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Groups > sci.electronics.design > #447363 > unrolled thread
| Started by | rickman <gnuarm@gmail.com> |
|---|---|
| First post | 2017-02-11 22:02 -0500 |
| Last post | 2017-03-01 17:33 -0800 |
| Articles | 20 on this page of 92 — 24 participants |
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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
Page 3 of 5 — ← Prev page 1 2 [3] 4 5 Next page →
| From | John S <Sophi.2@invalid.org> |
|---|---|
| Date | 2017-02-15 10:45 -0600 |
| Message-ID | <o820et$mc9$1@dont-email.me> |
| In reply to | #447670 |
On 2/14/2017 4:35 PM, rickman wrote: > On 2/14/2017 5:14 PM, John S wrote: >> On 2/14/2017 2:53 PM, dagmargoodboat@yahoo.com wrote: >>> On Tuesday, February 14, 2017 at 2:16:49 PM UTC-5, rickman wrote: >>>> On 2/14/2017 9:56 AM, dagmargoodboat@yahoo.com wrote: >>>>> 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). >>>> >>>> Your number for electricity usage is a bit low. My usage last bill was >>>> 2350 kW average. 1692 kWhr / 720 hr = 2.35 kW costing under $200. Was >>>> your bill in the $20 range? If not I suspect you missed a decimal >>>> point. >>> >>> Why do you seem never to believe other people? I used 207 kWhr, >>> and yes, paid about $20 plus $10 service charge. >> >> He doesn't know. His numbers and arithmetic are inconsistent. You should >> not be surprised that he does not believe you. > > What is inconsistent in my numbers or math? > You say 2350kW (kW*hr assumed) billed but you used 1692kW*hr for your calculation. And what purpose does the 2.35kW calculation serve?
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-15 15:06 -0500 |
| Message-ID | <o82c8f$p3g$2@dont-email.me> |
| In reply to | #447748 |
On 2/15/2017 11:45 AM, John S wrote: > On 2/14/2017 4:35 PM, rickman wrote: >> On 2/14/2017 5:14 PM, John S wrote: >>> On 2/14/2017 2:53 PM, dagmargoodboat@yahoo.com wrote: >>>> On Tuesday, February 14, 2017 at 2:16:49 PM UTC-5, rickman wrote: >>>>> On 2/14/2017 9:56 AM, dagmargoodboat@yahoo.com wrote: >>>>>> 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). >>>>> >>>>> Your number for electricity usage is a bit low. My usage last bill >>>>> was >>>>> 2350 kW average. 1692 kWhr / 720 hr = 2.35 kW costing under $200. >>>>> Was >>>>> your bill in the $20 range? If not I suspect you missed a decimal >>>>> point. >>>> >>>> Why do you seem never to believe other people? I used 207 kWhr, >>>> and yes, paid about $20 plus $10 service charge. >>> >>> He doesn't know. His numbers and arithmetic are inconsistent. You should >>> not be surprised that he does not believe you. >> >> What is inconsistent in my numbers or math? >> > > You say 2350kW (kW*hr assumed) billed but you used 1692kW*hr for your > calculation. And what purpose does the 2.35kW calculation serve? And what happens when you ass-ume? I wrote 2350 kW average because that is what I meant. The average usage over that month was 2350 kW. The same number I wrote in the next sentence, "2.35 kW". The surprise to me is that James Arthur is able to live in a way that he only heats a few cubic feet surrounding his body. I don't have a way to do that, but my window heater helps. To otherwise get the same warmth I would need to turn the heat up at least two degrees. -- Rick C
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-15 16:46 -0500 |
| Message-ID | <o82i58$fbt$1@dont-email.me> |
| In reply to | #447780 |
On 2/15/2017 3:06 PM, rickman wrote: > On 2/15/2017 11:45 AM, John S wrote: >> On 2/14/2017 4:35 PM, rickman wrote: >>> On 2/14/2017 5:14 PM, John S wrote: >>>> On 2/14/2017 2:53 PM, dagmargoodboat@yahoo.com wrote: >>>>> On Tuesday, February 14, 2017 at 2:16:49 PM UTC-5, rickman wrote: >>>>>> On 2/14/2017 9:56 AM, dagmargoodboat@yahoo.com wrote: >>>>>>> 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). >>>>>> >>>>>> Your number for electricity usage is a bit low. My usage last bill >>>>>> was >>>>>> 2350 kW average. 