just in case anyone was wonderin'...this S*%t is Illegal!1

[big crush]

Got a call back in march, complaint was a loud "whoof" when the furnace lit under the floor. Check supply vent with CO monitor, but reads ok.
Under the floor find that there is about 4-5 ft of return, metal duct, so hence the loud "whoof".

Talk the prop owner into changin' the unit out for a package...THANK GOD !
Here is what we found when dismantleing the furnace.
http://www.imagewiz.net/usr/hvac1/bi...cture_0487.JPG

Every seam has been mig welded, and not that long ago.
http://www.imagewiz.net/usr/hvac1/bi...cture_0488.JPG

Showed the owner, but he "don't know nothin 'bout that ."

http://www.imagewiz.net/usr/hvac1/bi...cture_0489.JPG

[mark beiser]

It is probably the origonal welds. I have seen a lot of them that were nice and shiney, even though the rest of the HX was rotting away around them.

[dorrmann]

I agree with Mark. I think those are the factory welds.

[Senior Tech]

Factory welds...and a nice big crack in the one pic.

[ct2]

we have a guy in our shop who does stuff like that to . His name is also "I DONT KNOW" and you would be amazed at some of the $hit he pulls

The welds look new on that because the material they used to weld with is a better grade of stainless than they used to make the heat ex with. keepin mind that some types of stainless will rust

[service guy]

Thats not factory weld that looks like that sh!! they sell on T.V I think it's call alumaloy or something like that!