DaveReading
Don't suffer fools gladly (must try harder!)
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Hopefully a question about stupid plumbing, rather than a stupid question about plumbing ...
The loo downstairs (35+ years old) had become almost impossible to flush, so I decided to replace the syphon with a more up-to-date one.
That involved removing the cistern, which was straightforward enough, but on refitting it and replacing the ancient, squashed flat doughnut with a new one I found that cistern was riding a cm or two higher than before. There was enough wiggle room in the fill pipe to reconnect it, but the overflow pipe would no longer reach the union on the bottom of the stack pipe, and I managed to break the drain pipe in trying to bring them together (I know, I know ...).
No problem, or so I thought - the necessary replacement pipe and a 90 degree elbow were only a couple of quid, and I got the hang of using solvent weld. I decided I might as well replace the overflow stack while I was at it.
That's where things started to go wrong. The original drain pipe was grey plastic, relatively thick-walled and 22 mm O/D. It was a snug fit inside the bottom of the stack pipe, which was made of a fairly flexible plastic such that a compression nut would produce a nice watertight union when nipped up (bearing in mind that it was only the overflow, so no real pressure).
The new stack pipe, although made of a less flexible plastic, has the same internal diameter, so the original 22 mm pipe would have been a snug fit and probably watertight, even allowing for the fact that the compression nut wouldn't really be compressing anything. Unfortunately, the standard nowadays for overflows is 21.5 mm O/D, which rattles around inside the stack pipe, and doing up the compression nut does nothing to make it watertight.
Leaving aside the fact that the plumbing industry seems to have standardised on two parts of an overflow system that don't fit together, can I ask if anyone else has encountered this problem and, if so, how did you resolve it ?
The loo downstairs (35+ years old) had become almost impossible to flush, so I decided to replace the syphon with a more up-to-date one.
That involved removing the cistern, which was straightforward enough, but on refitting it and replacing the ancient, squashed flat doughnut with a new one I found that cistern was riding a cm or two higher than before. There was enough wiggle room in the fill pipe to reconnect it, but the overflow pipe would no longer reach the union on the bottom of the stack pipe, and I managed to break the drain pipe in trying to bring them together (I know, I know ...).
No problem, or so I thought - the necessary replacement pipe and a 90 degree elbow were only a couple of quid, and I got the hang of using solvent weld. I decided I might as well replace the overflow stack while I was at it.
That's where things started to go wrong. The original drain pipe was grey plastic, relatively thick-walled and 22 mm O/D. It was a snug fit inside the bottom of the stack pipe, which was made of a fairly flexible plastic such that a compression nut would produce a nice watertight union when nipped up (bearing in mind that it was only the overflow, so no real pressure).
The new stack pipe, although made of a less flexible plastic, has the same internal diameter, so the original 22 mm pipe would have been a snug fit and probably watertight, even allowing for the fact that the compression nut wouldn't really be compressing anything. Unfortunately, the standard nowadays for overflows is 21.5 mm O/D, which rattles around inside the stack pipe, and doing up the compression nut does nothing to make it watertight.
Leaving aside the fact that the plumbing industry seems to have standardised on two parts of an overflow system that don't fit together, can I ask if anyone else has encountered this problem and, if so, how did you resolve it ?
