Solvent weld PVC reduce 100mm to 21.5mm

[Donkmeister]

I need to reduce a 100mm pipe to a 21.5mm pipe (i.e. 100mm PVC duct down to PVC overflow pipe).

I have found a 40mm to 21.5mm reducer, but am drawing a blank over a 100mm to 21.5 (or 100 to 40mm) reducer. I had wondered about using rubber soil stack components but these are 4"/110mm rather than 100mm.

Any thoughts?

(You may have guessed this is in order to build a condensate drain-off for a bathroom extractor fan duct... there is no room for a standard concentric condensate drain hence I intend to use a 3-point Y-piece with the lowermost connection reduced to 21.5mm pipe to drain off condensation.)

 

[Donkmeister]

Is there such a thing as a 100mm weldable PVC blanking plug? If I can get one I can fit a 21.5mm bulkhead connector to it. Not ideal as I would have a certain amount of water pooling before it drains off but one possibility.

 

[Newboy]

Try a McAlpine DC2-BL to get 1½" down to 100mm

or a DC4-BL & ZT31M with a suitable holesaw