|
Posted by Bob F on July 1, 2008, 12:00 am
> Hi all,
>
> We have a newer two-speed attic furnace/HVAC unit which currently draws the
> intake from a hallway ceiling vent right next to where I would like to install
> a whole house fan to vent warm air into the attic to cool the house in the
> summer evenings rather than run the AC.
>
> I thought that we could use the existing two-speed furnace/AC blower to just
> divert the incoming air into the attic and have it double as a whole house
> fan. I think it would require some diverter valve to send the air into the
> attic rather than back through the plenum to return to the house, but this
> would obviate the need to cut new holes in the ceiling, install and wire a
> whole house fan, open up more ceiling space to heating and cooling losses,
> etc.
>
> Clearly it may be more work than it is worth, but I was wondering if anybody
> has tried something like this.
>
> We live in SoCal near the coast, so we have cool evenings regardless of the
> temperature during the day, and it makes a whole house fan an attractive
> option, particularly since we have a 5 ton AC unit with 169 LRA at 240 VAC
> (clearly oversized for our needs).
One problem would be that all the dust in the air you exhaust would be going
through the furnace, dirtying the heat exchangers and/or the filters. It would
be better to duck off the duct to the furnace for a separate fan, but that would
require a way to block the flow to/from the furnace to prevent backflow.
I have considered how I could duct outside air to the furnace intake for similar
results. with the outside air being filtered on the way into the house - a much
more desirable result. Some kind of controllable duct to a gable vent could make
this possible in your situation. Air would come from the inside, or the outside
gable vent.
| 
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap