Ray,
Thanks for the reply, with this explanation this is now clear for me. I think I will go for the option of replacing the triacs as this seems to be the simplest option. I have found a supplier where I can buy the MPSA13, as the 14 does not seem to be stocked so much here in the Netherlands. I did find one supplier but he only supplies to registered company’s or professionals as with a lot of the electronic suppliers in the Netherlands these days.
Bren