Honeywell S688A1007 Sail Switch with 5 in. Wide Sail
Originally Posted by python01
Can I get them at most home improvement stores?
Probably not. Try HVAC supply houses in your area. If you sound business-like they might sell it to you for the wholesale price.
What would be proper name for this type of switch?
or you can make your own with a $2 Microswitch from Hosfelt.com or Radio Shack.
If you use this switch to control the 24vac instead of the 120v, the danger level of this project is about the same as having a meteorite hit the ground 10' in front of you.
I used homebrew logic circuitry to do this function, but my circuit must be unplugged if the AC is turned on because that puts ~2x the rated voltage into my circuit through the blower motor.
It's not widely known but it is hinted at in the humidifier installation instructions, that when you put 120v into one winding of your blower motor to select the speed, the other windings are putting out all different voltages, some of which are quite a bit higher than 120v. This motor acts like a transformer with multiple taps on the windings.