Fangrui Product Details Hvac Float Switch Function: Ss2 Water Level Switch Is Used In Hvac Systems To Detect Condensation Water Overflow; It Detects Blockage Of Air Conditioning Condensate Water Drain Pipe And Shuts Down The System To Prevent Overflowing Water From Damaging Floors, Walls, And Ceilings Working Principle: The Float Switch Hvac Can Be Connected To A Vcc Or Thermostat Line; It Is An Nc Type (normally Closed) Switch: When No Water Overflows, The Float Stays At The Bottom Of The Switch, The Switch Closes The Loop And Outputs An On Signal; When The Water Overflows, The Buoyancy Of The Float Rises, The Trigger Switch Turns On, And The Output Off Signal Turns Off Specifications: Switch Type Nc ( Normally Closed) , Material Pvc, Operating Temperature -20 - + 80 Wire Length 5.8ft, Switching Voltage Max; 200vdc; Switching Current Max; 1 A Contact Rating Maximum 10w Easy To Install: This Float Switch Hvac Is Easy To Install, All You Need To Do Is Install The 3/ 4 Adapter That Comes With The Ac Float Switch On The Auxiliar