Zone dampers not working Carrier Board and Tstat, Water Furnace Unit

Hi All,

First time caller.

I have listed specs below. Long story short is I have replaced both zone dampers in the last 6 months (one confirmed bad motor with alternate 24v power source, one broken shaft) and one of them only closes a few degrees when I change zones and the other doesn't move at all. I have, for the time being, left both partially opened so I don't get too much static pressure. I have also listed my troubleshooting attempts. I am on my 3rd HVAC contractor. Original installer is out for sure (was WF dealer, now carrier), new WF dealer left me hanging for 6 months, third guy (who I really like) is a WF dealer but doesn't want to fool with the carrier board. I am to the point of replacing board with Honeywell Truezone, but afraid I may be missing a simple fix.

Specs:
20 year old Waterfurnace Geo-thermal unit (Premier II I believe)
Carrier Comfort Zone II board and tstat
2 zones controlled from 1 tstat. Upstairs has sensor
New dampers are power open / power close

Troubleshooting:
Replaced both dampers (contractor #2 did one, I did the other)
Have tested bother dampers off of system
checked damper fuse in board - OK

Example:
When I run zone 2 up 10 degrees above current temp and run zone 1 down, zone 2 damper only closes about 15% (zone 1 opened manually)
When I run zone 2 down and zone 1 up - zone 2 opens back up and zone 1 stays closed

So, zone 1 damper won't actuate at all on system
Zone 2 doesn't full function

Following LEDS are lit when system is idle:
D16, D18, D20 - cannot find reference to these anywhere.


Thanks in advance!