Avoid these common mistakes when installing a pump station

Pumpstations Direct provides packaged pump stations that are comprised of submersible pumps, polyethylene chamber, lifting chains, floats, a controller, and pipe kits. Once the pump stations are delivered to site and installation commences, it is not uncommon to run into issues.

To help you avoid making these common mistakes we’ve identified them as well as some tips on how you can make sure these don’t happen to you.

Vehicle loading on the poly chamber:

The polyethylene chamber is lightweight making it easy to install but is not designed to be vehicle load bearing. If a cast-iron cover sits directly above the polyethylene chamber, it will pass the weight of the load from the surface onto the chamber - weight the pump station is not designed to handle.

Solution:

Make sure you know the dimensions of your cover as well as your paving detail to allow for proper excavation depth, and if it will be subject to vehicle traffic. Set your chamber down at least that far, and ensure you tie your cast iron cover through to your paving detail, or alternatively encase your entire poly chamber in concrete.  Installation instructions for Class D applications are available with the dimensional drawing of the pump station supplied at time of quote.

Insufficient cables:

Submersible pumps and level floats use a special immersible cable designed for use in water and wastewater.  This cable is usually 10m long by default on most pumps and floats. Inaccurate measurements for the required distance of pump cables often hold up installation due to an electrician is required to extend them when 10m is not long enough.

Solution:

Make sure you measure from the chamber depth and the length the cables that it must run up the wall to connect to the controller. These are the measurements most often forgot about. 

Absent or improper concrete ballast:

If a pump station is not installed with a proper concrete ballast the bottom of the chamber might lift, or the pump station may push through the finished surface. This is often referred to as buoyancy and is caused by the upward pressure of water table on the pump chamber.

Solution

Our Installation and Operation Manuals (IOMs) include information regarding this, but in general the concrete should encase the base of the pump chamber all the way up to the first rib of the chamber.  The chambers also have tie in points for reo at the bottom that anchor the chamber to the concrete ballast and counteract the buoyancy pressures.

 

Weights not attached to float cables:

Not attaching weights to the float lines will often cause the float to not trigger, as the weight provides the pivot point in the float cable.  Without these weights the pump station will overflow.

Solution

Attach the weights to the float lines at the pivot point before you run them through the conduit. As a last resort, if you’ve already run the line, you can use utility grade zip ties to attach the weight.

Miswiring the high-level alarm and stop float switch:

After running all the cables through the conduit it can be easy to mix them up when you connect them to the controller. If your alarm is sounding when your pump first engages, this is a likely cause.

Solution

Double check the cables before connecting them, or even label the ends prior to pulling them through the conduit. Controllers include wiring diagrams to show where the correct cables should go and also contain directions in the IOM.

Uncleared hard debris impacting pumps:

Rocks and other hard debris might get caught in the pump impeller causing pump damage or jamming.  This is the most common malfunction in a stormwater pump station and can result in the station overflow if the pump station is not maintained.

Solution

Clear out the bottom of the pump chamber if debris falls in during installation and flush the pipe work to make sure it is clear as well.  Once operational, a regular checkup of the pump station to clear any debris and assess ‘wear and tear’ can help keep your pump station operational.

For more tips and tricks on preventing jams on your stormwater pump station, get in touch with a Pump Stations team member for assistance.