On Jun 20, 10:21*pm, Martin Levac wrote:
Hello,

I have a Lasko 2155A window fan with integrated 3 speed control unit
(links at the end of this post). I want to be able to fine tune the
speed so I want a fully variable speed control unit that I would attach
to the power cord, and control the speed from there instead.

The operator's manual states that the fan must not be used with a solid
state speed control device. I understand that to mean that I must not
simply attempt to vary the voltage, i.e. from 120VAC to 90VAC for
example. I understand that this may cause the amperage to rise, and all
sorts of nasty things may occur after that.

I read a little about the problem and I believe that the integrated
speed control unit controls the speed by varying the AC frequency while
maintaining the same voltage, i.e. from 120VAC 60hz to 120VAC 50hz and
so forth. Though I don't actually know.

I sent a request for information on how to do what I want but I got the
standard "don't do it" reply. As if by some magical mysterious way, I'm
going to change my mind. So no luck from the manufacturer.

I've looked at the Air King 9155 model and I believe it's the same as
the Lasko 2155A. Somebody correct me if I'm wrong. I also believe Lasko
doesn't actually manufacture that model, they only sell it. So that
might explain why I got the standard "don't to it" reply from them. I'll
ask Air King next to see if I have better luck with them.

If any of you have experience with this kind of thing, please advise me
on how to proceed. If there's already a device that I can buy and just
plug in, that would be best. If there's some tinkering to do, it would
depend on the depth and complexity of that tinkering.

Actually what would be best is if I found a similar window fan with an
integrated fully variable speed control unit. Alas, the available choice
of window fans pretty much stops at Air King. Though I understand that
there's a slew of window fans that are not made anymore, like the
Vornado for example, so that might be an option. However, my primary
consideration of any window fan remains a fully variable speed control unit.

Thank you

Martin Levac

http://www.laskoproducts.com/fans/mo...l/window1.html

The reason for this is that most electronic speed
control devices produce non-sinusoidal waveforms.
This causes the motors to overheat due to Increased
"iron losses".
Some can stand it, some can't.
Obviously, yours is a "can't"