonder if it's the pink stuff that's usually isocyanate, then?)
>
>
>> It's called Styrofoam the way office copiers are called Xerox
>> machines. No one says "extruded polystyrene".
>
> No, that would get them in trouble pretty quickly.  Dow is still around,
> and... bigger than Xerox probably?
>
> Unless you meant what you said earlier, in which case, no, they're
> probably not too happy about that, but genericized it is!

I recall Xerox was not happy with the use of their name in the generic 
for copiers.  They attempted an ad campaign, but there was nothing they 
could do.  That said, you can't put Styrofoam on your "extruded 
polystyrene" products unless you are Dow... lol

Wow!  I just read wikipedia on this (and some other references) and it 
seems there is a lot more to it.  First, Styrofoam is "extruded 
polystyrene" while styrofoam is not.  The stuff we generically refer to 
as styrofoam is actually "expanded polystyrene" which is slightly 
different.

I was in a styrofoam factory once working on the alarm system.  They 
used small pellets of polystyrene soaked in pentane which were placed in 
a rectangular mold.  On heating the polystyrene softens and the pentane 
turns to a gas expanding the beads.  If there are enough to more than 
fill the mold after expanding they stick together making the stuff we 
put food in.  Extruded polystyrene is not made from the beads, but is 
made of the same stuff that is in the beads.  Dow only sells it for 
thermal insulation and is dyed a light blue as a trademark.  Corning 
dyes their similar product pink and they've trademarked that color!  So 
the color indicates brand rather than material.

-- 

Rick C

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#447611

On Mon, 13 Feb 2017 20:28:46 -0500, rickman <gnuarm@gmail.com> wrote:

>On 2/13/2017 4:39 PM, Tim Williams wrote:
>> "rickman" <gnuarm@gmail.com> wrote in message
>> news:o7t4ul$b4l$1@dont-email.me...
>>> Nope, it says "extruded polystyrene" right on it.
>>>
>>> https://mobileimages.lowes.com/product/converted/071215/071215480758.jpg
>>>
>>
>> Hmm, nevermind, guess they do!
>>
>> (Wonder if it's the pink stuff that's usually isocyanate, then?)
>>
>>
>>> It's called Styrofoam the way office copiers are called Xerox
>>> machines. No one says "extruded polystyrene".
>>
>> No, that would get them in trouble pretty quickly.  Dow is still around,
>> and... bigger than Xerox probably?
>>
>> Unless you meant what you said earlier, in which case, no, they're
>> probably not too happy about that, but genericized it is!
>
>I recall Xerox was not happy with the use of their name in the generic 
>for copiers.  They attempted an ad campaign, but there was nothing they 
>could do.  That said, you can't put Styrofoam on your "extruded 
>polystyrene" products unless you are Dow... lol

Kleenex, asperin, and many other brands have made their way into the
language.  The original companies have lost their trademark.

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#447596

Den mandag den 13. februar 2017 kl. 21.31.06 UTC+1 skrev rickman:
> On 2/13/2017 11:04 AM, Tim Williams wrote:
> > "rickman" <gnuarm@gmail.com> wrote in message
> > news:o7r6ao$19v$1@dont-email.me...
> >>> Unless, the styrofoam is the foil-backed kind?
> >>
> >> No, it's the ugly green type.
> >
> > FYI, "Styrofoam" is a brand name of a particular chemical composition
> > (polystyrene, of course).  The colored stuff is one of several kinds of
> > isocyanate (polyurethane).
> 
> Nope, it says "extruded polystyrene" right on it.
> 
> https://mobileimages.lowes.com/product/converted/071215/071215480758.jpg
> 
> It's called Styrofoam the way office copiers are called Xerox machines. 
> No one says "extruded polystyrene".

here it is called "Flamingo" because that is what the company that first sold
it here called it 

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#447642

On Sunday, February 12, 2017 at 9:32:52 PM UTC-5, whit3rd wrote:
> On Sunday, February 12, 2017 at 12:52:10 AM UTC-8, rickman wrote:
> > On 2/12/2017 2:07 AM, whit3rd wrote:
> > > On Saturday, February 11, 2017 at 10:02:38 PM UTC-8, rickman wrote:
> 
> > > Have you considered that, rather than a draft, your chill is due to
> > > radiated heat loss? 
> 
> > Radiated heat loss through 3/4 inch of Styrofoam???  Really?
> 
> Sure.  Long-wavelength IR; things that look cloudy white at visible wavelengths
> are transparent to longer wavelengths.   You can't see UV light, because
> the human eye lens is a cloudy white in that part of the spectrum.
> Good insulation has to be opaque.   
> 
> Unless, the styrofoam is the foil-backed kind?

You're on the right track (as is krw).

A couple years ago I investigated improving the efficiency of a
refrigerator by adding external insulation.  Measuring the temperature
differential across the insulation allowed measurement and calculation
of the actual loss.

