Last Updated on July 10, 2023
Submersible pump systems require one essential component: The Float Switch. This handy device automatically regulates water levels in sumps and tanks, saving time and effort.
And the best part? You won’t have to manually turn your pump on and off whenever the water level changes. But how to connect a float switch to the submersible pump?
To connect a float switch to a submersible pump, identify the electrical components of your submersible pump and float switch. Then mount the float switch at the desired level in the water tank. After that, strip the cable insulation and connect it to the pump and float switch.
Today, we will discuss how to wire a float switch to your submersible pump. Also, we’ll answer some of the most common questions about float switches, like how they work and which type is best for sump pumps.
How to Connect Float Switch to Submersible Pump: Step-by-Step Guide
Connecting a float switch is essential if you want to optimize your submersible pump’s performance. Follow these steps to connect your submersible pump to a float switch:
- STEP 1. Ensure safety:
- STEP 2. Identify the Electrical Components:
- STEP 3. Mount the Float Switch:
- STEP 4. Adjust the Float Switch (if needed):
- STEP 5. Prepare the Power Cable:
- STEP 6. Make the Electrical Connections:
- STEP 7. Connect the Power Supply:
- STEP 8. Test the Setup:
- STEP 9. Fine-Tune the Float Switch Position (if needed):
Gather the Necessary Materials:
- Float switch (normally open pump-down type)
- Extension cord
- Power cable for the pump
- Metal bracket and hose clamp (for installation)
- Cable weight or PVC pipe (for adjusting the float switch)
- Tools (screwdriver, wire strippers, pliers, etc.)
STEP 1. Ensure safety:
First, ensure you’re safe by disconnecting the power supply and avoiding wet conditions. Stay safe and take precautions before starting any electrical work.
To ensure your safety, follow these steps:
- Disconnect the power supply: Before starting any electrical work, always disconnect the power supply. This will prevent electrical shock and ensure your safety.
- Avoid wet conditions: Wet hands or wet conditions can increase the risk of electrical shock. Make sure to work in a dry environment and avoid working with wet hands.
STEP 2. Identify the Electrical Components:
It’s time to identify the electrical components involved in your project. First, locate the three-phase wires on your submersible pump. These wires are usually labeled L1, L2, and L3.
The L1 wire is typically the black wire, the L2 wire is usually red, and the L3 wire is typically blue. Next, identify the three wires on your float switch. These wires are typically labeled ‘pump’ or ‘motor,’ ‘power,’ and ‘ground.’
The ‘pump’ or ‘motor’ wire is usually the black wire, the ‘power’ wire is typically the white wire, and the ‘ground’ wire is usually green or bare. Remember that the wire colors may vary depending on the manufacturer, so consult the manual if you’re unsure.
STEP 3. Mount the Float Switch:
Securely attach the metal bracket and hose clamp to hold the float switch in place within your water tank or well, ensuring that it is located in the appropriate position to monitor the water level effectively.
The float switch should be mounted at a height that will trigger the pump to turn on when the water level is low enough to require pumping. This height will vary depending on the specific pump and tank or well setup, so consult the manufacturer’s instructions or a professional if you are unsure.
Once the bracket and clamp are in place, carefully position the float switch to move freely up and down. The switch should not touch the sides or bottom of the tank or well, as this can interfere with its function.
Use the table below as a guide for mounting the float switch at the appropriate height for common submersible pump setups.
| Pump Type | Distance from Bottom of Tank or Well |
| Single-phase submersible pump | 6-8 inches |
| Three-phase submersible pump | 8-12 inches |
| Constant pressure submersible pump | Follow manufacturer’s instructions |
STEP 4. Adjust the Float Switch (if needed):
To fine-tune the activation and deactivation points of the float switch, it may be helpful to attach a weight or PVC pipe to the switch and adjust its position accordingly. This will allow you to customize the water level at which the pump turns on and off, ensuring that it operates optimally for your specific needs.
To adjust the float switch, move the weight or PVC pipe up or down until it reaches the desired water level. Once you’ve found the perfect spot, secure the weight or PVC pipe and test the pump to ensure that it turns on and off at the correct water level.
STEP 5. Prepare the Power Cable:
After snipping off the plug, strip the insulation from the wires to reveal a small section of bare wire for the pump’s power cable. This step is crucial to ensure a proper connection between the float switch and the submersible pump.
The power cable typically has three wires: a black wire, a white wire, and a green or bare wire. There’s a black wire for hot, a white wire for neutral, and a green wire for ground.
To prepare the power cable, you need to connect the wires to the float switch and submersible pump. The connections may vary depending on the specific model and brand of the float switch and submersible pump.
Refer to the manufacturer’s instructions to ensure proper connection. To make it easier, you can use a table to keep track of the wires and their corresponding connections. Here is an example of a table you can use:
| Wire Color | Function |
| Black | Hot |
| White | Neutral |
| Green/Bare | Ground |
STEP 6. Make the Electrical Connections:
Now it’s time to wire up your system and get your pump running smoothly. Let’s dive into making the electrical connections. Follow these steps to connect your float switch to your submersible pump:
- Connect the ‘pump’ or ‘motor’ wire from the float switch to the L1 wire on the submersible pump. This wire is usually red or black and is responsible for powering the motor that runs the pump. Use a wire nut or other suitable connector to secure the connection.
