How To Replace A Central Air Condensate Pump

If you have a central air system that has stopped cooling, or you find puddles of water around the unit, check the condensate pump. A condensate pump is an important safety component as it removes condensation through a pipe, and it will shut off before the water damages the unit.

Replacing a condensate pump doesn't require advanced HVAC skills. Here are tips to replace an HVAC condensate pump.

Prepare to Work

For this project, you need:

  • work gloves
  • bleach
  • screwdriver
  • wrenches
  • wet vacuum
  • replacement rubber hose (optional)
  • condensate pump

Let the unit run several cycles to remove oil. Before you remove the pump, try replacing the breaker switch that controls the unit. Sometimes, replacing the switch could fix the problem.

A breaker switch commonly slides off, or if it has screws attached you can remove with a screwdriver. Turn the power back on to test the unit. If the unit still doesn't work, proceed to replace the pump. Shut off power from the breaker box, and turn the thermostat down to the lowest setting.

Remove the Old Pump

The condensate pump is located inside the service panel on the outside unit. Use the screwdriver to detach the screws from the service panel.

Look for the pump near the coils, or somewhere next to the unit. Condensate pumps have two sets of wires. A low-voltage wire set shuts off power when the drip pan is full, and the high-voltage wire set operates the motor.

Disconnect the drain hoses or tubes attached to the pump. You may want to take a picture of the wiring to use as a guide for connecting the new pump. Unplug high-voltage wiring.

Remove the wiring from the low-voltage wires by untwisting the wire nuts. Loosen the screws on the pump to detach it, taking care not to spill the water in it.

Install the New Pump

Replace damaged hoses or tubes. If the hoses or tubes are still good, clean them with bleach and warm water, and let them dry.

While the panel is off, check the drip pan attached to the coils. Depress the clips, or remove the screws to slide the pan out. Avoid touching the water in drip pans with your hands, because it could be contaminated. Use a wet vacuum to remove water.

Insert the new pump in place of the old one, connecting the wires and securing the connections with wire nuts. Reinstall the panel.

Restore power, and test the replacement pump. If you don't trust your skill, or the unit fails, contact a heating and air conditioning service.