vent stack leaks when sink drains
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vent stack leaks when sink drains
When kitchen sink or dishwasher drains, vent stack leaks. After J-trap under sink, 2" drain from kitchen goes straight thru floor into basement; drain goes into the angled part of a y-branch. The branch top (straight part) goes up to the vent stack into wall & thru roof. The branch bottom extends straight down to basement floor drain. House is old & metal vent stack has a rusted hole just above the floor joists. The hole is located ~ 2 feet above the y-branch junction. Prior to the rusted hole, I never had a problem with sink draining properly. I can fix the vent hole, but my question... why is some drain water going up ~ 2 ft into the vent stack while the sink is draining? Until the hole, I never knew the water was going up the vent. Is this normal? I thought the vent would allow for all the drain water to flow straight down.
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No bubbles or unusual noises when sink drains; however the pvc drain line in basement does vibrate a little when large rush of water is going down. Does not affect bathrooms at all; bathrooms drain directly into main drain stack on other side of house. Only kitchen sink is connected to this drain line which travels under entire width of basement floor (~ 30 ft) before connecting to main drain stack. Are you thinking partial clog might be in vent stack? or in drain line? The odd thing is the kitchen sink drains just fine; it does not back up or drain slow. So are you saying this condition (some drain water traveling partially up vent stack) is not normal?