Material

This was found on a 10 year old furnace. The material looks to be abestos but on this new of a furnace?

The furnace may be 10 but the duct work looks older.

Appears to be ACM like substance and it looks friable.

It sure looks like it, I would write it a suspected asbestos, Recommend a qualified contractor to review and estimate repairs.

The house older than that? May be replacement furnace with old duct work intact.

Gary,

That is an asbestos tape that was used on all duct seams, back then.

Recommend encapsulation of “exposed asbestos looking material” due to it being friable.