Question:
My kitchen and bathroom sink back up to each other. When I turn on cold water in the kitchen sink, it drips from under the bathroom sink. Pipes are not frozen, water runs freely on all faucets, even outside. I have water to kitchen sink and bathroom sinks off – bathtub and toilet work fine. Please help.
Answer:
Back to back drains use a double wye fitting, (figure 5 fitting) or a double san tee. If it is leaking only under the bathroom sink and not the kitchen sink, try removing the slipnuts on the p-trap and waste arm to see if the washers are in good shape and/or installed correctly with the flat part against the nut and the beveled side in the pipe. You could also use some plumbers putty around the washer to help make a good seal.