WC Cistern standard outlet thread size.

[MungoDundas]

Hi there,

Sorry to bother you, but I was wondering about some guidance.

Our low level surface mounted ceramic Armitage Shanks cistern has developed a crack, fair enough as it must be 30 years old plus.

The central threaded outlet for the pipe to the WC pan appears to be about 45mm dia.. I’d reckon the plastic pipe from Cistern to WC Pan is about 40mm dia.

On what I took to be a modern equivalent cistern at the local wholesalers, the outlet seemed to be more like 50mm dia.

Can one get an adaptor/reducer to accommodate this difference and accept the existing plastic pipe?

Mtia.

 

[Newboy]

The central threaded section sticking out of the bottom of the cistern is the siphon - the connecting pipe between pan and cistern is the flush pipe either 1piece for low level or 2/3 piece for high level. If you need to replce the flush pipe then buy a new flush pipe - the OD is slighly smaller the 40mm waste pipe.

 

[Softus]

Many new cisterns come with a compatible flush pipe (for obvious reasons).

 

[grrinc]

The old lever and syphon style cisterns have the smaller hole you mention. The newer push button and dump valve style cisterns have the larger holes. If you are looking to put one of the newer cisterns in place of your old one ( the old style are still available by the way ) then you can get a flush pipe that has its own reduction moulded into the pipe. You dont have to buy a reducer.

 

[Softus]

Why on Earth does anything need reducing?

 

[grrinc]

When the OP mentioned a pipe from the cistern to the pan, then I am assuming he has a low level wc. If this is the case, and he is just replacing the cistern only with the new style cisterns he saw from the whole sellers, then he will need to use a flush pipe that reduces from the new larger style to the old existing style. And these type of flush pipes are available. I know this, because I fit them.

However, if I have misread the OP said, than I apologies.

 

[Softus]

No need to apologise, and no need to assume low level because it's in the first post.

What I meant was: why reduce anyway? Just buy a new cistern, with a new flush pipe, and use right cone on the pan. I hesitate to use the phrase, but "bish bash bosh" springs to mind.

 

[grrinc]

**realisation dawns**


Obviously I am just looking for problems to help with!! Of course you are quite right. I really ought to be finishing my quotes and getting an early night.

 

[Softus]

Obviously I am just looking for problems to help with!!

In which case you should stay and make a lot of punters very happy. I too am trying to finish paperwork whilst getting drawn in to topics.

 

[MungoDundas]

Thanks a lot for the help.
Is this the right forum to mention the old joke:
What's the difference between a jazz drummer and a plumber?
At least a plumber can feed a family of four!