1692 kWhr / 720 hr = 2.35 kW costing under $200. >>>>>> Was >>>>>> your bill in the $20 range? If not I suspect you missed a decimal >>>>>> point. >>>>> >>>>> Why do you seem never to believe other people? I used 207 kWhr, >>>>> and yes, paid about $20 plus $10 service charge. >>>> >>>> He doesn't know. His numbers and arithmetic are inconsistent. You >>>> should >>>> not be surprised that he does not believe you. >>> >>> What is inconsistent in my numbers or math? >>> >> >> You say 2350kW (kW*hr assumed) billed but you used 1692kW*hr for your >> calculation. And what purpose does the 2.35kW calculation serve? > > And what happens when you ass-ume? I wrote 2350 kW average because that > is what I meant. The average usage over that month was 2350 kW. The > same number I wrote in the next sentence, "2.35 kW". > > The surprise to me is that James Arthur is able to live in a way that he > only heats a few cubic feet surrounding his body. I don't have a way to > do that, but my window heater helps. To otherwise get the same warmth I > would need to turn the heat up at least two degrees. Opps, I see my mistake. It should have been 2350 W average. I don't think I would like a bill of 2350 kW for a month. -- Rick C
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-14 17:34 -0500 |
| Message-ID | <o800ic$eo7$2@dont-email.me> |
| In reply to | #447659 |
On 2/14/2017 3:53 PM, dagmargoodboat@yahoo.com wrote: > On Tuesday, February 14, 2017 at 2:16:49 PM UTC-5, rickman wrote: >> On 2/14/2017 9:56 AM, dagmargoodboat@yahoo.com wrote: >>> 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). >> >> Your number for electricity usage is a bit low. My usage last bill was >> 2350 kW average. 1692 kWhr / 720 hr = 2.35 kW costing under $200. Was >> your bill in the $20 range? If not I suspect you missed a decimal point. > > Why do you seem never to believe other people? I used 207 kWhr, > and yes, paid about $20 plus $10 service charge. Ok, ignore my other post then. I'm not sure what relevance this has. I guess just an observation. -- Rick C
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| From | bill.sloman@ieee.org |
|---|---|
| Date | 2017-02-12 04:57 -0800 |
| Message-ID | <57391011-b807-4597-b2e6-bdb26cd2d51e@googlegroups.com> |
| In reply to | #447381 |
On Sunday, February 12, 2017 at 5:02:38 PM UTC+11, 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. 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??? The fact that you could feel a draft. > > 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. Making the gap too big allows convention currents between the panes. Styrofoam is essentially stabilised air - the individual cells are too small to allow convection. > > 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 "ultra-fine" temperature controller was aimed a getting tight control of temperature over a volume about 1cm square and less than a millimetre thick. As the paper said, we could have done better if we could have insulated the volume of interest better, and hadn't had to leave clear spaces for access. You want to get rid of a specific temperature gradient, essentially from the middle of your window to the wall surrounding it. Putting a heat source in the middle of your window may well do it. The high-tech solution - as used in car windows which you don't want to mist up - is an electrically conductive and transparent layer of tin oxide. http://www.techbriefs.com/component/content/article/ntb/tech-briefs/materials/3363 > 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. Curtain? A draft is just a convection current, and if you confine that convection current so that it doesn't actually run down you back, you should be fine. If you wanted to go very high tech, you could work out the Rayleigh number. https://en.wikipedia.org/wiki/Rayleigh_number It does depend on the cube of the characteristic length, and making the convecting volume thin does help. -- Bill Sloman, Sydney
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-12 18:19 -0500 |
| Message-ID | <o7qqf9$bj9$1@dont-email.me> |
| In reply to | #447400 |
On 2/12/2017 7:57 AM, bill.sloman@ieee.org wrote: > On Sunday, February 12, 2017 at 5:02:38 PM UTC+11, 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. 