[Tfug] *Way* OT: Swamp coolers, ACbrrs, etc.

[Bexley Hall]

--- Adrian <choprboy at dakotacom.net> wrote:

> On Wednesday 20 June 2007 18:38, Bexley Hall wrote:
> > 
> > > the house, run the swamp and the fan pressure
> opens
> > > the damper and hot air 
> > > flows into the return ductwork and out the
> rooftop
> > 
> > Hmmm... I was going to comment that this seems
> > similar to your previous comment re: only opening
> > *one* window.  But, I see a key difference here:
> > these homes have return ducts for the HVAC.
> > (our home has a wacky
> "furnace-in-the-middle-of-the-
> > house" scheme whereby the intake plenum is simply
> > the bottom of the furnace!  :< )
> 
> They make retrofit kits as well. Had to go look it
> up, they are called 
> "barometric dampers" and come in several forms. A

Yes, that's what we use to close off the furnace
output from the cooler and the cooler from the
furnace (i.e. so we can AC/heat and swamp cool
with the same ducts).  I am not sure I trust the
quality of their seals, though...

> couple I have seen either 
> take it directly off the AC return or, like my
> neighbor a couple doors down, 
> there is an exhaust duct in the ceiling of the
> central hall. One such example 
> of a retrofit kit is:
> http://www.updux.com/

I'll take a look.  Though I suspect it won't work in
our house (no place to put such a beast)
 
> And I found a handy-dandy table of cooler output
> temperature vs humidity and 
> outside temperature: 
>
http://www.homeenergy.org/archive/hem.dis.anl.gov/eehem/96/960511.html#96051128

Yes, I've some fancy math that attempts to relate
dewpoint/RH/wind speed/etc. for things like
heat index, wind chill, cooler efficiency, etc.
But, they're all just approximations (I guess
folks trying to fit Nth order polynomials to
empirical data) which never left me feeling very
confident  :<  (e.g., in pharmaceutical apps,
you often need to monitor dewpoint to know when
certain processes are finished, etc.)
 
> Time to start brushing up on PIC programming.



       
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