Matching switch to motor

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slownsteady

slownsteady

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I want to replace the Hi/Lo switch on my whole-house fan for something that looks a little more modern. The old metal toggle switch still works but it is in an open area and it looks very dated.

Most of the contemporary switches i am finding are meant for ceiling fans. Do I have to find a switch that's rated for the load it is going to pass? The fan is 5.5 amps, the current switch is rated for 10 amps. How much leeway do I have have in this setup? I guess i have the same question for the old 12- hour spring loaded timer that I'll replace too.
 
Do I have to find a switch that's rated for the load it is going to pass? YES
The fan is 5.5 amps, the current switch is rated for 10 amps.
How much leeway do I have have in this setup? No leeway for lesser amperage, but higher amperage allows for more options.
I guess i have the same question for the old 12- hour spring loaded timer that I'll replace too. Same applies for any kind of switch/timer.
Now all we have to do is figure out what you consider "Contemporary".
The first thing that popped into my mind is installing a 3-way light switch, rated for 15amps but, we need to see what's behind that toggle switch.
Could you remove the faceplate and post a pic of the wiring attached to the toggle switch ?
 
Here's pix of the old switch. If I can't find a decent switch at a decent price, I will skip the low speed position and just use an on/off setup with the low line capped and left in the box.

IMAG0629.jpg

IMAG0630.jpg

IMAG0636.jpg
 
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Found this at Home Depot.

Don't really care that it adjusts for daylight savings, and the 7 day timer function may be overkill.

But I like that the timer and switch can be in a single box, and the ratings seem okay. If it's hard to read:
120VAC 60HZ
20A resistive
15A tungsten
16A ballast
1HP motor

My fan is rated at 1/4HP on the faceplate and the circuit is on a 15A breaker, so I think it is okay, but I'm still asking....

IMAG0644.jpg

IMAG0645.jpg
 
slownsteady said:
Here's pix of the old switch. If I can't find a decent switch at a decent price, I will skip the low speed position and just use an on/off setup with the low line capped and left in the box.
Click to expand...

Your present switch looks like 3 position, on, off, on Don't think you will find one that looks like a regular switch.
 
The old switch is hi/off/lo. I don't think we've ever used the lo speed. Like I mentioned earlier, i think I'm just going to bury the low leg in the box.
I found a newer style that i could use, but at $37 for just the switch, and the style was less than modern (the wife wasn't impressed). And then I would still need to replace the old timer.
 
So I hooked up the switch temporarily as a single pole setup, and it works fine. I will go forward with the installation.
But it raised questions that I would like to know for my own education.
There was no indication on the old switch on which wire was the hi leg and which was the lo. And I don't have any schematic on the fan. So I had two choices on which wire to connect to the new switch. When I connected the red wire and switched on the fan, the breaker tripped right away. The black wire worked correctly. The question is - how would I know without trying one? Why did the breaker trip? And how does the fan accomplish two speeds from the wiring setup? Is it both wires supply more voltage to the motor, or a separate path inside the motor for each speed, or something else?

Another piece of the puzzle: the unused red wire carries current only when the fan is on. Since it is not in the switch circuit, it must be returning through the fan??? I guess that I would disconnect that at the fan so that it's a dead wire.
 
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If the switch in the picture is still the same orientation as used and high speed was up then the 2 black wires would be for high speed. The middle terminal is the feed bottom terminal would be high, top terminal (red) would be low.

Yes the unused wire would be back fed from the motor so disconnect at motor or cap in the box. Not sure how you had it wired to pop the breaker.
 
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