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??? > > The fact that you could feel a draft. Yeah, that's what I thought. I expect I would feel the draft from the wall if I were sitting with my back to that. It's not a windstorm, it's a slow, cool draft that makes my shoulders ache. >>> 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. > > Making the gap too big allows convention currents between the panes. > Styrofoam is essentially stabilised air - the individual cells are > too small to allow convection. >> >> 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 "ultra-fine" temperature controller was aimed a getting tight > control of temperature over a volume about 1cm square and less than a > millimetre thick. > > As the paper said, we could have done better if we could have > insulated the volume of interest better, and hadn't had to leave > clear spaces for access. > > You want to get rid of a specific temperature gradient, essentially > from the middle of your window to the wall surrounding it. > > Putting a heat source in the middle of your window may well do it. There is no reason on earth to heat the middle of the wall. Heating the surface would be much better, less heat loss to the outside. > The high-tech solution - as used in car windows which you don't want > to mist up - is an electrically conductive and transparent layer of > tin oxide. > > http://www.techbriefs.com/component/content/article/ntb/tech-briefs/materials/3363 > > >> 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. > > Curtain? A draft is just a convection current, and if you confine > that convection current so that it doesn't actually run down you > back, you should be fine. > > If you wanted to go very high tech, you could work out the Rayleigh > number. > > https://en.wikipedia.org/wiki/Rayleigh_number > > It does depend on the cube of the characteristic length, and making > the convecting volume thin does help. > -- Rick C
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| From | Winfield Hill <hill@rowland.harvard.edu> |
|---|---|
| Date | 2017-02-12 10:42 -0800 |
| Message-ID | <o7qa9r02j2s@drn.newsguy.com> |
| In reply to | #447381 |
rickman wrote...
>
> 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.
A wire-strip heater at the bottom could create an internal
circulation to heat the small gap a little, and create a
light surface draft that goes up instead of down. Would
such a draft also be a problem?
--
Thanks,
- Win
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-12 18:30 -0500 |
| Message-ID | <o7qr3s$eb6$1@dont-email.me> |
| In reply to | #447438 |
On 2/12/2017 1:42 PM, Winfield Hill wrote: > rickman wrote... >> >> 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. > > A wire-strip heater at the bottom could create an internal > circulation to heat the small gap a little, and create a > light surface draft that goes up instead of down. Would > such a draft also be a problem? No, that was my original idea. But I find resistance wire to be a PITA compared to using resistors. I had thought of using surface mount parts scattered across some circuit board strips, but found 100 watt resistors on eBay for a buck apiece. I initially used a bench supply and found 15 to 20 volts would do the job ok. So I pulled out an old laptop supply and it works great. I think I'm going to mount the resistors to an aluminum plate with some wood trim so it fills the bottom foot of the window. I'll add a second bank so the two halves can be heated independently. Use a "universal" laptop supply so the voltage can be adjusted just so and it should keep me warm all winter. Not so cheap, but no more than any of the heating plates I found on the Internet including from Aliexpress. The only hard part is cutting the plate to length, but I know someone with metal tools who can do this for me. -- Rick C
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| From | Tom Gardner <spamjunk@blueyonder.co.uk> |
|---|---|
| Date | 2017-02-12 08:45 +0000 |
| Message-ID | <WgVnA.352959$fs3.153333@fx14.am4> |
| In reply to | #447373 |
On 12/02/17 04:57, 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. > > 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. There are two cheaper versions. One: take clingfilm and sticky tape it to the window frame, then play a hairdryer over it to make it taught. Optionally replace the tape with whiteboard magnets, to make it a little removable. Two: gardeners insulate their greenhouses with double-walled bubble wrap. I presume you could also use two layers of single-walled bubble wrap, which would be easier to obtain for a quick-and-dirty experiment. Both have the advantages of allowing light through and stopping draughts around the window, and help to reduce heat loss. I doubt either would be very effective for the OP's case. I suspect the OP's other options would be to wear an anorak/salopettes, or to have a baffle that guides the draught elsewhere in the room.
