How To Adjust The Float Switch On A Submersible Sump Pump
A float switch is an essential component of any submersible sump pump system. It automatically activates the pump when water reaches a certain level and shuts it off when the water level drops. This automation prevents flooding and protects the pump from damage caused by dry-running. Adjusting the float switch correctly ensures your sump pumps operate efficiently and avoid potential failures.
Types of Float Switch
There are several types of float switches, each designed to detect water levels differently. Selecting the right type of float switch depends on your sump pump’s setup and the environment in which it operates:
- Pump-up float switch - Activates the pump to add water, commonly used in applications like filling a tank
- Pump-down float switch - Activates the pump to remove water, suitable for draining purposes
- Tethered float switch - Uses a cable attached to the pump, allowing the float to move freely with the water level. Ideal for larger sumps with more space
- Vertical float switch - Moves up and down along a rod, making it compact and suitable for small spaces
- Diaphragm float switch - Uses pressure changes to detect water levels, ideal for murky or debris-filled environments
- Electronic float switch - Utilises sensors for precise water level measurement, requiring no moving parts
The Importance of Counterweights
Float switches will often require a counterweight for accurate water level control. The counterweight ensures the switch remains stable and triggers the pump at the right point. Different types of counterweights exist depending on the type of job and environment they’re operating in such as freshwater or chemically aggressive conditions.
Adjusting Your Float Switch
The manufacturer will usually pre-adjust the float switch so it’s the right length, but if you need to alter it manually to suit specific water or operational requirements, you can do so by changing the length of the cable.
Shortening the cable means a submersible sump pump will turn on and off at lower water levels. Lengthening it will ensure it activates at higher levels and runs for longer. Don’t forget to make sure your counterweight is securely attached, as this is essential for maintaining consistent performance.
Common Float Switch Issues and How to Prevent Them
Regular maintenance of your float switch can prevent unexpected problems, but there are issues you commonly find with them, such as debris snagging in external switches, which can prevent them from working. You can guard against this by protecting it with a filter cage or within the pump casing. Alternatively, use another level sensor, such as an ultrasonic measurement version.
Rapidly fluctuating water levels may also cause pumps to turn on and off too frequently, putting increased strain on them and requiring extra power. You can mitigate this by installing a time delay on start-up or using a high-level and a low-level switch with a PCL in a relay (high-level turns it on, low-level float turns it off).
Another Option: Non-Floating Level Sensor
These devices tend to be more expensive than float switches, but could be considered a great option should your float switch ever malfunction or fail at times when it is essential for your system to be working on a continuous basis and efficiently. For example, in wastewater treatment plants, any issues could lead to improper treatment. Non-floating level sensors tend to be an upgraded option when compared to float switches, as they usually measure water levels using ultrasonic readings or hydrostatic pressure.
Why It’s Important to Test Your Pump
Regular testing can pick up issues early on and prevent your pump from clogging or failing entirely. This is important to avoid unplanned shutdowns, potential flooding and costly, unexpected repairs. Always follow the manufacturer's instructions for correct setup and operation, and regularly test the float to make sure it’s operating smoothly. Replace it if it’s worn or damaged. At Atlantic Pumps, we offer a range of maintenance services to keep your pumps and floats running in optimum condition.
Want to know more about making the most of your submersible pump and float operations? Download our whitepaper to reduce submersible pump downtime
https://atlanticpumps.co.uk/pages/reducing-submersible-pump-downtime
