22mm overflow pipe and fittings?

[NeilPalfreyman]

I've just discovered a problem with a very old 22mm plastic overflow pipe on our central heating tank.

I need to add a short additional section using straight and elbow joins, but I can only find Flowplast 21.5mm in Screwfix.

Is it possible to get 22mm pipe and connectors as it's not really feasible for me to replace the whole lot with flowplast.

Alternatively is it possible to join 21.5 and 22mm? I was thinking plastic compression, but I don't seem to be able to find any for this diameter plastic.

 

[SandyLyon]

Firstly there is solvent weld and Pushfit overflow systems available and from memory there was an odd sized overflow on the market years ago, I think it was Osma, you had to use adaptors to convert it to standard overflow.
Cut a small piece off and take it into a plumbing merchant PTS, City Plumbing, Graham, Plumb Center etc

 

[Nige F]

Mc Alpine R1M universal overflow compression fitting

 

[dilalio]

'Gently' heat the larger diameter pipe until malleable and push the smaller diameter pipe into it whilst turning constantly. This will 'flare' the end of the larger pipe and create a female socket. Keep doing this until the plastic cools and then you can pull apart and solvent weld one into the other as normal! A hairdryer should be enough for the heat but keep rotating the pipe to evenly distribute the heat and do not burn it!

 

[Agile]

Why are you unable to replace the whole length?

The tube only costs about 40p per metre so is very cheap!

Tony

 

[NeilPalfreyman]

Thanks for the replies, guys.

I managed to get a couple of 22mm to 21.5 reducers from a local plumbing store. They fit snugly on the 22mm and reduce down to a diameter that suits a flowpast straight connector.