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-12 03:57 -0500 |
| Message-ID | <o7p7uq$r39$1@dont-email.me> |
| In reply to | #447389 |
On 2/12/2017 3:45 AM, Tom Gardner wrote: > On 12/02/17 04:57, 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. >> >> 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. > > There are two cheaper versions. > > One: take clingfilm and sticky tape it to the window > frame, then play a hairdryer over it to make it taught. > Optionally replace the tape with whiteboard magnets, > to make it a little removable. > > Two: gardeners insulate their greenhouses with double-walled > bubble wrap. I presume you could also use two layers > of single-walled bubble wrap, which would be easier > to obtain for a quick-and-dirty experiment. > > Both have the advantages of allowing light through and > stopping draughts around the window, and help to reduce > heat loss. > > I doubt either would be very effective for the OP's case. > > I suspect the OP's other options would be to wear an > anorak/salopettes, or to have a baffle that guides > the draught elsewhere in the room. I balk at putting tons of insulation on myself, but I tried redirecting the draft. I used to have a piece of cardboard behind the blinds that tended to keep the draft at the edges. It sort of worked, but only if I stayed right in the one spot. I would add the plastic, but when I've done that before the tape provided is pretty marginal and comes loose pretty easily. Also, for some reason the varnish on my window tends to come off with the tape. It may have some water damage. -- Rick C
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| From | Tom Gardner <spamjunk@blueyonder.co.uk> |
|---|---|
| Date | 2017-02-12 09:34 +0000 |
| Message-ID | <2%VnA.767760$La3.277159@fx38.am4> |
| In reply to | #447391 |
On 12/02/17 08:57, rickman wrote: > On 2/12/2017 3:45 AM, Tom Gardner wrote: >> On 12/02/17 04:57, 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. >>> >>> 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. >> >> There are two cheaper versions. >> >> One: take clingfilm and sticky tape it to the window >> frame, then play a hairdryer over it to make it taught. >> Optionally replace the tape with whiteboard magnets, >> to make it a little removable. >> >> Two: gardeners insulate their greenhouses with double-walled >> bubble wrap. I presume you could also use two layers >> of single-walled bubble wrap, which would be easier >> to obtain for a quick-and-dirty experiment. >> >> Both have the advantages of allowing light through and >> stopping draughts around the window, and help to reduce >> heat loss. >> >> I doubt either would be very effective for the OP's case. >> >> I suspect the OP's other options would be to wear an >> anorak/salopettes, or to have a baffle that guides >> the draught elsewhere in the room. > > I balk at putting tons of insulation on myself, Consider using less electricity by plugging yourself into the mains. Not directly, but via one of those things for the elderly that is effectively a 1 sq ft electric blanket for keeping the kidneys warm. Or occasionally sticking a hairdryer's outlet under your sweater :) > but I tried redirecting the > draft. I used to have a piece of cardboard behind the blinds that tended to > keep the draft at the edges. It sort of worked, but only if I stayed right in > the one spot. Yes, it would only shift the problem :) A long curtain should could deflect the draught down to floor level. Blinds, whatever that means, seem pretty sub-optimum. > I would add the plastic, but when I've done that before the tape provided is > pretty marginal and comes loose pretty easily. Also, for some reason the > varnish on my window tends to come off with the tape. It may have some water > damage. Painters "masking tape" is low adhesive, since it is designed to be removed. No guarantees though.
