On several previous treads, people have stated a 12 inch straight length of flue pipe is needed on top of the draft hood. I have asked on two different threads for someone to point out the code requirement or manufactures requirements. Both times, there were no answers.
Last night I sent an e-mail to A.O Smith asking that question, the following is their reply:
DISCUSSION THREAD
Response (Brandon Freeman) 05/23/2007 08:59 AM
Darren,
Thank you for contacting us. If you are referring to standard atmospheric venting water heaters, then a straight vent run is not a requirement before a bend, although we do recommend it as it allows for better venting. The main thing to insure is that any horizontal run is on an appropriate rise and that the total horizontal is less than 75% of the vertical. Please let us know if we can assist you further.
Sincerely,
Brandon
So, unless someone can show some code requirement, let's put this HI folk-lore to bed right now!
Darren
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