Instruction: Evaluate the answerability of a question by analyzing the related document, outputting yes if the document contains information addressing the question, and no otherwise.

Input:
Question: Does the pump have a check valve to prevent backflow when it turns off?
Document: My sump pump failed and got basement flooded. Went to Sears and bought a Simer 2330 Geyser. There was about 2 inches waters on the floor. But somehow the Simer 2330 only worked a few seconds and then stopped. Read the owner's manual and did trouble shooting. Cheched airlock issue and shorted the discharge hose. The Simer still couldn't work. Got very frustrated and returned the Simer Geyser. Order this unit on Amazon. The installation was very easy. Just connect the garden hose and plug in the power cord.
I pushed the pump to a lower area in the floor. It almost sucked out all the water and stopped when I was watching TV.This unit doesn't like regular automatic utility pump which checks water present every 2 and half minute. It has a water sensor. When the water touches (about 1.3inches water level) the water sensors, the pump starts right away. After the pump pumps water down to 1/4 inch or lower the pump stops automatically. Now I put it in my window well.
Plug it in and forget it. This is great for those area's that you just never know  will get water.
I used to have water in window well after storm. We had a heavy rain last night. I checked in the morning. I didn't see water in the well. I am very happy I had this one.
Didn't last that long, maybe 4 months of outdoor use. I was using to keep water out of a cellar entrance that wasn't build with a drain.
Answer: no