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| From | Jon Elson <elson@pico-systems.com> |
|---|---|
| Date | 2017-02-11 23:52 -0600 |
| Message-ID | <CpOdnSRg_MKBZQLFnZ2dnUU7-TGdnZ2d@giganews.com> |
| In reply to | #447363 |
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. Try facing the styrofoam with kitchen aluminum foil (unless you want light to come through, of course.) It will be an IR reflector, and may substantially improve the insulation effect of the styrofoam. Jon
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-12 01:07 -0500 |
| Message-ID | <o7otv1$3dj$1@dont-email.me> |
| In reply to | #447379 |
On 2/12/2017 12:52 AM, Jon Elson wrote: > 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. > > Try facing the styrofoam with kitchen aluminum foil (unless you want light > to come through, of course.) It will be an IR reflector, and may > substantially improve the insulation effect of the styrofoam. That would help if there was much temperature difference. But the inside is only three degrees (F) different from the rest of the room. Maybe the temperature difference on the other side is greater. But 3/4 inches of Styrofoam is a *lot* of insulation. I believe it is equivalent to four inches of fiberglass. I think the insulation is very good at this point. The problem is there will always be *some* heat loss and it doesn't take very much at all to create a draft albeit a small one. The issue is not so much that there is a draft even, it wouldn't be noticed if I didn't have my back right up to it. Hmmmm. the heater is toasty! -- Rick C
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| From | Martin Brown <|||newspam|||@nezumi.demon.co.uk> |
|---|---|
| Date | 2017-02-14 10:40 +0000 |
| Message-ID | <o7umr7$64j$2@gioia.aioe.org> |
| In reply to | #447382 |
On 12/02/2017 06:07, rickman wrote: > On 2/12/2017 12:52 AM, Jon Elson wrote: >> 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. >> >> Try facing the styrofoam with kitchen aluminum foil (unless you want >> light >> to come through, of course.) It will be an IR reflector, and may >> substantially improve the insulation effect of the styrofoam. Not always substantial unless radiative transfer is significant (usually at round 30C temperature difference) but it prevents hot spots and cold spots by equalising the temperature at the radiation barrier. > > That would help if there was much temperature difference. But the > inside is only three degrees (F) different from the rest of the room. > Maybe the temperature difference on the other side is greater. But 3/4 > inches of Styrofoam is a *lot* of insulation. I believe it is > equivalent to four inches of fiberglass. There is always some heat loss with any real materials, but even a relatively thin piece of styrofoam is warm to the touch so I don't see how it can support a noticeable draft unless you have liquid air on the other side of your window. How cold is cold in this context? > I think the insulation is very good at this point. The problem is there > will always be *some* heat loss and it doesn't take very much at all to > create a draft albeit a small one. The issue is not so much that there > is a draft even, it wouldn't be noticed if I didn't have my back right > up to it. Divert the draft to one side then? > > Hmmmm. the heater is toasty! One which might do what you want is the twinwall polycarbonate used with the channels running horizontal as an inner insulating layer. I think you need to figure out where the draft is actually coming from. Something isn't right here. -- Regards, Martin Brown
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-14 06:00 -0500 |
| Message-ID | <o7unu1$n64$1@dont-email.me> |
| In reply to | #447629 |
On 2/14/2017 5:40 AM, Martin Brown wrote: > On 12/02/2017 06:07, rickman wrote: >> On 2/12/2017 12:52 AM, Jon Elson wrote: >>> 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. >>> >>> Try facing the styrofoam with kitchen aluminum foil (unless you want >>> light >>> to come through, of course.) It will be an IR reflector, and may >>> substantially improve the insulation effect of the styrofoam. > > Not always substantial unless radiative transfer is significant (usually > at round 30C temperature difference) but it prevents hot spots and cold > spots by equalising the temperature at the radiation barrier. >> >> That would help if there was much temperature difference. But the >> inside is only three degrees (F) different from the rest of the room. >> Maybe the temperature difference on the other side is greater. But 3/4 >> inches of Styrofoam is a *lot* of insulation. I believe it is >> equivalent to four inches of fiberglass. > > There is always some heat loss with any real materials, but even a > relatively thin piece of styrofoam is warm to the touch so I don't see > how it can support a noticeable draft unless you have liquid air on