How to find end of duct. Fog machine?

[wglover]

Hi folks,
I'm trying to locate the end of a duct that is disconnected from the unit in my attic (don't worry, there's no venting into the attic- it was previously sealed). The problem is the duct is buried under piles of blown-in cellulose insulation. Had an A/C professional crawl around for 1 hour trying to find it with no luck. I'm thinking of using a fog machine to blow in smoke through the vent and find it that way. Is that a good/bad idea? Any alternatives?

Note: Once I find the duct I'm going to hire a pro to replace it!

Thanks in advance!

[wglover]

No thoughts? Alright, I'm gonna bite the bullet and give it a try- it seems that fog machines are sometimes used for finding holes in ductwork, so I suppose this procedure might work.

[beenthere]

Fog machine should work.

[kangaroogod]

Not sure what to say......

[Joehvac25]

I would think you could start at the beginning (furnace) and follow to the end or the area the register is that's not connected?

[DeltaT]

Hire a plumber with a TV snake.

[duckman06]

Hire a plumber with a TV snake.

Agree. I do this from time to time when can't see the duct. My company also does plumbing as well so just use one of the plumbers camera and go into the duct work and look for problems.

The thing with the camera is that you have to keep track of how much cable you run in feet wise and rember it's inside the ductwork so you can't see it from outside. So you could find the end but with out a locator (plumbers have also to locate the camera and line). You simply go over area where u think it might be and locator will sound alert when you get close to the camera .