BrianWithAnI
New Member
I replaced my washing machine and to make more space in the small laundry room did not replace the laundry tub. The original drain configuration had the laundry tub drain straight into the p-trap with a T off the line to a standpipe for the washing machine. The drain runs into the wall behind the laundry room, makes a left turn to the exterior wall, then down to the sewer in the basement floor. This is not the main stack. Where it enters the sewer it connects to a 3" line with a cleanout on top. I discovered today there is no vent on that drain. The house was built in 1994 so I have no idea what the code in Ontario specified for the time, but I'm guessing the plumber used the laundry tub drain as the vent for the washer and the standpipe as the vent for the laundry tub.
I now have just the standpipe going straight into the trap. There is not much horizontal space between the standpipe and the washer but there is room on the opposite side. Do I need to install a T on the standpipe and put in an air admittance valve? Is this acceptable?
I now have just the standpipe going straight into the trap. There is not much horizontal space between the standpipe and the washer but there is room on the opposite side. Do I need to install a T on the standpipe and put in an air admittance valve? Is this acceptable?
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