My clothes washer drain backs up after about 10 seconds. If I wait for 15 seconds it will accept another 10 seconds of pumped water--but, it backs up again.
My kitchen & clothes washer are both connect to the same main drain line (~20 ft apart). I used an electric powered 3/8" drain snake to clean out that main line up to 75 ft. The kitchen drain drains perfectly, however, the clothes washer drain still hasn't improved.
I used a 5/16" drain snake on the clothes washer drain, however it would not go very far into the piping. I imagine it gets caught at the p-trap (which is inside the wall) and that is probably where the clog is.
I live in an older house & I don't want to use caustic drain cleaner chemicals in my old drain pipes to clear the clog. What is the next best DIY alternative for clearing out a drain pipe that has a p-trap in the wall or in the concrete floor (my 1st floor shower drain may soon need cleaning too)?
p.s.: There is NO clean-out access port in the plumbing for this drain.