We have been in our house for 5 - 6months now and never had a problem with the water draining out of the kitchen sink...until now!
Under the sink we have the usual connections where the washing machine outlet joins the sink catchment pipe (U-bend) where it connects to another connection, connecting to the pipe running through the wall into the outside drain.
Recently the water in the sink takes longer to drain, or if we run the water from the tap into the sink it will drain up to a certain point, whereby it will backflow into the sink again.
We have also found that when the waching machine reaches certain cycles and discards some of it's water, that it will backflow into the kitchen sink, which leaves a nasty PONG in the air. It does eventually flow away.
We have also disconnected the catchment pipe (if this is the correct term) and poured a cleansing chemical (acid) down the shute which dissolves any muck in the pipes. This still does not solve the problem.
At times, there is also a waft that comes from the outside drain into the house, but we can't check it out, as the conservatory is built onto the dining room and kitchen, thus the outside drain is under the conservatory floor with the pipes boxed off.
Any ideas on a solution or what the problem might be? Could it be a gravity problem, connection pipe set-up or muck in the pipes?
Please help!
