Your home's sump pump is an extremely important part of your plumbing system and serves to protect your foundation and basement from flooding during times of excessive rainfall. A malfunctioning sump pump can pose a number of potential issues for your home, including water damage and mold and mildew growth, which are both expensive and complicated to repair. Understanding the warning signs associated with a failing sump pump can help you have it repaired before it fails.
Sump pumps are usually submerged in water, which opens them up to mold growth if they are not properly serviced over time. If you notice that there is a foul, earthy smell in your basement near where your sump pump is installed, it is likely that your sump pump is in dire need of cleaning. Besides the smell and health hazard that mold can pose, mold growth can actually clog up your sump pump and prevent it from removing water from your foundation, increasing the likelihood of flooding.
Sump pumps are by no means quiet appliances, but they should not be overwhelmingly noticeable when they turn on. If your sump pump makes excessive noises that overpower the everyday noise of your home, or if your sump pump is making irregular noises, such as knocking, grinding, or bumping sounds, you should contact a plumbing professional to take a look at your pump and ensure that it is in good working order. Most of the time, loud sump pump operation can be attributed to worn components that aren't functioning properly, creating excessive friction and contributing to even more wear and tear on your pump. This greatly increases the risk of an actual pump failure, and shouldn't be left alone for long.
If the float of your sump pump becomes stuck, it will not function as water levels rise in your foundation and therefore will not remove water from your home. The easiest way to see if the float of your sump pump is floating freely or not is to pour a pitcher or water into the actual sump reservoir. The pump should activate once the water hits a certain level, and remove all of the water from the pit, but if it does not then the float has likely become stuck in place. This can happen for a number of reasons, but it can be hard to determine on your own: your best course of action is to call a plumber as soon as you can.