How does a float switch work?

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How does a float switch work?

Author: sum (FL)

I was looking at an HVAC floats switch and am wondering how it works?

I mean, I know how it works in a sense that if there is fluid in the reservoir (most likely caused by a blockage in the condensate line) the float switch will be activated by the float rising in position, and the electrical is disconnected and the AC is turned off to prevent flooding.

What I don't get is how does it really disconnect the two wires. I am looking at the float itself it is a donut shape made of some plastic material, it sits on top of a metallic "C" clip at the bottom. When water is present this plastic donut rises. When it rises how does it disconnect the two conductors inside the switch?

Re: How does a float switch work?
Author: steve (CA) There's a magnetic reed switch sealed inside and a magnet inside the float.
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