Old Janitrol Furnace Exhaust

[chris vis]

Well, I guess this is one way to introduce myself to the forum. I wanted to share a photo from an inspection I just completed. The exhaust from the Janitrol furnace has a screen duct taped onto the bottom. I have never seen anything like it in my life. I know it cannot be correct, but based on the age of the furnace I cannot find anything to tell me what the correct part should look like, or why the homeowners would ever do something like this that could let flue gases into the home? Any ideas? This is one of the craziest things I have seen and I need to understand WHY?

[Raymond Wand]

Two wild guesses.
1. Stop inquisitive children
2. Prevention of insects

It should be a free open to dilute exhaust temps and to improve draw me thinks.

[Stephen G]

Looks like the slope is downhill, the 'duct tape has to go' and the screen may not last much longer...I havent seen metal screen in awhile :eek:

post edit.. it may not be a metal screen, whatever is behind its rusting and the bottom is full of whatever...

[Billy Stephens]

Looks like the slope is downhill, the 'duct tape has to go' and the screen may not last much longer...I havent seen metal screen in awhile :eek:

post edit.. it may not be a metal screen, whatever is behind its rusting and the bottom is full of whatever...
.
It looks like an old Dryer vent Box. ( Installer Went for the big hole All ready in the Wall.)
.

[Steven Saville]

Screen likely placed on draft diverter box to keep birds or possibly squirrels from entering home via chimney. Have on occasion seen this happen. Screen should be removed as mentioned so as not to hinder proper draft.

[Tom Rees]

Chris, Welcome. Just FYI this should be in the HVAC section, you will get more views and replies. Am I missing something, why is this even open on the bottom?

[Don Halligan]

Chris,
This is the diverter and should not be blocked in any fashion. This is designed to allow dilution air to enter into the vent. It looks like the screen is partially plugged as well - what this will do is cause a greater draft through the heat exchanger and draw more heat out of the furnace and considerably reduce the efficiency of the furnace.
It's a simple fix - remove the screen.
It they are having problems with birds, squirells. chipmonks, etc. they need to make sure an appropiate chimney cap is installed.
I would also state that this furnace is past its life expectancy and they should consider upgrading to a more energy efficient furnace.
Welcome aboard,
Don Halligan