Agh the old copper heat exchanger - prochems favourite part! Don't tell me it froze right? Best thing to do is either haggle with prochem (my father in law always gets a better price than I do
) or if money is a bit tight, blank it off until you get some cash in. It will take a bit longer to warm up as that is why the first exchanger is copper and not stainless like the other 2.