"Tony Bryer" wrote in message
...
In article om, Dave
Liquorice wrote:
Right that confirms it. The Atlantic Conveyour will switch off in the
next 20 years, meaning that the UK will get the winters it should for
it's latitude...

But that's still unlikely to cause to a problem with a uPVC stack IMO.
Imagine a 6m CI stack sealed at the bottom, temp -5C and tip in a basin
full of warm water. Effect of temperature within stack, almost nothing
(I would guess). Do the same on a PVC stack and the inner face of the
walls probably gets to above freezing so there never will be an ice
build up.

If it is -5C outside and the stack is laying here unused for 10 hours, all
the plastic walls will be around -5C