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    When is Delta T for heating not a true Delta T?? (29 Posts)

  • Mark Eatherton Mark Eatherton @ 9:59 AM
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    When is Delta T for heating not a true Delta T??

    When the sky has no clouds!

    Take a look at this photograph. I took it early in the morning, before any solar influence, and the lowest OSA temp seen that night was -3.5 degrees F.

    I've had hotel mechanical engineers up here in the mountains tell me that their decision as to whether they need one boilers or two was based more on whether there were going to be clouds that night versus the lowest air temperature potential.

    Interesting stuff to say the least... Comments?

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mark Eatherton Mark Eatherton @ 10:00 AM
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    Picture

    here
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mark Eatherton Mark Eatherton @ 7:20 PM
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    Radiant windows from theoutside...

    As viewed from 75 feet away...
    Furthest right window off, next two running at 90 degrees F, next three running at 80 degrees F, and last four on left running at 70 degrees F (Thermally opaque condition).

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mark Eatherton Mark Eatherton @ 7:35 PM
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    Radiant windows form the inside...

    Far left window off, balance of them are on with some hotter than others (obviously). The furthest windows are in the thermally opaque mode, maintaining around 70 to 75 degrees F. In other words, as it pertains to conventional room heat loss, they are not there... and this is what I think is the MOST efficient mode.

    Induced R value :-)

    Anyone care to tender a guess as to what R value of window would be required to maintain a room side surface temperature of 70 + degrees F?

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    This post was edited by an admin on December 20, 2009 7:37 PM.
  • Mark Eatherton Mark Eatherton @ 7:39 PM
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    Picture one

    For some reason, I can't post two pictures at the same time,,,

    Figured it out. I was trying to attch th IR extenion file photos and not the JPEG extention photos...

    My bad :-)
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    This post was edited by an admin on December 20, 2009 7:54 PM.
  • Chris Chris @ 7:59 PM
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    I'll Give It a try

    I have a questions first. What time value are you stamping on that room side temp?
    Ti-To divided by R-Value = Heat Loss of an outside panel
    Ti = Temp Indoor
    T0= Temp Outdoor
    I would have to have a R-value that exceeds Ti in order to have no loss at all. But I'll bite and say. For under 15 minutes a 2.77 for 3 minutes a .55
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Mark Eatherton Mark Eatherton @ 8:14 PM
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    Sure....

    One hour, Ti of the glass is 70 degrees F, and To of the glass is 0 degrees F, same as the OSA.

    Un-energized, the glass has a conventional R value of 2.5, and the corresponding glass surface temeprature at zero degrees F was 55 degrees F.

    What do you think the R value would be?

    ME

    PS, What about the glass that is 90 dergees F? Same other parameters.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Chris Chris @ 7:46 AM
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    I''ll have to think

    this out throughout the day. I'll get you an anwser tonight. Buys day today..Alot of no heats.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • bob bob @ 3:27 PM
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    Delta T= change in trickyness

    Mark, I think this is a trick question or at least a tricky one. First, R factor is the reciprocal of U factor by definition. U is the amount of heat transfered in BTU/hr/sq.ft/ Fº ∆T. If the temperature of the window is 70 Fº and the space is 70 Fº the ∆T = 0 , so U =0 there is no heat transfer from the space to the window. The R factor would be infinite. To determine the amount of heat given off to the out side air just measure how many watts gozinta the window and multiply by 3.413 BTU.
    bob
    This post was edited by an admin on December 21, 2009 3:34 PM.
  • Mark Eatherton Mark Eatherton @ 9:07 PM
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    Great minds think alike bob...

    But I have told everyone involved with the project to not use those terms, because it causes professional to do a double take, and curl their noses....

    But essentially, it is what it is, adjustable and infinite.


    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • N/A @ 9:17 PM

    Blowing Your Own Horn,,,,

    Geezze Mark,,,,, 7 out of 10 postings are yours,,,, give your ego a rest,,, please!
  • Mark Eatherton Mark Eatherton @ 9:25 PM
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    If I don't blow it, who will....

    And I have no ego Dave. Only a desire to educate, and not criticize like some people....

    Who's counting? Who's commenting?

    If you had something as hot as these windows, you be honking about it too.... ;-)

    And you don't have to read anything I write. Just ignore my posts.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • TonyS TonyS @ 9:43 PM
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    How many watts are

    those windows using?
  • Mark Eatherton Mark Eatherton @ 7:30 AM
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    Tony S....

    Bear with me. I just pulled the data loggers from the site and have a LOT of information togo through and decipher. I will be able to answer your question shortly for two different modes, one for opaque condition (maintaining the glass at around 70 to 75 degrees F) and the other at a higher thermally productive mode.

    Thanks for your patience.

    Just like with hydronics, the only correct answer to any question is, IT DEPENDS! What size of glass under what operating conditions.

    Bear with me.


    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • TonyS TonyS @ 12:57 PM
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    This will be interesting!

