How To Tell If A Condensate Pump Is Working (Do This!)

Ossiana Tepfenhart
by Ossiana Tepfenhart
The condensate pump on your air conditioner is a key part of its function, and it’s important to address it right away if it goes bad. You can tell that your condensate pump is going bad if you discover clogs or mold inside of it. Whether it be identifying the problem or reaching a solution, follow along as we explore what you should do when your AC’s condensate pump goes bad.

If you recently noticed a strange pool of water near your HVAC unit, then you probably have been thinking about checking out the condensate pump. Condensate pumps are a vital part of most air conditioning units. This is doubly true if you live in a humid environment prone to lots of moisture. It’s normal to wonder if your pump’s actually working. So, how can you tell if it is?

After ascertaining that your pump has power, check both of the pump’s pipes for mold clogs. After cleaning out any clogs you see, pour some water into the pump’s source and turn it on. If the pump is pushing water out the other end, then your pump is working. If not, then you may need a new condensate pump.

A condensate pump that doesn’t work isn’t going to do much for your HVAC system. That’s why knowing how to troubleshoot it matters so darn much. Let’s talk about it, shall we?

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What Does A Condensate Pump Do?

Most people do not know what a condensate pump is, or what it’s supposed to do. A condensate pump is meant to pump water that’s produced from your HVAC system into a drain. This helps remove rust and condensation, which in turn, helps prevent damage. They’re nifty like that.

Your condensate pump generally won’t be part of your AC unit. Rather, it’ll be off to the side and will resemble a box that has a smaller box sitting on the bottom of the first box. Your pump will be plugged into an outlet and will have two different plumbing lines running in and out of it. One of the lines will be a large thick PVC pipe, the other will be thin and wiry.

Are There Any Signs That Suggest Your Condensate Pump Is Broken?

While there are many parts of your air conditioning unit that could display their malfunctions pretty prominently, condensate pumps are not one of those parts. The biggest symptom that suggests something might have gone awry is a sudden pooling of water in your basement or around your air conditioner.

If your condensate pump is making strange noises or if it’s starting to act laggy, then you might have a pump that’s in need of servicing. In many cases, this could be a sign that you have mold or algae buildup in your hosing. So, don’t jump to conclusions until you’ve troubleshot your pump.

Testing Your Condensate Pump

Once you’ve figured out which item in your home is the condensate pump, it’s time to look at it more closely. To test your condensate pump, follow the directions below:

  • Start by checking to see if your pump is plugged in and turned on. If it’s not, plug it in and make sure it’s capable of turning on.
  • Unhook both plumbing tubes and inspect them for mold growth. If they have mold, use a brush to remove the mold. This will ensure that your piping is capable of transporting the water from one side of the pump to the other. Make sure that both plumbing lines can be securely attached to the pump, and attach them if you haven’t already.
  • More extreme clogs can be taken care of through a wet/dry vacuum. Remove the lines and create a suction by wrapping a towel around them. Turn on the vacuum, and the clogs should be removed. Reconnect the piping after they’ve been suctioned.
  • Remove the two drainage lines from the pump, then set a brick (or other weight) on a bucket. Place the condensate pump on top, making sure it doesn’t budge easily.
  • Pour water into the hole for the large PVC pipe. You should hear the pump’s trigger turn on, making the machine hum softly. After a short amount of time, you should see water being forced out the other end of the condensate pump. If you don’t see that, your pump is broken.

What Should You Do If Your Condensate Pump Isn’t Broken?

Once you’ve ruled out the possibility of your pump’s lines being too cloggy to work, it’s safe to say that your condensate pump is busted. Unfortunately, there’s not much you can do to make this pump work once that’s the case. In order to have a working HVAC unit in an area that’s at risk of black mold, you will need to have it replaced.

How Can You Tell If Mold Is Clogging Up Your Condensate Pump Lines?

In many cases, people end up believing that they have a bad condensate pump when they really just have a mold problem with the pump’s lines. Thankfully, troubleshooting the condensate pump usually clears up the issue. With that said, there are several common signs that you may have a mold problem:

  • You had to clean out mold in the piping by hand, or through the wet/dry vacuum. If you notice green or brown buildup at the bottom of your wet vac, you have a mold issue.
  • There is visible mold growth around the pump. You may need to fix this issue ASAP. If it’s gotten to the point where you can see mold outside of the machine, you have a serious problem impeding its function inside.
  • You notice water pooling around your unit, but the condensate pump itself was totally fine. If this is the case, switch the lines in order to make your unit run smoothly.

Do You Need To Have A Condensate Pump?

Believe it or not, a condensate pump isn’t always necessary. If you have an air conditioning system that has enough of a gravity pull to be able to properly drain condensation, then a condenser pump isn’t a must-have. Condenser pumps are only really necessary for setups that don’t have a built-in drainage system.

With that said, if you notice a lot of water pooling at the bottom of your air conditioner, you probably should invest in a pump. On a similar note, a good rule of thumb to follow is to assume that you have to replace your pump if you have one. Otherwise, you might end up with mold in your AC unit or water damage to your system.

How Much Does Condensate Pump Replacement Cost?

Condensate pumps are not exactly expensive, but they are going to have to be replaced. An actual condensate pump will only cost $45 to buy. If you want to get the pump professionally installed, you should expect to pay a total of $100 to $150. So, as far as HVAC repairs go, this is pretty affordable. It’s way better than replacing a bad blower motor!

Why Would You Install A Condensate Pump In Your Home?

Along with preventing mold growth, many people choose to install a condensate pump in their homes for other reasons. The most common reason why deals with all the plumbing. Believe it or not, adding a condensate pump in your home can make your home a little more aesthetically pleasing.

The reason for this is fairly simple. Condensate pumps help organize all the piping and wiring. Rather than letting all those wires run loose in a basement, people would rather have them run through the pump. Besides, condensate pumps help your HVAC system run a bit more efficiently in some cases. So, even if you’re not big into aesthetics, it’s often a win-win.

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Related Questions

How long should a condensate pump last?

Believe it or not, condensate pumps are fairly durable considering their low price tag. On average, a pump should be able to last for at least two to three years. Some particularly well-built condensate pumps can last for as long as five years before they need to be replaced.In order to ensure that your pump lasts as long as possible, make sure to clean out the hosing frequently and to prevent mold from getting in the way of things. With that said, condensate pumps require minimal upkeep. So, you won’t have to fuss too much over them.


How big of a condensate pump do I need for my home?

Most homes do not need to have an exceedingly powerful condensate pump, even if they live in a humid area. A typical home will need to have a 1/30 horsepower condensate pump at most. Most smaller homes will need an even smaller pump, with 1/50 horsepower being quite sufficient to handle most needs.Like with most other HVAC issues, if you aren’t sure what you need, it’s best to ask a professional. That way, you can make sure that you get the right specs for your home’s dimensions.


Can I put bleach in a condensate pump?

If you have algae and mold growing inside your condensate pump, it’s possible to clean it out by flushing your system with a bleach solution. To do this, mix a dilute solution of bleach and water and pour it into your reservoir. Let it sit for a moment, and then turn on your pump until it starts moving the bleach through your system.Place the “exhaust” pipe into a bucket in order to store the stuff that comes out of your system.

Ossiana Tepfenhart
Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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