If the air handler unit for your home is in a basement or crawl space, you likely have a condensate pump to help remove condensation from the system. Systems installed higher up in the home, such as in the attic or a utility closet on the main level, typically don't require one of these units. In these cases, gravity is sufficient to allow condensate to drain away.
However, condensate pumps are vital for all other systems. Since your home's main drain line will be above your basement or crawl space floor, the pump is necessary to ensure condensate from your air conditioner system can safely leave your home. Without this pump, water would eventually back up through the drain line, creating a mess on the floor or even damaging your air conditioner.
How Does Your Condensate Pump Work?
Air conditioning condensate pumps are relatively straightforward devices. If you stand near your indoor air-handling unit, you should see a small box on the floor with an inlet and outlet pipe. In most cases, the inlet will use a PVC pipe that originates with your air handler unit, and the outlet will be a clear plastic tube. If your home has a high-efficiency furnace, it will use the same condensate pump.
While condensate pumps are critical to the proper operation of your air conditioner, they're also very simple devices. The lower portion of the unit consists of a submersible pump, float switch, and plastic basin. As the plastic bin fills with water, the float switch rises and triggers the pump. The upper portion of the housing contains the pump motor and electrical side of the system.
What Can Go Wrong With Your Pump?
Since condensate pumps are such simple devices, only a handful of issues typically arise. Most failures involve either the pump itself or the check valve that prevents water from flowing back into the basin. The float switch can also become gummed with debris, stopping it from moving freely and triggering the pump to start working.
Water backing up into the air handler cabinet can cause serious damage, so air conditioning systems always include a condensate safety switch. With a faulty pump, water will eventually fill the inlet pipe, trigger the safety switch, and cause your air conditioner to shut off. If your system stops working and you see water on the floor or a filled condensate line, you know you have a problem.
When Should You Call a Professional?
Three problems can trigger your air conditioner's overflow switch:
- A faulty condensate pump
- A clogged condensate line
- A faulty switch
All three issues are relatively straightforward to solve, but narrowing in on the specific problem can require some expertise. You can always start by cleaning your condensate lines. However, if this doesn't resolve the issue, it's best to contact a professional to determine if the problem lies with your condensate pump, safety switch, or some other part of your system.
For more information on air conditioning repair, contact a professional near you.