Why is my Bitmap returning null?

The dirty water from the washing maching is returning from the drain pipe why?

• dirty water is not going thru the drain pipe its returning back and spilling on the floor of the laundry room why?

• Answer:

  You have an obstruction in the pipe somewhere. If the problem is only with the washer, and water is not backing up in the toilet or tub, then the clog should be localized near the washer. Rent or buy a snake from your local hardware store. There should be clean-out plug at or near where the drain hose enters the pipe. If it's on an exterior wall, check the outside. Remove the cap and run the snake through. When you hit the clog, you'll feel resistance. Pull the snake out and clean it of lint and such and run it through again. You should feel no resistance now. Pull the snake out, replace the cap, and run some water through. It should run clear now.