Testing a heater matrix ?

Hi all, I've symptoms of a leaky heater matrix, water in foot wells, filling the water tank up a couple times a week during winter and not at all in the summer. Most of the dash is out but before I whip out my heater matrix (2002 TD5 ES) and replace it I wonder if it's possible to have it checked out for leaks. If so how would I do it or where should I take it any tips guys?

Cheers
Al

P.S. it's been standing on the driveway since November apart from charging the battery anything I should think of before I start using it (engine wise)?

Plug one connection and put a mains pressure hose on the other connection. Turn the tap on.
You'll soon find if it leaks.