Quote Originally Posted by beenthere View Post
I've been basing the FR on metal pipe. If he has flex its even higher yet.
No flex, all metal! Pretty straightforward, one long main trunk with the furnace in the center, 4 runs on one side, 5 on the other, all running off the trunk sides straight out and up to the floor vents.

Quote Originally Posted by beenthere View Post
175 CFM in 6" metal, would be .22" FR. way too high, and too loud for resi.
What is FR? (Just curious.) As for how loud it is, well, there are two vents that are almost immediately above the furnace -- < 10 feet. They do make some noise. The remainder of them are basically silent -- so I naturally assumed the two loud ones are just a result of being so close to the furnace.

As far as good air mix. They didn't mislead you, its probably blowing out fast at most if not all registers. Which does give a good air mix.
Just it can be loud, and use more electric then need be.
Well, sort of. The 6" runs lead to floor vents that are very large -- smaller ones are 8x10, larger are 12x14. Immediately after the install, I had terrible stratification, somewhere around 5 - 8 degree difference between floor level and the 6 foot mark. (All ceilings are 9 feet.) Feet were freezing, head was warm lol. This is a 100 year old house, and the floor vents are basically built in and "framed" by the hardwood floor, so reducing the size is not an option. We blocked off roughly half the surface area of them from the underside, and it was a huge improvement, there is now about a 2 degree difference. (Is that reasonable?) They are the decorative type old Victorian grilles, so they really do nothing for the throw either. Oh -- and all returns are also at floor level, in the baseboards.

If they were to increase the size of some of the 6" runs, thereby reducing velocity, would I likely be getting back into stratification problems? Or should they be able to overcome that? I can live with the sound, if I'm going to be more comfortable. It's still WAY quieter than my old unit!!

Thanks again for all the help!!!