Install a cistern


Most of the toilets that can be found in households in Germany require a toilet cistern to flush the water. Especially in times when water and electricity have become very expensive, the absence of a water-saving key quickly turns up. Likewise, if a cistern permanently loses water. So many reasons why currently more toilet cisterns are exchanged than usual. Below you will find a detailed installation guide to assemble your cistern yourself.

Designs of WCs with cistern

Apart from the flush valve, which can hardly be found in Germany, all other toilet flush systems require a flushing cistern in which the water for flushing is stored. Otherwise, there are differences only in terms of types:

  • Pre-wall installation with integrated cistern (flush-mounted mostly)
  • Toilets with cistern attached
  • Cisterns for wall mounting, conventional
  • Cisterns for wall mounting, high hanging (mainly in old buildings)

Special features of the wall installation

When cistern integrated in the prewall component renewal is not readily possible. Either it is a drywall or wetwall pre-wall element. Then either the drywall components (plates, stands) or building blocks and plaster (aerated concrete block, brick, etc.) must be removed. Therefore, we describe below the installation of a cistern as a toilet attachment - in addition to the pre-wall installation one of the most common toilet systems. How to make the toilet pre-wall installation, you can find out here.

Step-by-step instructions for mounting the cistern (WC)

  • cistern
  • Accessories such as HT pipes, bends, screws, etc. (mostly in the cistern)
  • possibly angle valve
  • possibly flexible hose (stainless steel sheathed)
  • Lubricant for rubber sealing lips (HT pipes)
  • Hemp for sealing on external threads
  • Wasserpumpenzange
  • Fork / ring spanner set
  • Ratchet or ratchet box
  • Screwdriver (flat, crossed)
  • Drilling machine with appropriate drills (wall mounting)
  • spirit level
  • Meterstab
  • Pen for marking
  • Saw, fine-toothed
  • alternatively jigsaw
  • Stanley knife

1. Install a cistern

If the old cistern is still installed, it must first be removed. To do this you first have to turn off the water - either at the main tap or at the angle valve (if already available). Then the toilet ceramic is cleaned of deposits such as lime, urine stone and other dirt.

2. Interior of the cistern

Depending on the design, it may be necessary to install the mechanics inside the cistern already. It is a drain valve with overflow, operating mechanism and the inlet valve with float. Each cistern manufacturer attaches a corresponding installation manual. It also provides information on whether the components of the cistern should be installed before or after the installation of the box on the toilet.

3. Prepare water connection and WC inlet

If there is no corner valve, you can install it now. The flex hose is then connected to it. For external threads, wrap this with hemp. Then check the pipe lengths and dimensions for the toilet inlet. Usually there is a screw-on socket on the toilet ceramic side. Rubber seals must be rubbed with lubricant.

4. Prepare and install cistern assembly

Now organize the screws and washers according to the manufacturer's instructions. The elastic rubber disc must be inserted between the cistern and the toilet ceramics. Carefully lift the cistern onto the WC ceramic so that the inlet pipes fit together without jamming. Then insert the screws through the cistern into the ceramic and unscrew the nuts from below. But do not finally tighten them so that you can still move and fix the cistern (depth and side).

5. Install water connection and toilet inlet

The prepared pipes and water connections can now be mounted.

6. Align cistern and tighten, further final work

Now align the cistern centrally (sideways and in depth) on the WC ceramic. Then tighten the fixing screws.

If the components of the cistern are finally installed, the time has come. Proceed exactly according to the installation instructions of the manufacturer.

Turn on the water and check the entire assembly for any leaks. Finally, the lid is placed on the cistern. For plastic lids this is attached with clips. Heavy ceramic or sanitary porcelain lid, however, are usually only applied.

Tips & Tricks

If you want to renew the cistern, because the water in the cistern constantly runs after, you should first try to descale the toilet cistern. It is quite possible that you must also adjust the float and thus the inlet valve of your new toilet cistern. Here you will find a corresponding adjustment instructions: Set toilet flushing.


Video Board: How to install toilet cistern (part -1)