It took 4" of rigid foam insulation[1] to produce the same temperature
differential as was achieved with 1/2" of foil-backed polyisocyanurate
foam.[2]

[1]http://www.homedepot.com/p/Owens-Corning-FOAMULAR-250-2-in-x-48-in-x-8-ft-R-10-Scored-Squared-Edge-Insulation-Sheathing-52DD/202085962

[2]http://www.homedepot.com/p/R-Matte-Rmax-Plus-3-1-2-in-x-4-ft-x-8-ft-R-3-2-Polyisocyanurate-Rigid-Foam-Insulation-Board-754404/100572981

So, the foil barrier is stunningly useful.  (The foil has to be installed
facing the heat source. Anything contacting the foil eliminates the benefit,
since heat is then simply conducted straight through.)

I applied this insight to the exact drafty window problem Rick's solving.
Two aluminized car dashboard shades, held in place at night with tension
rods[3] works amazingly well.

[3]https://www.walmart.com/ip/Mainstays-Spring-Tension-Rod-White/50015124

It was a cheap experiment.

The soft dashboard shades were $1 each at the local DollarTree.  They're not
fully opaque--enough daylight shines through to yield useful illumination,
should you choose to leave them up on a super-cold day.

There's still a draft, but markedly less.  Rick will still probably prefer
his heater.  200w for one heater, though, is as almost much as my whole house
(280w, average draw last month).

Cheers,
James Arthur

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#447644

On Tuesday, February 14, 2017 at 9:56:40 AM UTC-5, dagmarg...@yahoo.com wrote:




> So, the foil barrier is stunningly useful.  (The foil has to be installed
> facing the heat source. Anything contacting the foil eliminates the benefit,
> since heat is then simply conducted straight through.)
> 
> Cheers,
> James Arthur

Foil is very effective for heat flow down.  It stops the radiated heat transfer.
But it is almost useless for heat flow up.  In that case the heat is conducted by convection and the heat transfer by radiation is negligible. For heat flow horizontal it is some what effective.

Polyurethane is usually expanded using CO2.  And CO2 is a heavy gas that does not conduct heat well.  Argon is similar.  So polyurethane foam is a much better insulation than polystyrene foam.  At least for some years.  Eventually water vapor gets into the polyurethane foam.

                                            Dan

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#447661

On Tuesday, February 14, 2017 at 10:17:38 AM UTC-5, dca...@krl.org wrote:
> On Tuesday, February 14, 2017 at 9:56:40 AM UTC-5, dagmarg...@yahoo.com wrote:
> 
> > So, the foil barrier is stunningly useful.  (The foil has to be installed
> > facing the heat source. Anything contacting the foil eliminates the benefit,
> > since heat is then simply conducted straight through.)
> > 
> > Cheers,
> > James Arthur
> 
> Foil is very effective for heat flow down.  It stops the radiated heat transfer.
> But it is almost useless for heat flow up.  In that case the heat is conducted by convection and the heat transfer by radiation is negligible. For heat flow horizontal it is some what effective.

I'm not sure what you mean here by 'up' and 'down'--in this context of a
refrigerator and a window, the surfaces are both vertical and the heat
flow is horizontal, through the insulation.

Vertical surfaces produce convection, but the effects of that are included
in my temperature differential measurements across the outboard 'fridge
insulation. No attempt was made to block convection.

For the windows I should've noted that I've got either blinds or drapes
covering the inside surface to discourage convection, with air gaps between
blinds / car shade / window.

         = s w
(inside) = s w (outside)
         = s w

blinds: '='   shade: 's'   window: 'w'

> Polyurethane is usually expanded using CO2.  And CO2 is a heavy gas that does not conduct heat well.  Argon is similar.  So polyurethane foam is a much better insulation than polystyrene foam.  At least for some years.  Eventually water vapor gets into the polyurethane foam.

I was surprised to realize / learn that the insulating value of a material
is nearly completely inversely dependent on its density--the insulation
value comes not from the material, but from the air gaps.  The materials'
thermal conductivities are nearly always so much higher than their trapped
air that the 'insulating' material used almost doesn't matter.

Cheers,
James Arthur

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#447679

On Tuesday, February 14, 2017 at 4:20:49 PM UTC-5, dagmarg...@yahoo.com wrote:
> On Tuesday, February 14, 2017 at 10:17:38 AM UTC-5, dca...@krl.org wrote:
> > On Tuesday, February 14, 2017 at 9:56:40 AM UTC-5, dagmarg...@yahoo.com wrote:
> > 
> > > So, the foil barrier is stunningly useful.  (The foil has to be installed
> > > facing the heat source. Anything contacting the foil eliminates the benefit,
> > > since heat is then simply conducted straight through.)
> > > 
> > > Cheers,
> > > James Arthur
> > 
> > Foil is very effective for heat flow down.  It stops the radiated heat transfer.
> > But it is almost useless for heat flow up.  In that case the heat is conducted by convection and the heat transfer by radiation is negligible. For heat flow horizontal it is some what effective.
> 
> I'm not sure what you mean here by 'up' and 'down'--in this context of a
> refrigerator and a window, the surfaces are both vertical and the heat
> flow is horizontal, through the insulation.
> 
> Vertical surfaces produce convection, but the effects of that are included
> in my temperature differential measurements across the outboard 'fridge
> insulation. No attempt was made to block convection.
> 
> For the windows I should've noted that I've got either blinds or drapes
> covering the inside surface to discourage convection, with air gaps between
> blinds / car shade / window.
> 
>          = s w
> (inside) = s w (outside)
>          = s w
> 
> blinds: '='   shade: 's'   window: 'w'
> 
> > Polyurethane is usually expanded using CO2.  And CO2 is a heavy gas that does not conduct heat well.  Argon is similar.  So polyurethane foam is a much better insulation than polystyrene foam.  At least for some years.  Eventually water vapor gets into the polyurethane foam.
> 
> I was surprised to realize / learn that the insulating value of a material
> is nearly completely inversely dependent on its density--the insulation
> value comes not from the material, but from the air gaps.  The materials'
> thermal conductivities are nearly always so much higher than their trapped
> air that the 'insulating' material used almost doesn't matter.
> 
> Cheers,
> James Arthur

