On Feb 11, 11:18*pm, Sylvia Else wrote:
On 11/02/2011 11:56 PM, kreed wrote:



On Feb 11, 9:20 pm, Sylvia *wrote:
On 11/02/2011 8:11 AM, ian field wrote:

"Sylvia * *wrote in message
...
On 10/02/2011 11:23 AM, Metro wrote:
"Sylvia * * wrote in message
...
I had occasion to dismantle a cheap pedestal fan the other day (Coles
Home
Collection). It hadn't failed, but I wanted to see how it was wired up
(that's another story).

The cover to the button panel was held in place by four screws which
were
identical except that two were philips head type, and the other two had
a
triangular socket in the head.

I have bits to cope with most things I've encountered, but not those.
What's the point? Are they worried about competition for repairing these
$10 fans?

Do consumers regularly electrocute themselves by taking fans apart
without
knowing what they're doing?

Sylvia.

They are only a tamperproof head of which there are various and easily
available.. Wait until you come across a coffin head screw.I believe the
reason for using them is that some countries prevent the dismantle of an
appliance without the use of a tool or special tool so this way all
fields
are covered in one assembly. Did you find out how it worked. They are
made
to break. Best way to keep them longer is to keep the Blades clean and
lubricate the bearings NOT with WD40 or the like.

As I said, it hadn't broken. I was actually trying to figure out which
wire was which leading to the induction motor. I had in mind making it run
backwards. Aerofoils don't perform as well backwards, but they do perform.
However, on further consideration I realised that the fan blades would be
aerodynamically stalled if the fan ran backwards, with the result that it
would probably not work much at all.

If the fan is symetrical - snap off pairs of opposing blades.

That's not going to fix the problem of the blades being stalled.

What I would really need to do is fit the one-piece fan blade assembly
on back to front (as well as reversing the motor), but the fan blade
assembly is not designed to be attached the other way around.

Sylvia.

Might sound silly, but cant the entire fan head (including motor) be
rotated 180 degrees, or do you want the
air intake without the motor in the way ?

The application is to suck cool air in through an open window at night.
During the recent heat wave, it was noticeable that even though the
temperature outside drops at night, the temperature of the house doesn't
drop that much. The problem is lack of air flow.


A conventional pedestal fan blows in such a direction that when it's
placed as near as possible to a window, the fan blades are still quite a
way from the cool air, and so the result is not as effective as it might
be. If I could reverse the direction of flow, then I could also turn
then fan around, so that the blades would be much closer to the window.

I considered simply building a duct, but the cost of materials was
excessive.

I'm thinking of using box fans instead.

Sylvia.

We had the same problem, I put a Woolies pedestal fan right in front
of the window on the inside, and used it that way. It works well, but
I agree that
if you could mount it in the open window directly it would work a lot
better. Currently
it sits about 25cm inside of the window opening due to the stand.


The box fan would probably be a better idea. Could put a shelf or
something under
the window, and sit it on there.

Another (depending on the amount of air these things move, their
appearance,
and the fact that the shaded pole motor and blade is exposed on the
back)
could be use bathroom type exhaust fan(s) mounted through a piece of
plywood
that sits in the open section of the window. ?

If the window has a good height,
you might be able to try one at the top blowing out the hot air and
one at the bottom blowing in cool ?