the > other side of your window. How cold is cold in this context? Hard to measure the temperature of something on the other side of a piece of Styrofoam. If you check, you will find there is a slow moving draft off your walls. The fact that your hand will warm up a piece of Styrofoam means nothing compared to the small amount of heat required to warm air. Styrofoam feels warm to the touch for the same reason room temperature marble feels cold to the touch, thermal mass, not temperature. >> I think the insulation is very good at this point. The problem is there >> will always be *some* heat loss and it doesn't take very much at all to >> create a draft albeit a small one. The issue is not so much that there >> is a draft even, it wouldn't be noticed if I didn't have my back right >> up to it. > > Divert the draft to one side then? That's already been discussed. >> Hmmmm. the heater is toasty! > > One which might do what you want is the twinwall polycarbonate used with > the channels running horizontal as an inner insulating layer. I think > you need to figure out where the draft is actually coming from. > > Something isn't right here. If you think the draft isn't from the cold coming through the wall and window, then what isn't right is your thinking. We aren't talking about Niagra Falls. It is a very slow moving draft only a few degrees cooler than the room temperature. Heck, it might not even be that the air is cooler than the rest of the room. It may well just be that the air is constantly moving over my shoulders disturbing the warm boundary layer of air around my body. It's much better with a warm draft replacing the warm layers of air around my body. -- Rick C
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| From | John S <Sophi.2@invalid.org> |
|---|---|
| Date | 2017-02-14 16:17 -0600 |
| Message-ID | <o7vvih$cd9$2@dont-email.me> |
| In reply to | #447630 |
On 2/14/2017 5:00 AM, rickman wrote: > On 2/14/2017 5:40 AM, Martin Brown wrote: >> On 12/02/2017 06:07, rickman wrote: >>> On 2/12/2017 12:52 AM, Jon Elson wrote: >>>> 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. >>>> >>>> Try facing the styrofoam with kitchen aluminum foil (unless you want >>>> light >>>> to come through, of course.) It will be an IR reflector, and may >>>> substantially improve the insulation effect of the styrofoam. >> >> Not always substantial unless radiative transfer is significant (usually >> at round 30C temperature difference) but it prevents hot spots and cold >> spots by equalising the temperature at the radiation barrier. >>> >>> That would help if there was much temperature difference. But the >>> inside is only three degrees (F) different from the rest of the room. >>> Maybe the temperature difference on the other side is greater. But 3/4 >>> inches of Styrofoam is a *lot* of insulation. I believe it is >>> equivalent to four inches of fiberglass. >> >> There is always some heat loss with any real materials, but even a >> relatively thin piece of styrofoam is warm to the touch so I don't see >> how it can support a noticeable draft unless you have liquid air on the >> other side of your window. How cold is cold in this context? > > Hard to measure the temperature of something on the other side of a > piece of Styrofoam. If you check, you will find there is a slow moving > draft off your walls. The fact that your hand will warm up a piece of > Styrofoam means nothing compared to the small amount of heat required to > warm air. Styrofoam feels warm to the touch for the same reason room > temperature marble feels cold to the touch, thermal mass, not temperature. > > >>> I think the insulation is very good at this point. The problem is there >>> will always be *some* heat loss and it doesn't take very much at all to >>> create a draft albeit a small one. The issue is not so much that there >>> is a draft even, it wouldn't be noticed if I didn't have my back right >>> up to it. >> >> Divert the draft to one side then? > > That's already been discussed. > > >>> Hmmmm. the heater is toasty! >> >> One which might do what you want is the twinwall polycarbonate used with >> the channels running horizontal as an inner insulating layer. I think >> you need to figure out where the draft is actually coming from. >> >> Something isn't right here. > > If you think the draft isn't from the cold coming through the wall and > window, then what isn't right is your thinking. We aren't talking about > Niagra Falls. It is a very slow moving draft only a few degrees cooler > than the room temperature. Heck, it might not even be that the air is > cooler than the rest of the room. It may well just be that the air is > constantly moving over my shoulders disturbing the warm boundary layer > of air around my body. > > It's much better with a warm draft replacing the warm layers of air > around my body. > Have you tried putting on a coat?
