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Don Y[_3_]

On 12/6/2015 6:51 PM, wrote:
On Sun, 06 Dec 2015 20:03:06 -0500, Micky
wrote:

On Sun, 6 Dec 2015 17:26:46 -0500, Ron wrote:

My mom has a ceiling fan with a light kit. When the wall switch (single
toggle) is in the on (up) position the fan will run and when the switch
is in the off position (down) the fan stops running. OK, that is normal.

Here is the problem, the light will only turn on and off using the
chain, and it doesn't matter if the wall switch is in the on or off
position. Wall switch up, light turns on and off with chain. Wall switch
down, light turns on and off with chain. What is going on here?

BTW, this isn't a new problem. She bought the house 6 years ago and it
has just now been brought to my attention.

How does your mother want it to work.

Bear in mind, when the fan runs and no one is in the room, it doesn't
make the room cooler. It makes it warmer. The fan gives off a
little heat and moving air is equivalent to heat, plus it blows the
warm air near the ceiling down to where the people are. Not that fans
are bad -- most people like them -- but they don't help when you're
not in the room and you might want to turn the fan and the light off
then.
The fan still moves the air and keeps the temperature more even from
floor to ceiling. The amount of "heat" added to the room by the fan is
a virtual non issue.

Many fans have a direction switch (located *on* the fan itself -- often
a "slide" switch; usually arranged so sliding it towards the ceiling
causes rotation that moves air upward and sliding it towards the floor
reverses the direction so air moves downward).

Here, things get counterintuitive... :

Pushing air downward creates a bit of a draft on the occupants to
facilitate evaporative cooling (i.e. summer use). Pulling air upwards
ends up pushing the air trapped above the fan (displaced by the air
being drawn upwards) out to the walls and down into the room to heat the
room.

[Intuition suggest the opposite would be the case!]

Of course, the cooling effect only makes sense if there are
entities that can *perspire* in the air flow! A fan running
in an empty room doesn't cool ANYONE!