Within 24 hours, the furnace acted up again. Picked up a control board on Monday from local dealer, last one they had, which was priced at $225. They said board prices had gone up, and the future replacements would be higher.

Took me an hour to replace the board which included time reading and rereading the installation instructions, although technicians such as Bubba should be able to do it in 15 minutes. I took it slow and triple checked all wires according to Ignition Control Replacement Kit Instructions and Figure 4. Be sure to write wire colors on the diagram, such as ACB COOL blue, ACB LOW yellow, and ACB HEAT red, and do not forget the six wires which connect to the five screw posts. When mounted with P20 Plug at bottom left, five screw post wires from top to bottom: white; yellow and red; white; blue; red.

Before heading into the attic, I sat on the couch and read the installation instructions. Box included replacement wires and plugs, so I connected plug J20, black wires from plug P166, ignitor, black wire between transformer and 120VAC TX, yellow wire between transformer and 24VAC RTN, and green/yellow wire to ground. This made installation rather simple.

Removed board is marked: Heatcraft EGC-1 REV C1, which had two distance posts between it and bracket.

Replacement board: Noval Systems EGC REV D, which had six distance posts between it and bracket.

Last point for newbies such as I: Board came with new mounting bracket which is quarter of an inch wider and required two mounting screws to be coverd on panel and two new ones to be drilled.