What's the difference between a sump pump and an ejector pump?
A sump pump is placed in basement floors, below ground level, and in a small pit of 20 or 30 gallons size.
Around the house, under the house, and perhaps a stairwell, tubes will be placed to direct water from those places into the sump pump pit. As the water level increases the pump is turned on by a float device, and the water is ejected away from the house. It is important that the sump pump collects and ejects that water away from the house. Houses don't make very effective boats.
I wrote a blog earlier this year on how to choose a sump pump. You can read it here.
An ejector pump is very similar, but has a different role. The pump is intended to eject water from a basement bathroom that is below the graded drain level up and into the main plumbing for the house so it can be sent to the sanitary sewer at the street.
The pump mechanism is slightly different as it has to pump not only fluid but solids into the plumbing.
Other than that an ejector pump is a glorified sump pump.
Seeing the sump pump and ejector pump side by side, I looked to see which was an ejector pump and said and involuntary, "Uh, oh..."
My clients wondered why. Explaining what an ejector pump is and its function, we returned to the bathroom. The toilet in the bathroom was dated 11 years after the birth date of the house, along with newer light and plumbing fixtures, so I determined that the bathroom (and part of the basement) was put in post house construction.
That explained the ejector pump, as the builder would have left the empty pit, along with rough plumbing, in place for a future bathroom. The future had arrived.
My uh oh was because there was a sizable gap all around the discharge tubing where it passed through the lid. An ejector pump is pumping unsanitary and smelly water, and the lid must necessarily be hermetically sealed. And for obvious reasons! You can see where it appeared to have leaked, um, sewage from around that opening!
To demonstrate I turned on the bathroom water and flushed the toilet a few times to demonstrate that the pump worked. And I warned that the room would soon smell like sewer gas. My statement soon proved to be very true!
My recommendation: sometimes it's the little things that make for proper installations! It could be that these sellers just thought that installing the basement bathroom would result in a sewer smell for a while, but saw that eventually it would go away! Nobody wants sewer gas to leak into the house and the ejector pump pit in this house was a source for that. While the fix is simple, it is important! Remember the old saying - sewage be any other name smells just as, well, smells the same.