Major rust at furnace supply. Please help Newb

Hey guys. This is a condo with the furnace and water heater in a closet outside of the home on the front patio. It was a super tight fit in this closet with the furnace and water heater. The rust above the furnace was pretty significant and I also noticed small amounts on the water heaters flu joints. What is this likely from ? I also see this electrical junction box right under the rust area which seems super hazardous. Thanks guys!!!

It is very simple…
Call out what you see and move on…OK?

Sooo don’t learn? Don’t try to find out what causes problems in homes to Help benefit my future clients ? Just point out a problem and say “there’s a problem!” Then when anyone ever asks for some possible insight say “don’t know just a problem”

Roy is from Fla you should just forgive him. He knows not!!! his brain is sun cooked

I saw the corner of a humidifier in your pic I suspect that is why you have rust

That looks like a venting issue. Water is condensing in flue. Numerous causes possible. Regardless, someone is going to have to figure out why exactly.

Like Roy said … ID the concerns, recommend a specialist R/R, then move.

Can be more than one reason AND out here we’re all just guessing. IF you really wanta learn be there when the Tech is there

Due to the system design, there was limited visibility and restricted access to the heat chamber. We were unable to fully view or examine the entire heat exchanger and burn chamber. Verifying the integrity of these components would require intrusive testing by a heating specialist.

There was excessive rust, corrosion and scale at several areas inside the unit and at the flue. This type of deterioration can be caused by varied reasons, BUT can often be the results of leakage from more than one source, or an improper venting issue [Clean and servicing of the unit recommended]. Check it for proper operation and verify the full integrity of the heat exchanger. Cleaning and servicing sometimes reveals hidden defects if present.

Have a competent and licensed heating specialist read the report; evaluate and review the system conditions; then service, modify or repair any deficiencies OR unreliable conditions as needed to safely and properly correct them.

I noticed that and 5 other things that could be an issue.
OP did not collect and provide sufficient information to make a wild assed guess.

Lol y
Good eye sir thank you very much

thank you everyone I learned a ton in this thread… and Roy… I’ll continue to pray for you. Someday you’ll find happiness lol

Condo unit? Is there a unit above as well?

How to diagnose on site,
What causes rust? (doh!) cherchez la water.
There is a humidifier, there is an AC coil. There are condensate drains for each. Condensate is techy talk for water, makes us sound smarter.
There is also rust on the vent connector elbow joints, an indication that the chimney may be too big or not venting properly, causing condensation of the water vapors of combustion, as this condensed water get mixed with Carbon Dioxide, a fairly corrosive acid forms that rusts metal quickly and destructively.
Something is badly effed, refer to a technician.