Burnt Out Contacts on CC relay

I have recently had problems with the Pulsacoil 2000 installed in a flat. The off-peak was failing to heat the water, however the on-peak boost worked OK.
I have had an electrician visit over the weekend and he has told me that the Off-Peak contacts in the CC relay are burnt out.
Having read some articles on this site I assume that the problem has been caused by the lack of water in the header tank requiring this relay (also known as a Dry Fire Protection relay) to continually operate until it has burnt out.
I have been told that this relay appears to be rivetted to the board - is it possible to replace just this item or wire in a replacement?
If not does the circuit board need to be replaced?
I have been told that there is a moulded type plug connector which appears to make replacing the board impossible without re-making this plug - is this a problem?

What has burnt out
THe PCB at the top right hand corner of the unit?

Hello,
I was just wondering how you solved the issue, I think I've got the same problem with a burnt out relay.
Did you just buy a new one? If so, where from?

Cheers
Simon