Near the end of it, the guy checked the heat exchanger and had me convinced I should get a new furnace due to some burn marks, corrosion and especially a cracked heat exchanger. He had this camera at the end of a flexible rod connected to a b&w monitor that he used to look around inside the heater.
He also took some polaroids.
I put the heat exchanger polaroid at this URL...
It is blurry, but just the place where he says the crack is has me suspicious. I could be wrong, but I now think that what he says is a crack isn't really a crack, at least not one to be worried about, just the corner seam where 2 halfs are welded together (I'm guessing) is parting some.
He did test for CO, and said he found none. No gas leak.
His recommendation is to upgrade & replace furnace & air ducts.
I'm definitely leaning toward getting a second opinion, but I thought I'd see what people in this home repair newsgroup thought as well. Was also going to try alt.hvac, but read enough posts there to know to stay away :)
Again, I admit to knowing very little about this furnace stuff, but it appears to me it's more likely he just wanted to sell me a new furnace (and ducting) than it actually being a necessity at this time.
PS: this is what he wrote on the receipt paperwork...
fall 1991: performed precision tune-up & cleaning on furnace unit. checked all safeties - OK, pulled & cleaned blower motor - OK, hydro-scanned heat exchanger & found cracks on heat exchanger on the rear bottom - informed customer, transformer @ 25.16volts, run cap @ .4 amps - OK, replaced air filter, also corrosion build-up & burn marks on heat exchanger
* checked for (co) carbon monoxide - no gas leak @ this (not readable)
* found air ducts damaged & cracked - need to replace
recommendation: upgrade & replace furnace & air ducts