Furnace Circulation (Internal)

I have called this out for evaluation by a qualified HVAC tech, but I wanted your opinion on what I think.

There was corrosion from a previous leak inside of the furnace. It had corroded a small hole in the plate under the induction fan. My thoughts are that with the hole the circulation fan in the base of the unit can now pull air (incl gases)from the combustion area of the furnace and circulate it around the home.

The hole is not in the combustion area.

I would say you are correct, the hole is under the induction fan, the pic is was taken underneath in fan compartment right? IMO that furnace should be replaced unless it is possible to remove the rusted metal and replace it, probably not worth the trouble, but let the HVAC tech make the call as you did.

You are correct. But your only job is to observe and report what you see.

The rest is up to someone else. Fix/Replace, who gives a crap?

#1 It is broken, and a life threatening hazard.
#2 I would red tag the thing and notify Agent/Home Owner - Tenant immediately.

What to do “NOW” is more important than what to do “Next”.

The return plenum has a much higher negative pressure than the flue. It’s not “if” , it’s about “how much” combustion gas is discharged into the house. When the induced draft fan shuts off, the blower keeps running and pulls everything backwards.

I could see it being a problem if it was a mid efficiency furnace but its not.
Would you have a pic from further away?

what difference what difference would that make?

HE gas furnace have a sealed combustion/heat exchanger and that corrosion/hole shown in the picture is not in the combustion/heat exchanger. The mid efficiency doesn’t have a sealed combustion/heat exchanger and any CO leakage could get recirculated by the furnace circulation fan into the home.

At the bottom right corner, you’ll see a door switch.
If the burners were not open to the blower, there would not be a door switch.

In the top left (next to the white wire) I see the face place of the burner compartment.
This is where the fire goes.

I see a hole in the plate between there and the blower.

Why are we discussing something that does not exist? The endshot burners are open to the blower compartment. Period.

The blower runs a purge delay when the burners and induced draft fan shut off. We call that a back draft from the flue…

Can’t get much clearer than that, Thanks David!

Thanks for the info David!
In my initial response, I was thinking of a sealed combustion unit and not a unit where the endshot burners are open to the blower compartment (see attached) which is why I ask for a pic from further away.