    Keep us informed. I would imagine there are uses for this glass beyond buildings. Like a zoo or aquarium,terrarium that houses tropical type animals. And Dave, this stuff is interesting!!, and Mark is always willing to share, so let him alone.
  • N/A @ 10:02 PM

    No Ego???

    Holy-heck everyones focused on "The Great ME" I would think,,, but there comes a time.

    Personally, i think no-one but yourself gives a damn for products your promoting, & yourself,,, in thinking of your superiority.

    I DO choose not to read your posts,,,,, but you post SO-OFTEN avoiding you is not a luxury I can afford myself as much as I would like.
  • NRT_Rob NRT_Rob @ 8:13 AM
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    dave, you're wrong

    many of us out here are interested in mark's radiant windows and what they can do.

    If you are not, ignore the whole thread. easy.
    NRT.Rob
  • Dan Holohan Dan Holohan @ 12:12 PM
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    Nasty, Dave.

    You're disappointing me.
    Site Administrator
    dan@heatinghelp.com













    Hug your kids.
  • Chris Chris @ 6:09 AM
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    Keep Up The Great Work Mark

    I enjoy your posts. Keeps the mind fresh. I was stumped on this one. Keep up the great work.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Mark Eatherton Mark Eatherton @ 7:31 AM
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    Chris...

    I've been stumped for almost three years :-)

    Thanks for the input.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • MIke_Jonas MIke_Jonas @ 10:28 PM
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    Keep posting Mark!!

    I read your stuff every time I see your name.

    I think about you almost every day...in a purely hetero, Viking sort of way..let me 'splain...

    My office is in the front of my house. West side of Chicago (Berwyn). I have a 5 1/2' x 5 1/2' single pane window, with a transom like 5 1/2' x 18" single pane window above it.

    I don't need no stinkin' R values to tell you the chill I feel as I sit at my desk do I?

    So I meet you at Rexpo in Schaumburg and see/touch/feel your window display, in a purely hetero, Viking sort of way. Blows me away. The possiblities are endless. MegaMillions Lottery is something like 166 jillion tomorrow night, savi?

    So, every morning, in winter, I walk into my office and say to myself..."Dang, I got to remodel this room and get me some of them ME windows in here."
  • L'town Radiant L'town Radiant @ 11:47 AM
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    Dave needs

    an attitude adjustment....if you don't have anything nice, just don't say anything.
    Mark, I recall seeing you display this product at the RPA show last year, It was impressive but it didn't have hot water running through it so I didn't spend much time on it. I'd have to say that this definately deserves some more consideration. Can you direct me to a website where I could study up on it?
    Oh, and I'm always glad to see a post by the "Great ME"
    A warm floor warms my heart!
  • bill garnett bill garnett @ 1:55 PM
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    Radiant Windows

    ME,
    I have not posted since the walls new format-I love your post's !!! Always informative not sure why Dave is so jealous ?
  • Gordy Gordy @ 5:39 PM
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    I for one

    Appreciate Mark sharing the information he has collected on these radiant windows. Been following his threads on these since his first posting of them. Been following his threads since I first found this site 10 years ago.

    Mark always has something PRODUCTIVE to say, and share on everything.....I do not believe sharing knowledge is egotistical.

    Keep posting ME


    Gordy
    This post was edited by an admin on December 22, 2009 5:41 PM.
  • Chris Chris @ 6:14 PM
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    Knowledge is Power

    Mark I  enjot reading your posts. What makes this site great to me is the education you find in each post. I have been in the industry since 1989. So of consider this back in the day. Back then most supply houses were owned by mon and pop. There was always something educational going on. With corporations buying up these type of supply houses the of education you can get just from reading the posts here is priceless. Keep up the great work.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Dave Yates (GrandPAH) Dave Yates (GrandPAH) @ 8:57 AM
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    keep on posting!

    You're one of the main reasons why I visit here. Lots of others, but I tend to gravitate to posts I can pretty much be sure will have some substance. It's my old enemy - time - as in the lack thereof.

    So, keep on posting old friend and I'll keep on reading and learning!
  • hot rod hot rod @ 10:14 AM
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    ME is very generous

    with his knowledge and experimentations, and by now you should be aware of his unique style, Dave. Lighten up, it the holidays :)

    hr
  • Mark Eatherton Mark Eatherton @ 4:10 PM
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    I am humbled...

    and honored by the responses. Thank you for your support.

    I had no intention of leaving. Been here since day one and will be here till it closes (hopefully never) or they close the cover to my casket, which ever comes first ;-))

    Am just currently up to my ears in allligators, and the season. Will get back with more factual data as I get the chance.Dave, know that I hold no ill will towards you.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    This post was edited by an admin on December 23, 2009 4:11 PM.
  • Simply Rad Simply Rad @ 5:01 PM
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    ME for hydronic president!

    Through out the years I have found  those who do not understand tend to bad mouth.
    ME I can't thank you enough for all your knowledge and experiences! 
    Hail to hydronica. 
    By the way this site it designed to help and not harm.
    Happy Holidays

    Jeffrey
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