A sump pump is an essential tool for protecting your basement from flooding and water damage. Unfortunately, sump pumps can sometimes fail, leaving your home vulnerable to water damage. In this blog, we’ll cover the basics of sump pumps, common causes of failure, and how to diagnose, replace, and install a new sump pump. We’ll also reference expert advice from Family Handyman, This Old House, and other trusted sources to ensure you receive accurate and helpful information.

What is a Sump Pump and How Does It Work?

A sump pump is a device designed to remove water that has accumulated in a sump basin, typically located in the basement or crawl space of a home. The pump works by collecting water in the basin and then pumping it away from the home’s foundation, preventing flooding and water damage. There are two main types of sump pumps: submersible pumps, which sit inside the sump basin and are fully submerged in water, and pedestal pumps, which have a motor mounted above the basin (Family Handyman). For more information on sump pumps and their operation, check out HowStuffWorks’ guide on sump pumps.

Common Causes of Sump Pump Failure

Sump pumps can fail for several reasons, including:

  • Power outage: Since most sump pumps rely on electricity to operate, a power outage can cause the pump to stop working. Installing a backup battery-powered pump can help prevent this issue.
  • Clogged or frozen discharge pipe: If the discharge pipe becomes clogged or frozen, water cannot be pumped away from the home, causing the pump to fail. Regularly inspect and clean your discharge pipe to prevent clogs.
  • Improper installation: If your sump pump is not installed correctly, it may not function as intended. Always follow the manufacturer’s instructions or consult with a professional for installation.
  • Mechanical failure: Over time, the pump’s components can wear out or become damaged, leading to failure. Regular maintenance and inspection can help catch these issues before they cause a problem.

For more information on sump pump failures, check out SumpPumpJournal’s guide on the subject.

How to Diagnose a Faulty Sump Pump

If you suspect your sump pump is not functioning correctly, there are a few steps you can take to diagnose the issue:

  1. Check the power supply: Ensure the pump is plugged in and that there are no issues with the electrical supply or circuit breaker.
  2. Test the float switch: The float switch is responsible for activating the pump when the water level rises. Ensure it can move freely and is not obstructed by debris.
  3. Inspect the impeller: The impeller is responsible for moving water through the pump. If it is damaged or clogged, the pump may not function correctly.
  4. Check the discharge pipe: Ensure the discharge pipe is not clogged, frozen, or damaged, preventing water from being pumped away from the home.

When to Replace a Sump Pump

There are a few signs that it may be time to replace your sump pump:

  • Age: Most sump pumps have a lifespan of 7-10 years. If your pump is approaching or has exceeded this age, it may be time to consider a replacement.
  • Frequent cycling: If your sump pump is frequently turning on and off, it may be a sign that it is struggling to keep up with the water flow or that the float switch is malfunctioning.
  • Noisy operation: Excessive noise during operation can indicate that the pump is working harder than it should, or that there are issues with the motor or impeller.
  • Persistent problems: If you’re consistently encountering issues with your sump pump, even after repairs, it may be more cost-effective to replace the pump rather than continue fixing it.

How to Select a Replacement Sump Pump

When choosing a replacement sump pump, consider the following factors:

  • Type of pump: Decide whether a submersible or pedestal pump is the best option for your needs based on your sump basin size and preferences.
  • Horsepower: Select a pump with enough horsepower to handle the water flow in your basement. Consult with a professional if you’re unsure about the appropriate size.
  • Backup system: Consider a pump with a battery backup or dual-pump system to ensure continued operation during power outages.
  • Material: Pumps made from cast iron or stainless steel typically offer better durability and longevity compared to plastic models.

How to Install a Replacement Sump Pump

Installing a replacement sump pump involves the following steps:

  1. Disconnect the old pump: Unplug the pump and disconnect it from the discharge pipe.
  2. Remove the old pump: Carefully lift the old pump out of the sump basin, taking care not to damage the basin or float switch.
  3. Prepare the new pump: Install the new pump’s float switch, check valve, and any other necessary components according to the manufacturer’s instructions.
  4. Lower the new pump into the basin: Carefully lower the new pump into the sump basin, ensuring that it sits level on the basin floor.
  5. Connect the discharge pipe: Attach the discharge pipe to the new pump, ensuring a secure and watertight connection.
  6. Test the new pump: Plug in the pump and test its operation by pouring water into the basin until the float switch activates the pump.

For more detailed instructions on sump pump installation, check outFamily Handyman’s guide on installing a sump pump.


Sump pump failure can be a significant issue for homeowners, but understanding the causes of failure and knowing how to diagnose, replace, and install a new pump can help you protect your home from water damage. Regular maintenance and inspection of your sump pump can also help prolong its lifespan and ensure optimal performance. If you’re unsure about any aspect of sump pump replacement or installation, consider consulting with a professional, such as Reliable Basement Waterproofing, to ensure the job is done correctly and your home remains protected.