Originally Posted by
Corncob
Alright. Found enough info on the web to conclude a radius on the outside of a turn alone won't cut it. The inside radius is critical so I removed the tee and added a 2.25" radius turn on both sides. Reduced tee source leg area at same time (Spacepak ap engr didn't like the opening volumn behind the ACM). Turning vanes would also work but I don't have the metal.
Reinstalled the tee and (properly) aligned the ACM on the blower exit (pre-drilled holes). Set the restrictor plate to straight vertical (no restriction) and leveled the Spacepak back up. Added last 8 ports the other day so have 30 total now.
Was out of time but ran the blower long enough to read 4 ports that I had previous numbers for (when there were 22 ports and the ACM was misaligned). It was pretty obvious as I moved the anemometer over the ports - it was spinning up like a turbo. I was over 35 on all 4 ports, 43 on 1. I'm up 2 or 3 cfm compared to the first test on these 4 ports - this with 8 new ports added.
I'll still have the issue with the restrictor plate increasing cfm on whichever leg of the tee its pointing at but I decided to make lemonade and add a second thermostat - one for the east side of the house and one for the west. Share control of the ACM with the Spacepak. Keep the blower motor original.
I reset max travel position of the restrictor plate to about 20 degrees ccw of vertical. Full cw rotation stops at about 15 degrees short of horizontal. Tomorrow I'll run cfm on all 30 ports at full ccw, vertical, 20 degrees cw past vertical, and full cw.
The ports are super quiet even with this velocity. You can hear the blower down in the crawlspace but I have no floor coverings, sheetrock etc.. My ducts are 100% sch40 pvc with long turn 90s where needed and pvc mufflers at port exits.
DIY. I read what you said in your first post. What your doing, is DIY.
"Better tell the sandman to stay away, because we're gonna be workin on this one all night."
"Dude, you need more than 2 wires to a condenser to run a 2 stage heatpump."
"Just get it done son."
Dad adjusted