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<DIV><SPAN class=703034723-14032012><FONT face=Arial color=#0000ff size=2>Not to
me. </FONT></SPAN></DIV>
<DIV> </DIV>
<DIV><SPAN class=703034723-14032012></SPAN><FONT face=Arial><FONT
color=#0000ff><FONT
size=2>I don't know anything about drain back systems but my understanding is that:</FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT color=#0000ff><FONT
size=2></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>1. </SPAN>I<SPAN class=703034723-14032012>f you use a
closed loop glycol collector, you don't need drain
back</SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>2, If you just use water, you drain the water and
refill it the next morning - with water , which I guess goes quite soem
way to explain why people use
glycol.</SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>In the article alluded
to</SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>1. They don't seem to draw any distinction between open
and closed loop systems. </SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>2. they glibly talk about an oversized heat exchanger.
This may be detrimental to the heat exchanger performing its prime function -
namely, exchanging heat.</SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>3. It seems that they must have air in the circlation
system. This would be fatal to collector
efficiency</SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>4. The actual collector must be the worst design ever.
I have never actually seen a serpentine design like that in actual production.
The only place where you would see anything like that is in an article
showing how not to do it. </SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012> Even if there is no need to distinguish between
open and close loop systems, and the heat exchanger is OK, and they have some
secret air relief device, who on earth would take Wagner Solar seriously, when
they have a collector like
that? </SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012>I don't know who the smiling guys are at the top of the
page, but they could certainly do with asking some questions. Maybe they are
just salesmen quoting a press
handout. </SPAN></FONT></FONT></FONT></FONT></FONT></DIV>
<DIV><FONT><FONT><FONT face=Arial><FONT color=#0000ff><FONT size=2><SPAN
class=703034723-14032012></SPAN></FONT></FONT></FONT></FONT></FONT> </DIV>
<DIV><SPAN class=703034723-14032012></SPAN><FONT face=Arial><FONT
color=#0000ff><FONT size=2>A<SPAN class=703034723-14032012>nd another thing. Why
would you use a second heat exchanger system for backup? Surely it is simpler to
just install an electric element at the bottom of the tank like everybody else
does? </SPAN></FONT></FONT></FONT><BR></DIV>
<P><FONT size=2>Nick Pyner<BR><BR>Dee Why NSW </FONT></P>
<BLOCKQUOTE>
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
greenbuilding-bounces@lists.bioenergylists.org
[mailto:greenbuilding-bounces@lists.bioenergylists.org]<B>On Behalf Of
</B>Sacie Lambertson<BR><B>Sent:</B> Wednesday, 14 March 2012 7:06
AM<BR><B>To:</B> Greenbuilding<BR><B>Subject:</B> [Greenbuilding] new solar
heating system in this country<BR><BR></FONT></DIV><FONT size=+0><FONT
face=verdana,sans-serif>This sounds very good to me:<BR><BR><A
href="http://www.buildinggreen.com/live/index.cfm/2012/3/13/German-Innovation-in-Solar-Water-Heating">http://www.buildinggreen.com/live/index.cfm/2012/3/13/German-Innovation-in-Solar-Water-Heating</A><BR></BLOCKQUOTE></FONT></FONT></BODY></HTML>