Little Giant Sump Pump 6-CIA Troubleshooting

Little Giant Sump Pump 6-CIA Troubleshooting

Little Giant 6-CIA is a reliable sump pump that helps you empty a small spa, pool, and so on. But over time, it starts malfunctioning like the pump won’t shut off or the unit fails to discharge water. 

And this guide on Little Giant Sump Pump 6-CIA Troubleshooting will help you resolve those common sump pump issues. 

Without further ado, let’s dive in. 

Table of Contents

Little Giant Sump Pump 6 CIA Troubleshooting [4 Problems & Solutions]

This chapter will take you through 4 common problems of this sump pump and their solutions as well. 

1. Pump Won’t Shut Off

Your Little Giant Sump Pump 6-CIA won’t shut off if there is a problem associated with: 

  • Diaphragm switch is at fault 
  • Weak or hardened rubber diaphragm 
  • Plugged vent tube 
  • Dirt or sediment lodged between retainer ring and rubber diaphragm 
  • Pump is air locked 
  • Liquid inflow matches pump capacity
  • Defective switch 
  • Loose connection in level control wiring 

How To Fix: 

Before troubleshooting automatic control, inspect the unit to see whether it comes on manual control or not. 

Regarding this, create a slight vacuum on the breather tube, which is located near the plug. Then, close the tube with your thumb and plug the unit into the wall outlet. If the pump comes on, move forward to check the diaphragm switch. 

If the pump doesn’t work, I bet there is a problem in the pump or power supply. And here is the tutorial that will help you test the diaphragm switch: 

Don’t hesitate to replace the diaphragm switch if it’s at fault. 

Secondly, inspect the rubber diaphragm and ensure it doesn’t get hardened. If it’s weak, replace the rubber diaphragm with a new one. 

Thirdly, check the vent tube and ensure there is no restriction. If yes, release the obstructions from the vent tube. 

Fourthly, take a look at the rubber diaphragm to check whether there is debris or sediment lodged between retainer ring and rubber diaphragm. Clean the rubber diaphragm if required. 

In the event of pump airlock, the pump fails to move water from the sump pit. To fix airlock issue, go along with the following steps: 

  • Shut off power to the unit for approximately 1 minute. Then, restart the unit. 
  • Repeat the shutting off and restarting of the unit several times to clear air from the pump. 
  • If the unit includes a check valve, you must drill a 3/16” hole in the discharge pipe approximately 2” above discharge connections. The hole should be located below the floor line between the pump discharge and the check valve. It will allow the air to be released, allowing the water to reach the impeller. 

I highly recommend you to watch this tutorial to master on preventing airlock on Little Giant 6 Series:

 Apart from these, the pump won’t shut off if the liquid inflow matches the pump capacity. In this case, you must install a larger pump to handle this situation. 

Nonetheless, a defective switch is another caveat that prevents the unit from shutting off. You can easily determine whether the switch is at fault or not by testing it electrically. 

To test the switch, disconnect the switch and measure the electric resistance of the switch using a multimeter. The resistance reading should be closed to zero on an open circuit test. 

If the resistance reading goes out of specification, understand the switch is at fault. Replacing the switch will be a simple fix to this issue. 

Finally, check the control wiring for loose connection and tighten up the wiring if needed. 

2. Pump Runs But Doesn’t Discharge Liquid

Your Little Giant 6-CIA runs but it fails to move water from the sump pit! If this is the issue you are going through, I bet the following culprits are responsible for this.

  • Check valve installed backwards
  • Check valve stuck or clogged 
  • Lift too high for pump
  • Inlet to impeller gets plugged 
  • Pump is air locked 

How To Fix: 

To begin with, inspect the check valve for proper installation. If you install it incorrectly, your sump pump won’t move liquid from the sump. Just check the flow indicating arrow on the check valve body to verify you installed it properly. 

In addition, a clogged check valve is responsible for the pump to not discharge water while it’s in operating state. I recommend you to remove the check valve and inspect it for proper operation. 

Next, make sure the lift for the pump is not too high. The best bait is to check the rating table and size up the lift height according to that for proper pump operation. 

Furthermore, a clogged or restricted impeller is also a culprit that stops the pump from pumping water. In such a case, cleaning the impeller will be a simple fix. To clean the impeller: 

  • Disconnect the pump from the electric connection and pull it out.
  • Detach the bottom cover from the unit by using a screwdriver. In this case, pry up the screwdriver gently and take off the cover. 
  • Now, clean the impeller area with a brush and wash the area with clean water. 
  • Once you clean the impeller, replace the bottom grate into its place and restore the power to the unit. 

And last not the least, pump air lock issues can prevent the unit from pumping water out of the sump though the unit is running. Fortunately, I already mentioned the corrective actions you need to take to prevent the airlock. So, follow the instructions and resolve the airlock problem. 

3. Pump Doesn’t Deliver Rated Capacity

The Little Giant 6-CIA pumps water out of the sump but not as per its rated capacity? If yes, go for troubleshooting the following culprits: 

  • Lift is too high for the pump
  • Low voltage 
  • Impeller or the discharge pipe gets clogged
  • Worn out impeller 

How To Fix: 

First off, check the rated capacity of the pump and set the lift height according to that. I recommend you take a look at the rated pump performance to get a better idea. 

Secondly, you can’t expect your desired pumping performance out of the sump pump if it receives insufficient power supply. It’s recommended to check for proper supply voltage to ensure it corresponds to nameplate voltage. 

If it doesn’t receive sufficient voltage to activate the unit, call a certified electrician to wire your sump pump properly. Also, make sure you plug the unit into a dedicated and properly grounded outlet. 

Thirdly, you will get a slower flow rate if the impeller or the discharge pipe gets restricted by debris. In the previous chapter, I described the cleaning method of the impeller. Once you clean the impeller, check the discharge pipe and release the restrictions from the pipe. 

And lastly, replace the impeller if it becomes rusty or gets worn out. 

4. Pump Cycles Continually

Your sump pump cycles too frequently due to one of the following reasons: 

  • No check valve installed
  • Check valve leaking
  • Sump pit is too small for inflow

How To Fix: 

First, ensure there is a check valve installed in the discharge line. If not, install a check valve in the discharge pipe which will prevent the liquid from coming back into the sump. 

Second, inspect the check valve for proper operation and ensure it’s not leaking. If needed, replace the check valve with a new one. 

And thirdly, install a large sump pit if the existing one is too small for inflow. 


That’s it! I covered all the common problems you might encounter with your Little Giant Sump Pump 6-CIA. Just follow the troubleshooting steps and resolve a specific sump pump issue. 

Or, you can hire a certified plumber if the problem you face with your sump pump seems a bit complex. 

Happy Plumbing!

Read Also:

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *