BTW - Pleease define "statification" in the HVAC world?. I looked it up on dictionary.com, but the definition was vauge.
"use velocity to reduce statification"
I believe he meant to say "stratification", which is a term to indicate stagnant air. When I was a kid my dad would smoke in the house, and whenever the central heat or a/c wasn't running, the smoke from his ciggies would just hang in a horizontal layer about 7 or 8 feet off the floor. The air at that level was stratified...it wasn't moving. When the heat or a/c kicked on, the horizontal layer of smoke would break up, as the air coming out of the registers would mix with the air in the room.
In your case, I would recommend a heat rise check be done on the furnace at its present blower setting and at the reduced blower setting and that be compared to what the OEM specs for that furnace.
Did you have a problem with heat reaching the lower levels of the room with the old system?
I brought this up to the installed and he showed me where I can ajust the speed of the air handler via jumpers on the circuit board.
The installer should be the one making these changes, if necessary, when he does a start-up. "Start-up?" says the installer. "What's that?" <scratches head>
Psychrometrics: the very foundation of HVAC. A comfort troubleshooter's best friend.