Toilet overflow connector question

[mattdiy]

Hi all, I am a DIYer hoping for some help! I am wanting to connect a toilet overflow to a copper 22mm pipe instead of plastic pipe - question is, what connection do I use to connect the 22mm copper pipe to the toilet? I looked at a brass tank connector but the overall thread diameter is approx 30mm and the hole in the top of the toilet cistern is closer to 25mm. Can anyone suggest a suitable fitting? Or if using a standard plastic toilet overflow connector, how would I connect this to a copper 22mm pipe? Thanks in advance!

 

[JCplumb]

You very rarely need an external overflow, most flush valves have their own overflows where it goes into the pan if the water level gets too high.
I honestly wouldn't bother with an external overflow unless there's no other option.

 

[mattdiy]

Thanks for your helpful reply - I suspect that will cover my one toilet (approx 6-8 years old that doesn't appear to have had an overflow connected to it in the past - any clues as to how I check if it has an integral overflow that goes back into the pan?). The other toilet I am installing is a vintage model (1940s!) and I thought a copper pipe would look the part - any ideas on how to connect a copper overflow pipe to this would be appreciated.

 

[townfanjon]

I have never done it but a 22 mm compression should do .

Edit.. 22 comp coupler

 

[mattdiy]

I have never done it but a 22 mm compression should do .

Edit.. 22 comp coupler

 

[ShaunCorbs]

Hold the ball valve down does the water flow into the pan when it's about level with the top of the flush valve

 

[mattdiy]

I have never done it but a 22 mm compression should do .

Edit.. 22 comp coupler

Thanks for your reply, much appreciated - would that be a plastic or brass compression fitting?

 

[mattdiy]

Hold the ball valve down does the water flow into the pan when it's about level with the top of the flush valve

Will give it a go, thanks!

 

[townfanjon]

Will give it a go, thanks!

Brass pal , I cant see why it wont work , overflow pipe is 21.5 , use a copper olive , not brass.
An overflow pipe is not under any pressure so should do .

 

[Ric2013]

any clues as to how I check if it has an integral overflow that goes back into the pan?).

Also worth checking if you're doing this that there is a reasonable air gap between the fill valve and the water level when overflowing so as to protect the mains against the risk of back contamination under conditions of multiple faults (i.e. water level creeps up for whatever reason and then mains pressure falls).

If you are using an old-fashioned BS1212 part 1,2, or 3 valve, or a Torbeck (look them up), you can check there is an air gap between the valve 'spout' and the water. With some of the the weirder modern valves it's a bit less obvious, but so long as they are installed as per manufacturer's instructions, then they should be fine.