Whenever I run the laundry washer, which is downstairs, the upstairs bathroom's toilet and tub begin to overflow and back up with dirty water. I have checked to see where the washer drains to and it goes directly into the sump pump. I do have city lines as well. The main line has been snaked multiple times and seems to be clear since when we use any other appliance and toilet or tub there is no problems. But when I use the washer, it drains into the sump pump and somehow comes up to the upstairs bathroom and starts to fill the tub and toilet. Is there a clog in my lines somewhere or is my sump pump bad? I am stumped by this and need some advice.
Thanks
Mike Wendth