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| From | Lasse Langwadt Christensen <langwadt@fonz.dk> |
|---|---|
| Date | 2017-02-14 14:28 -0800 |
| Message-ID | <116f8629-9e3f-40e8-9f93-18d192fa883b@googlegroups.com> |
| In reply to | #447665 |
Den tirsdag den 14. februar 2017 kl. 23.17.38 UTC+1 skrev John S: > On 2/14/2017 5:00 AM, rickman wrote: > > On 2/14/2017 5:40 AM, Martin Brown wrote: > >> On 12/02/2017 06:07, rickman wrote: > >>> On 2/12/2017 12:52 AM, Jon Elson wrote: > >>>> 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. > >>>> > >>>> Try facing the styrofoam with kitchen aluminum foil (unless you want > >>>> light > >>>> to come through, of course.) It will be an IR reflector, and may > >>>> substantially improve the insulation effect of the styrofoam. > >> > >> Not always substantial unless radiative transfer is significant (usually > >> at round 30C temperature difference) but it prevents hot spots and cold > >> spots by equalising the temperature at the radiation barrier. > >>> > >>> That would help if there was much temperature difference. But the > >>> inside is only three degrees (F) different from the rest of the room. > >>> Maybe the temperature difference on the other side is greater. But 3/4 > >>> inches of Styrofoam is a *lot* of insulation. I believe it is > >>> equivalent to four inches of fiberglass. > >> > >> There is always some heat loss with any real materials, but even a > >> relatively thin piece of styrofoam is warm to the touch so I don't see > >> how it can support a noticeable draft unless you have liquid air on the > >> other side of your window. How cold is cold in this context? > > > > Hard to measure the temperature of something on the other side of a > > piece of Styrofoam. If you check, you will find there is a slow moving > > draft off your walls. The fact that your hand will warm up a piece of > > Styrofoam means nothing compared to the small amount of heat required to > > warm air. Styrofoam feels warm to the touch for the same reason room > > temperature marble feels cold to the touch, thermal mass, not temperature. > > > > > >>> I think the insulation is very good at this point. The problem is there > >>> will always be *some* heat loss and it doesn't take very much at all to > >>> create a draft albeit a small one. The issue is not so much that there > >>> is a draft even, it wouldn't be noticed if I didn't have my back right > >>> up to it. > >> > >> Divert the draft to one side then? > > > > That's already been discussed. > > > > > >>> Hmmmm. the heater is toasty! > >> > >> One which might do what you want is the twinwall polycarbonate used with > >> the channels running horizontal as an inner insulating layer. I think > >> you need to figure out where the draft is actually coming from. > >> > >> Something isn't right here. > > > > If you think the draft isn't from the cold coming through the wall and > > window, then what isn't right is your thinking. We aren't talking about > > Niagra Falls. It is a very slow moving draft only a few degrees cooler > > than the room temperature. Heck, it might not even be that the air is > > cooler than the rest of the room. It may well just be that the air is > > constantly moving over my shoulders disturbing the warm boundary layer > > of air around my body. > > > > It's much better with a warm draft replacing the warm layers of air > > around my body. > > > > Have you tried putting on a coat? cloak or superhero cape? :P
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| From | rickman <gnuarm@gmail.com> |
|---|---|
| Date | 2017-02-14 17:36 -0500 |
| Message-ID | <o800lj$eo7$4@dont-email.me> |
| In reply to | #447665 |
On 2/14/2017 5:17 PM, John S wrote: > On 2/14/2017 5:00 AM, rickman wrote: >> On 2/14/2017 5:40 AM, Martin Brown wrote: >>> On 12/02/2017 06:07, rickman wrote: >>>> On 2/12/2017 12:52 AM, Jon Elson wrote: >>>>> 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. >>>>> >>>>> Try facing the styrofoam with kitchen aluminum foil (unless you want >>>>> light >>>>> to come through, of course.) It will be an IR reflector, and may >>>>> substantially improve the insulation effect of the styrofoam. >>> >>> Not always substantial unless radiative transfer is significant (usually >>> at round 30C temperature difference) but it prevents hot spots and cold >>> spots by equalising the temperature at the radiation