Our furnace wouldn’t fire on cold days. The landlord hired these guys, and they were able to identify a pressure switch signal that wasn’t passing through the controller board. The board had no obvious damage, but with a cable bundle attached that had some heft to it–I think the vibration and shaking of the house from street construction AUG-SEP busted one of the traces inside the board.
They had it replaced and firing very quickly. The technician drove about a half-hour out to get the replacement part.
While I don’t know how they handled cost, the service was second to none. Watching the technician’s work, it was clear that he had the electromechanical underpinnings of many of these units committed to memory–knowing exactly where to test and which voltage or signal to look for.
While there wasn’t any obvious evidence other than more flex than a new board, the natural expansion and contraction of the board with an imperceptible crack in it–could explain why it wouldn’t operate on cold days, but would on warm ones.
I’m two days into this, and the problem has not returned.