We had to replace our furnace and hot water tank today. You'd think that with modern technology it'd be a fairly simple thing:
1) Unplug old furnace, tank. (Note: Turn off gas and water before you do this.)
2) Plug in new furnace, tank. (Note: Turn on gas and water after you do this.)
But no, it's never that easy. This is what the process sounds like: BANG BANG BANG BANG. BANG BANG BANG BANGBANGBANG. WHIRR WHIRR BANG BANG. All day long. BANG WHIRR BANG.
I don't know if the installers actually built them from scratch with pieces of scrap metal, but things seem to be humming along nicely now.