Do be aware if you phone the insurers it could be difficult to back out of a claim if you think its not worth it I would ask am I covered if I had a leak from a burst pipe and whats the excess rather than say youv'e had one!!!!!!!
I should imagine the first question will be why did the pipe split? Was it due to you leaving water in which then froze? If yes then it should be an insurance claim, if not and it is a manufacturing fault then it should be a warranty claim (assuming it's under warranty still).
However, as has been mentioned above, check on the damage caused and the cost to repair as it might not be worth claiming on insurance if it's the former.