My water heater is a copper lined all craft working well. There is a rectangular box that connects to the water heater and then the flue. It has three holes now (metal tape over holes).
I took the part off (pic attached) and plumbing supply places tell me to get one fabricated. One place called it a diffuser. All are confused by it and one said has not seen one for 15 years.
A fabrication place said it would cost 250.00 to get a new one made.

It is open at the bottom with 3 baffles inside. I am guessing that it is like a fireplace, it needs oxygen to send the fumes up the chimney?
Part of my problem with it is that I do not even know what to call it. Do you know? The internet cannot help me find it or info about it if I do not know what to call it.
Two pictures can be seen at this site at the bottom:
[www.flickr.com]

Thanks for any help.



Edited 1 times.

The pictures that you are referring to can't be viewed unless you are a member of the site you uploaded them to.

Thank you for letting me know. I have changed the url. This should work.

I'd find another sheet metal shop.

it is some kind of an inline draft hood ??? made for a situation when you don't have enough headroom for that mushroom shaped draft hood?

That must be it. Thank you.
This must be the original part of the 55 year old water heater.