I recently bought an older house with a septic system. At some point the previous owners installed a laundry setup in the basement, with the washer draining into a laundry tub attached to a sump pump. The pump pushes up about 6ft to a pipe out to the septic.
This pipe is shared with the kitchen sink and dishwasher, immediately above. Nothing else is connected. The kitchen sink has an AAV under it, but there is no connection to a vent up to the roof.
The pump box also has a vent, but it's behind the pump (I think). Every time the laundry pump runs, the water in the kitchen sink trap blows out. As the AAV only lets air in, not out, there's nowhere for the air to escape, so it comes up the sink. So, I need to connect it to a vent, but I can't find any dedicated vent pipes in the basement, only waste/soil pipes. The nearest is only a few feet away.
My question is, can I just connect a vent from somewhere in the laundry/kitchen piping to the nearby waste pipe, and use its stack as the vent, or do I have to somehow run a stink pipe up three floors of wall? Do I have any other options?
Additionally, there's a random capped pipe leading up into the wall immediately behind the basement pipes. I suspect this is actually a drain from before they remodelled the kitchen and moved the sink. Would explain why the septic connection is there. Is there a way I can determine if this is connected to a vent, and if it's still intact?
This pipe is shared with the kitchen sink and dishwasher, immediately above. Nothing else is connected. The kitchen sink has an AAV under it, but there is no connection to a vent up to the roof.
The pump box also has a vent, but it's behind the pump (I think). Every time the laundry pump runs, the water in the kitchen sink trap blows out. As the AAV only lets air in, not out, there's nowhere for the air to escape, so it comes up the sink. So, I need to connect it to a vent, but I can't find any dedicated vent pipes in the basement, only waste/soil pipes. The nearest is only a few feet away.
My question is, can I just connect a vent from somewhere in the laundry/kitchen piping to the nearby waste pipe, and use its stack as the vent, or do I have to somehow run a stink pipe up three floors of wall? Do I have any other options?
Additionally, there's a random capped pipe leading up into the wall immediately behind the basement pipes. I suspect this is actually a drain from before they remodelled the kitchen and moved the sink. Would explain why the septic connection is there. Is there a way I can determine if this is connected to a vent, and if it's still intact?