Some summer day, I couldn't find my beer cozy (foam cylinder) 
and so wrapped my can of beer in a piece of aluminized mylar
(space/saftey  blanket) many layers. 
Worked great, (it was a bit fussy around the lips.)
If you put it in a can and pump vacuum around it. 
it's called super insulation.  (I figure you probably know this)
I've always wondered how good it is w/o vacuum, 
just in air.  (guess I'll have to measure some day...)

George H. 

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#447680

On Tuesday, February 14, 2017 at 4:20:49 PM UTC-5, dagmarg...@yahoo.com wrote:


> 
> I'm not sure what you mean here by 'up' and 'down'--in this context of a
> refrigerator and a window, the surfaces are both vertical and the heat
> flow is horizontal, through the insulation

I was commenting on heat flow in general.  Not just about the window case.
So if you are insulating an attic, in summer the heat flow is down and in the winter  the heat flow is up.  So in the summer the foil will help a lot and in the winter foil will have almost no effect.

                                   Dan


> Vertical surfaces produce convection, but the effects of that are included
> in my temperature differential measurements across the outboard 'fridge
> insulation. No attempt was made to block convection.
> 
> For the windows I should've noted that I've got either blinds or drapes
> covering the inside surface to discourage convection, with air gaps between
> blinds / car shade / window.
> 
>          = s w
> (inside) = s w (outside)
>          = s w
> 
> blinds: '='   shade: 's'   window: 'w'
> 
> > Polyurethane is usually expanded using CO2.  And CO2 is a heavy gas that does not conduct heat well.  Argon is similar.  So polyurethane foam is a much better insulation than polystyrene foam.  At least for some years.  Eventually water vapor gets into the polyurethane foam.
> 
> I was surprised to realize / learn that the insulating value of a material
> is nearly completely inversely dependent on its density--the insulation
> value comes not from the material, but from the air gaps.  The materials'
> thermal conductivities are nearly always so much higher than their trapped
> air that the 'insulating' material used almost doesn't matter.
> 
> Cheers,
> James Arthur

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#447688

On Tuesday, February 14, 2017 at 7:28:58 PM UTC-5, dca...@krl.org wrote:
> On Tuesday, February 14, 2017 at 4:20:49 PM UTC-5, dagmarg...@yahoo.com wrote:
> 
> 
> > 
> > I'm not sure what you mean here by 'up' and 'down'--in this context of a
> > refrigerator and a window, the surfaces are both vertical and the heat
> > flow is horizontal, through the insulation
> 
> I was commenting on heat flow in general.  Not just about the window case.
> So if you are insulating an attic, in summer the heat flow is down and in the winter  the heat flow is up.  So in the summer the foil will help a lot and in the winter foil will have almost no effect.

OK, I'm not sure in practice, but in theory I don'think it 
should matter much which side of the foil is hot or cold.  
It's an IR reflector, pretty much the same from both sides..
(What's the peak wavelength/ frequency at ~300K)

George H. 
> 
>                                    Dan
> 
> 
> > Vertical surfaces produce convection, but the effects of that are included
> > in my temperature differential measurements across the outboard 'fridge
> > insulation. No attempt was made to block convection.
> > 
> > For the windows I should've noted that I've got either blinds or drapes
> > covering the inside surface to discourage convection, with air gaps between
> > blinds / car shade / window.
> > 
> >          = s w
> > (inside) = s w (outside)
> >          = s w
> > 
> > blinds: '='   shade: 's'   window: 'w'
> > 
> > > Polyurethane is usually expanded using CO2.  And CO2 is a heavy gas that does not conduct heat well.  Argon is similar.  So polyurethane foam is a much better insulation than polystyrene foam.  At least for some years.  Eventually water vapor gets into the polyurethane foam.
> > 
> > I was surprised to realize / learn that the insulating value of a material
> > is nearly completely inversely dependent on its density--the insulation
> > value comes not from the material, but from the air gaps.  The materials'
> > thermal conductivities are nearly always so much higher than their trapped
> > air that the 'insulating' material used almost doesn't matter.
> > 
> > Cheers,
> > James Arthur

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