Thanks for the replies guys, especially to RayT, I think I might have a go at repairing it myself and give myself a well deserved pat on the back after i fix it (fingers crossed!)
James80 also thank you for the website to purchase a new diesel heating system, if i was going to puchase one i would consider going there as the prices were to my liking. So i will keep that in mind for the future (even though it has generated some quiestioning)
Again, thank you guys for all the help, all the best guys and happy sailing,
Adam