Split in Hepworth in line plastic connector

[baz wheater]

I noticed a split had occurred in the centre of a in line connector, (orientated towards the top to bottom of ends) one end was connected to 15mm plastic pipe and 15mm copper at the other. The pipe work was connected to the water feed pipe into a water tank in the loft.
I traced the other end of the pipe and it connected to copper pipe which appeared to connect to a expansion vessel downstairs.
Has anyone any idea why it split where it did as the weather was good with no below zero temperatures.
Caused loads of water damage.
Cheers

 

[ShaunCorbs]

Any pics?

 

[baz wheater]

Any pics?

 

[baz wheater]

There you go mate

 

[king of pipes]

Looks like it has frozen to me when we had the bad weather. Kop

 

[baz wheater]

That's what I thought but the temperature was about 11 degrees so I don't think that this was the case, but just can't think of any other reason for it.

 

[townfanjon]

Longshot , was the fitting under any stress from the copper pipe ?

 

[Best]

Mains pipe will be the first to freeze due to lower water temperature in winter.
Maybe it got partly damaged when frozen and only split now.
But those plastic fittings are well known to snap if under stress. The plastic in the fittings is just thin and brittle