Hot spots on welds-Heat Exchangers

These are two pictures inside a Ruud furnace built in 1998. 90,000 BTU/HR input. Both hot spots have direct flame impingement. Not sure how to write this up. My gut tells me it’s a failure point but there was no CO detected in the plenum. Looking for some suggestions. Thanks!

Example:

The visible area of the 16 year old furnace heat exchanger showed two hot spots. Although no carbon monoxide was detected in the plenum at the time of the general home inspection, I recommend a qualified HVAC technician more fully examine the furnace and complete the annual checkup now to maintain a safe and efficient operation of the furnace.

You do not get a level of CO detection from this condition. You can however call in a Indoor Air Quality Investigator and they will pin point it in about a 1/2 hr.
I also on many occasions warned those who feel that IAC2 gives you the right to advertise that you do Indoor Air Quality Investigation is wrong also.

Nothing to write up…

I like this, Thanks