Periodically and seemingly randomly our washing machine outlet lets out an extremely loud gurgling noise for maybe 5-8 seconds. There is no correlation with use, and no adverse effects that I have noticed (leaks etc.).
The machine is a modern stackable system, about 3 years old. The plumbing in the house was all new 3 years ago. The machine is on the second floor of the building. I had always ascribed the gurgle to some action taken by our neighbors on the first floor (two unit condo association in a 3 floor Victorian), but it just happened again when they are out of town.
The noise seems to come from the wall right near the outlet, which is a 2" black accordion plastic hose that goes from the bottom of the washer up about 3' before dropping into the wall. The hot/cold source lines come out in the same spot. Any trap or venting is behind the drywall.
Seems like a mystery to me. Any ideas? My only guess is that maybe the washer has a slow leak on the input tap, so maybe I am wasting water. I never hear any dripping or leaking sounds though.
Thanks for any thoughts that you may have!