How to Install a Condensate Float Switch

Condensation builds in the drain pan of an air conditioning unit as the unit cools incoming air. A condensate switch turns on a pump when condensation builds to a level that it could flow out of the pan and onto the surrounding area. When a condensate switch fails, condensation will begin to overflow the sides of the condensate pan. The overflowing condensation will damage wood supporting the AC unit and create an environment that promotes the growth of mold and mildew.

Things You'll Need

  • Wire cutter

  • Wire stripper

  • 2 wire nuts

Step 1

Flip the breaker supplying power to the air conditioning unit to the "Off" position to disconnect power to the unit.

Step 2

Turn the two thumb screws located on the backside of the condensate float switch counterclockwise to increase the mounting slot gap.

Step 3

Slide the opened slot over one flange of the condensate pan resting below the AC unit with the body of the switch sitting inside the condensate pan. Push the switch down until the bottom of the switch sits firmly on the bottom of the condensate pan. Turn the two thumbs screws clockwise to lock the switch in place.

Step 4

Cut the red "R" terminal wire running the thermostat with a pair of wire cutters. Strip 1/2 inch of insulation from each end of the cut terminal wire and the end of each float switch wire with a pair of wire strippers. Twist one end of each float switch wire to one of the exposed section of the cut "R" terminal wire. Secure the wires by twisting one wire nut onto each pair of wires.

Step 5

Flip the breaker to the "On" position.

References & Resources