You may have a short or cold solder joint somewhere. I would reflow all solder pads and see what happens, you may have flexed the board when you removed it causing a cold or broken solder joint.
connect heatmeter to your PC with a Ethernet cable, and follow the steps here https://github.com/CapnBry/HeaterMeter/wiki/HeaterMeter-4.x-Software#wireless-client-setup-via-config-file-step-by-step-easiest-method
I looked at the pic of the board upclose and can see a few pins that don't have any/enough solder, and some that look like cold solder joints. If I where you, go over the whole board again with your soldering iron and reflow every pin just to be sure.
I thought the board had dampers that worked...........and yes I know I can stay with what works for me. Some of the stuff being posted as updates or latest software is way over MY head as I am not as EDUCATED as some others. It just seems to me at least that there is still tension here about...
Well, for me running just damper is no good with my burner setup, so I'll stick with the sync with fan. If I want to run just a damper, I would just open the vents. If it works, why try and fix it, this is smoking, not brain surgery.