barrier. >>>> >>>> That would help if there was much temperature difference. But the >>>> inside is only three degrees (F) different from the rest of the room. >>>> Maybe the temperature difference on the other side is greater. But 3/4 >>>> inches of Styrofoam is a *lot* of insulation. I believe it is >>>> equivalent to four inches of fiberglass. >>> >>> There is always some heat loss with any real materials, but even a >>> relatively thin piece of styrofoam is warm to the touch so I don't see >>> how it can support a noticeable draft unless you have liquid air on the >>> other side of your window. How cold is cold in this context? >> >> Hard to measure the temperature of something on the other side of a >> piece of Styrofoam. If you check, you will find there is a slow moving >> draft off your walls. The fact that your hand will warm up a piece of >> Styrofoam means nothing compared to the small amount of heat required to >> warm air. Styrofoam feels warm to the touch for the same reason room >> temperature marble feels cold to the touch, thermal mass, not >> temperature. >> >> >>>> I think the insulation is very good at this point. The problem is >>>> there >>>> will always be *some* heat loss and it doesn't take very much at all to >>>> create a draft albeit a small one. The issue is not so much that there >>>> is a draft even, it wouldn't be noticed if I didn't have my back right >>>> up to it. >>> >>> Divert the draft to one side then? >> >> That's already been discussed. >> >> >>>> Hmmmm. the heater is toasty! >>> >>> One which might do what you want is the twinwall polycarbonate used with >>> the channels running horizontal as an inner insulating layer. I think >>> you need to figure out where the draft is actually coming from. >>> >>> Something isn't right here. >> >> If you think the draft isn't from the cold coming through the wall and >> window, then what isn't right is your thinking. We aren't talking about >> Niagra Falls. It is a very slow moving draft only a few degrees cooler >> than the room temperature. Heck, it might not even be that the air is >> cooler than the rest of the room. It may well just be that the air is >> constantly moving over my shoulders disturbing the warm boundary layer >> of air around my body. >> >> It's much better with a warm draft replacing the warm layers of air >> around my body. >> > > Have you tried putting on a coat? Yes, I do, every time I go out. :) -- Rick C
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| From | Mikko OH2HVJ <mikko.syrjalahti@nospam.fi> |
|---|---|
| Date | 2017-02-12 14:54 +0200 |
| Message-ID | <m2k28v4liu.fsf@nospam.fi> |
| In reply to | #447363 |
rickman <gnuarm@gmail.com> writes: > 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. The setup is not completely clear to me, is it a vertical window in the wall, horizontal in the roof or an angled one ? In Finland where we can have -30°C outside the typical solution is an argon filled 2 or 3 pane window with low-e coatings and a radiator under the window. The radiator creates an upward airflow, which keeps the feeling of draft away. Typical power is 50-200W or 500-700W if you heat the room with the same ones. -- mikko
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| From | Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> |
|---|---|
| Date | 2017-02-12 08:56 -0700 |
| Message-ID | <s911ac54qj7t1t11l12d10a9jha23vdc4v@4ax.com> |
| In reply to | #447399 |
On Sun, 12 Feb 2017 14:54:33 +0200, Mikko OH2HVJ
<mikko.syrjalahti@nospam.fi> wrote:
>rickman <gnuarm@gmail.com> writes:
>
>> 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.
>
>The setup is not completely clear to me, is it a vertical window in the
>wall, horizontal in the roof or an angled one ?
>
>In Finland where we can have -30°C outside the typical solution is an
>argon filled 2 or 3 pane window with low-e coatings and a radiator under
>the window. The radiator creates an upward airflow, which keeps the
>feeling of draft away. Typical power is 50-200W or 500-700W if you heat the
>room with the same ones.
It's been in the low 80°F's here the last few days, but colder today,
only 75°F (24°C >:-}
I hate cold... that's why I came straight to Arizona upon graduating
from MIT in 1962.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Thinking outside the box... producing elegant solutions.
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