My friend at his gear shop almost trashed a bunch of old HVAC panels... got curious and yanked the potentiometers and connectors. Had a unit come in with the exact same failed part two days later. Saved himself ordering a new board and a full day of downtime... now he always checks the "junk" pile first.
Disagree, sometimes tossing them is the only real option. Not every shop has the time or space to store and strip old units. The labor to pull those parts can cost more than just buying a new board. You found a system that works for you, but that's not the reality for a lot of smaller operations.