Kitchen sink: drain and overflow

When the kitchen sink, the process is a little more complicated than the sink. Where are the differences, and what you always have to pay attention to when assembling or removing a drain, read this post.

Parts of the sink drain

Rinse have, unlike washbasin, usually a stopper drain. Thus, the drain valve looks a little different. In addition, a sink almost always has a separately connected overflow.

The basic parts of the sink drain are so:

  • Drain valve set
  • Drainpipes and siphon
  • overflow

Discharge set

The drain set is in two parts in the kitchen sink. The strainer of the plug drain is located above (ie inside the kitchen sink). Underneath is a kit ring for sealing.

Below the sink is the second part of the drain valve. Again, this part of the process is sealed separately. The seal is located above. Upper part and lower part are firmly connected with each other by a screw. It is important here that, above all, the lower seal is intact, since the sink otherwise drips.

Drainpipes and siphon

  • dip tube
  • Siphon designed as a tube or bottle siphon
  • Sewer pipe for wall connection

The siphon goes first to the dip tube. It is connected to the siphon via an ordinary union nut connection, as usual there is a wedge seal. The dip tube may also have one or two additional ports through which devices can direct their effluent directly into the drain (such as a dishwasher or washing machine). These connections are closed only with simple rubber plates. If they are removed, you can use the connection.

Below the siphon, the sewer pipe leads to the wall connection. It can also be designed as a flexible tube.


Each sink has a separate overflow. The overflow valve is connected with a screw fixed to the overflow opening of the sink. In between there is a seal.

The overflow pipe then makes a bow and leads to the lower part of the drain valve, where it is inserted into the drain valve and secured with a union nut. Again, there is clearly a seal inside the union nut.

Clean the drain

Of the sink can often get rests and fat in the drain when flushing. To prevent this from happening, you should use a drain strainer that you place on the plug valve when water runs out. If the drain has clogged up because of the greasy rinse water and because of leftovers, you can simply open it again with a suction cup ("Pömpel") or a pipe spiral.

On the other hand, drain cleaners are dangerous chemicals that can not only be harmful to your health, but also cause great harm to the environment and water. Do not use these agents, especially the granules, as much as possible. There are also gentler remedies for cleaning drains.

Tips & Tricks

The mounting of the drain is done in the following sequence: First, assemble the drain valve, then install the siphon, then install the overflow first. Make sure that all parts are correctly aligned and do not tilt the seals. Always tighten hand-tight.

Video Board: How to Fix a Kitchen Sink Drain | Basic Plumbing