Sump Pump Running but Not Pumping (A Quick and Easy Fix)

The sump pump is the last line of defense that can save your basement from flooding waters. But just like any other equipment, it isn’t immune to breaking down or malfunctioning.

One of the common problems that homeowners face with their sump pumps is that they can suddenly stop pumping while running. So, here are the reasons why this can happen:

  • Mechanical defect with the float
  • Faulty check valve
  • Clogged inlet and discharge line
  • Damaged impeller
  • Wrong pipe sizes

Now that you know the possible scenarios that can restrict the functions of your pump, you need to know how to locate and diagnose the problem. So, how do you diagnose it?

Sump Pump Running but Not Pumping

Why Your Sump Pump Is Not Working?

Before you solve the problem, figuring out what’s causing the problem is essential but tricky. Here is a list of possible causes:

Mechanical Defect with Float Switch

When the water level inside the pit rises up, the float switch rises along with it and signals the sump pump to start removing water. However, if the switch is unable to relay any signal, then the pump will not discharge any water.

This can happen due to a few reasons:

  • The switch can be faulty or defective.
  • The position of the pump inside the pit can shift. This can cause the switch to get itself jammed along the edges of the pump.
  • The switch can get stuck by debris present in the sump water or by dangling wires, therefore, unable to rise and activate the pump.

Solution – First, you need to visually inspect the float switch.

  • In the case of faulty equipment, you’re only left with the option- to replace the float switch.
  • If the pump has tilted, then you need to re-adjust it back to vertical alignment. However, before you do that, the sump pit has to be empty first.
  • If the float ball is obstructed by any object, then take it out of the way. After that, try lifting the float with your hand and check if the pump is receiving any signal to activate or not. If it does, then add water to the pit and let it pump.

Damaged Check Valve

The check valve is a crucial component of the drainage system. If your float switch is working properly, then the problem may lie with the valve. It is attached to the discharge pipe. When the water is pumped out by the sump pump, a portion of water always gets held back in the pipe. The valve prevents the backflow of water into the pit.

So, if the valve is damaged or is missing, the water will flow back into the pit and reverse the direction of the impeller.

Solution – To inspect the valve, you must unplug the sump pump before checking. If you notice that your check valve is missing, then you can have it installed. And, if you happen to see cracks or any other signs of damage, then it is best to replace it.

Discharge Line Blockage

As we mentioned earlier, the discharge line is an essential part of the system. In fact, if the water doesn’t flow smoothly through the pipes, the entire system can break down. Sadly, there are a few reasons why the flow can get disrupted.

  • The water that gets collected in your sump pit during the rainy season has a high concentration of debris and gravel in it. They can cause the discharge pipe to get clogged. As a result, the flow of water will get restricted, and the pump will not be able to empty the pit.
  • Similar to the clogging of the discharge pipe, the debris can also block the inlet line as well.
  • During the coldest of months of winter, it is quite common for the water in the pit to freeze. If the pump takes in any icy water, it can freeze both the inlet and pipe and the pump will stop pumping.

Solution – To look for blockages, then:

  • First of all, check the outer end of the discharge pipe for any debris. If you find any, you can remove them with your hand by using a pair of rubber gloves or a screwdriver if you find it hard to remove them.
  • If the discharge line is clear, then take a look at the inlet line. Remove any visible clogs and clean the pipe properly.
  • In the case of ice, you can thaw it by pouring hot water into the line.

To make sure that the pipes are clear of any debris, pour water through the disconnected lines. Remember, while you are inspecting, the pump should be turned off.

Malfunctioning Impeller

The impeller of the sump pumps is the heart of the entire operation. It draws the water into the pump and directs it outside through tubes. Usually, the pumps have a screen in front of the impeller to prevent the debris from jamming the blades.

However, sometimes tiny dirt particles make their way through the screen and get lodged onto the blades. If this continues for a period of time, the impeller will begin to malfunction. The blades will stop spinning, and the pump cannot pump any more water.

Solution – To clean the impeller, you need to dismantle the pump out of the pit. Then, you need to take off its casing and reach out for the screen and then the impeller.

While removing the casing, if you notice that the impeller has become unhinged or has fallen off, you can re-thread it back. However, if there are any damages to the impeller, then you will need to replace it.

Wrong Pipe Size

One of the common mistakes made during installation is getting the wrong pipe size. If the diameter discharge pipe is too small, then it will add strain onto the pump and reduce its efficiency.

SolutionEvery sump pump model has its own set of specifications about the size of the pipe it needs. If you believe that the pipe isn’t of the right size, then re-measure its diameter. If it is small, then you can replace it with the right size.

Is It Time for A Replacement?

Age can be one of the major reasons behind the malfunctioning of your pump. Normally, a pump has a life expectancy of 10 years. However, there are some that can run on for 15-20 years.

However, after a rigorous amount of wear and tear, the pump can get overwhelmed and eventually give out. So, after ticking off all the other possible reasons, if your pump is still not working, then it’s time for a new one.

Steps to Maintain the Pump`

Regularly maintaining your sump pump can increase its life span and also improve its efficiency. The frequency of how often you clean the pump and the pit depends on how much it is being used. Nevertheless, it’s a good habit to clean it every 6 to 9 months.

Here’s the step-by-step procedure:

  1. Before you begin, ensure that the sump pump is switched off and then unplug it.
  2. Disconnect the discharge tube and then remove the pump from the sump pit.
  3. Once you have taken the pump out, jump inside the pit and inspect the switch. Look for any obstacle in its path.
  4. While you are in there, clean the sump pit and the check valve by using a pair of gloves and a rag. Remove the dirt, gravel, and sludge from the bottom of the basin and then wipe down the walls as well.
  5. After you are done, get out of the pit. Now, you can focus on the pump. Clean the outer sides of the pump. If there is rust on the surface, then take a look at the instruction manual. See if you can apply oil or any other products to get rid of it.
  6. Next, clean the inlet line and then remove the casing of the pump. Usually, there is a lid underneath that allows you to clean the insides.
  7. Before you inspect the impeller, remove the screen covering it, and then wash it.
  8. Later, take the impeller out. Look for any signs of damage or clog on it. Clean out the blades.
  9. After all the above tasks have been done, reassemble the parts back together and then re-install the pump into the pit. Reconnect the discharge line and then switch on the pump.
  10. Pour in clean water until the float bulb rises, see if the pump starts pumping water out.

How Do You Know That Your sump Pump Has Stopped Pumping?

Unless you are constantly taking a peek into your sump pit, it is difficult to find out whether your pump is pumping water out or not. This can become a nightmare for you, especially in the middle of a storm, when the water levels will continue rising and flood your basement, without your knowledge.

So, to help you monitor the status of your pump- you can install a sensor onto the float switch that will notify you by beeping when the water level is beyond the danger line.

Final Words

Once you know your way around the sump pump, it’s pretty easy to resolve any clog-related issues. You can do so without relying on any professional help. All you need to do is simply follow the steps, and most of your problems can be solved.

However, no amount of poking, prodding, magic, or alchemy can revive a pump that is either dead or about to die. So, the blueprint goes something like this- try to find and fix. If it doesn’t work- take the hit and get a sump pump.

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