- Connect the ‘power’ wire from the float switch to the L2 wire on the submersible pump. This wire is usually white or yellow and is responsible for powering the pump. It’s important to keep the ‘pump’ and ‘power’ wires separate to prevent electrical issues.
- Connect the ‘ground’ wire from the float switch to the L3 wire on the submersible pump. This wire is usually green or bare and is responsible for grounding the pump to prevent electrical shocks.
STEP 7. Connect the Power Supply:
Once plugged into a GFCI outlet, the power supply hums with energy as it’s connected to the heart of the pumping system.
The next step is to connect the power supply to the float switch, following the manufacturer’s instructions. This is a crucial step in ensuring that the submersible pump operates effectively and efficiently.
To avoid any mishaps, make sure that the power supply is securely connected to the float switch. Double-check all electrical connections and ensure they’re tight and free from damage or corrosion.
Once you’ve connected the power supply, you can turn on the submersible pump and watch it do its job. You’ve successfully connected the float switch to the submersible pump, and now you can enjoy the benefits of a properly functioning pumping system.
STEP 8. Test the Setup:
You’re ready to splash as you turn on the power and watch the water flow through the system, confirming that everything is in working order. Follow these steps to ensure a successful test of your setup:
- Check the water level in the tank or well to make sure it’s at the appropriate level for the float switch to engage.
- Listen for any unusual noises or vibrations coming from the pump or motor.
- Observe the operation of the float switch, ensuring that it activates the pump when it’s up and deactivates it when it’s down.
- Measure the water flow rate to make sure it’s consistent with the specifications of the pump.
- Check for leaks or signs of water damage around the pump or piping.
STEP 9. Fine-Tune the Float Switch Position (if needed):
To get the perfect water level for your system, adjust the weight or PVC pipe on the float switch until the pump activates or deactivates at the desired level. This will ensure a smooth flow of water and prevent damage to the pump or system.
It’s important to repeat the testing process to verify that the adjustments have been successful. If the pump still isn’t activating or deactivating at the desired water levels, fine-tune the float switch position until you achieve the desired results.
How does a float switch work on a submersible pump?
The float switch on a submersible pump is a crucial component that ensures the proper functioning of the pump. It works by detecting the liquid level and automatically turning the pump on and off accordingly.
But how does it know when to switch? The float switch is designed with a hollow float that moves up and down with the liquid level. As the liquid level rises, the float also rises, and when it reaches a predetermined level, it triggers the switch to turn on the submersible pump.
When the liquid level drops, the float also drops, and when it reaches another predetermined level, the switch turns off the submersible pump. This process continues automatically, ensuring that the liquid level in the tank is maintained at the desired level.
What type of float switch is best for a sump pump?
If you want to ensure optimal performance for your sump pump, consider using a vertical action float switch. This type of switch is the best option for sump pumps because they’re highly efficient and cost-effective. Here are some reasons why vertical action float switches are the best choice for your sump pump:
- They’re more reliable than other types of switches because they aren’t affected by the debris that can accumulate in the sump pit.
- They’re easy to install and maintain, which means you can save money on installation costs and repairs.
- They’re durable and long-lasting, so you won’t have to replace them as often as other types of switches.
- They’re highly responsive to changes in water level, so you can be sure that your sump pump will turn on and off at the right times to prevent flooding in your basement.
Is a float switch supposed to have water in it?
The water inside a float switch is like a fish out of water it’s not supposed to happen. Float switches are designed to detect the water level in a tank or sump pit and then activate or deactivate a pump accordingly.
This means that the switch must be able to move freely up and down with changes in water level. If water gets inside the switch, it can interfere with its movement and cause it to malfunction.
What happens if a float switch fails on a submersible pump?
Without a properly functioning float switch, the pump will continue running even when no water is left to pump, causing it to overheat and potentially catch fire.
Meanwhile, the lack of a functioning switch means the pump won’t shut off if the water level rises too high, leading to a flooded basement and potentially thousands of dollars in damages.
To understand the impact of a failed float switch, consider the following table:
| Problem | Cause | Effect |
| Float switch failure | Electrical or mechanical malfunction | Pump runs continuously, overheats, and potentially catches fire |
| Lack of shut off | No functioning float switch | Basement floods and causes significant damage |
Why is my float switch not floating on a submersible pump?
If your float switch is not floating, it could be due to several reasons. Firstly, the float switch might be tangled or stuck, but easily fixed by tapping or squishing it with a broom handle.
However, if this doesn’t work, it might be due to an electrical issue. The sump pump is plugged into the back of some float switches and then plugged into the wall outlet. Check if the float switch is plugged in correctly and if not, plug it back in.
Automate Your Submersible Pump With a Float Switch for Convenience
Connecting a float switch to a submersible pump may seem daunting, but it is a simple process that can significantly improve your day-to-day convenience. By automating the activation and deactivation of your submersible pump, you can enjoy a consistent water level without constantly monitoring it.
With the right tools and proper steps, you can safely and efficiently install a float switch and ensure your basement is safe from flooding. Remember to use the best float switch for your sump pump and keep it clean and debris-free to ensure long-term functionality.
With proper maintenance and attention, your submersible pump and float switch will work together seamlessly to provide peace of mind and a dry basement. So, don’t put it off any longer and take the necessary steps to connect a float switch to your submersible pump today.
