Washer drainage issue with washer and sink

[Ryan M Kallman]

High efficiency washers that's draining into The kitchen sink, When the house was remodeled the contractor removed the vent stack that went through the roof. Will the addition of an air admittance valve between the kitchen sink and the washing machine drain Prevent the backup from taking place. The drain line Starts at the kitchen sink, The washing machine "y"s in and the line continues on to the main drain trunk. There is no vent on the side of the drain stack. The washing machine has a p-trap and the kitchen sink is plumbed terribly as well. I have enclosed a picture of kitchen drain.

 

[Tuttles Revenge]

Your post sorta reads backwards.. Asking the question before providing the problem... But... it sounds and looks like almost everything there having anything to do with the drain is Wrong. I'm not certain if you are having a problem with Leaking or if the drain is Backing up/not Draining. The towel sorta indicates a leak.

But a properly installed sink has a P-trap to keep sewer gasses from entering your living space. The p-trap needs to have a vent to allow Air In.. An AAV would do that. A vent through the roof or an AAV function is to prevent the p-trap from siphoning out as water is exiting the drain. The trap connects to the drain by way of a trap arm, which is the first horizontal pipe after the trap weir. That trap arm connects to the drain and the vent with the vent/AAV being Vertical so that its drawing air in as the drain water continues downwards via gravity. From the above picture, the drain coming up through the cabinet needs to be a full sized drain.. either 2" or 1.5" if that was what was installed previously and 2" is not available. That vertical pipe needs to have a Tee installed on the vertical so that the horizontal branch becomes the trap arm connected to the p-trap and the vertical branch of the tee becomes the vent with an AAV installed at least 4" above the trap as per plumbing code or the manufactures instructions.