On Saturday, December 20, 2014 8:27:16 AM UTC-5, Danny D. wrote:
trader_4 wrote, on Sat, 20 Dec 2014 05:19:01 -0800:

The video wouldn't play in Internet Explorer, just sound. In Chrome
it played for me and clearly it shows 1 long flash, 5 short flashes,
followed by continuous flashes. The other video, with the door on,
just shows it flashing continously, no patterm.

Thanks for taking a look at it, because I saw exactly the same thing.

The video with the door on was taken after it was running for ten or
fifteen minutes, but with no heat, so I crawled into the crawlspace
where the heater was and taped the flashing.

There was nothing whatsoever done with the line voltage of this
furnace, at least not on purpose. No electricians came to the house.
And nothing was done on the furnace whatsoever.

So, for the line voltage to reverse, that would be odd.

Two problems. First the table says the codes are given by the number
of long flashes and short flashes, which would lead you to believe
the long flashes should come first, not the other way around.

I can't tell if the continuous flashes are long or short.

Second, no matter, there is no table entry for 1-5 or 5-1.

I did see, as you saw, that the first few seconds of flashes
were not the same as the rest of the flashes. I didn't know what
to make of it, but you discerned a 1-5, which makes your timing
better than mine.

Another possibility would be that the control board was replaced
previously with a different type that has different codes.

Ah. I understand what you're saying. If the control board doesn't
match the cover secret decoder ring, then that might explain a lot.

We don't know the sequence of what comes before those videos.

I'll snap a new "reboot" video today, with the power turned off to
the furnace, for a few hours, and then turned back on and started
right up so we get the "initial" sequence of flashes.

It doesn't have to be turned off for a few hours, just turned off and
back on. Record what it does when power comes back on without a call for
heat. If it shows normal, stays that way for a few mins, then turn
up the thermostat and see what happens.

Another thing, you're not operating the furnace normally. You have the
cover off, furnace powered up and you're depressing the door safety switch
to initite it. For all we know that 1 -5 sequence could mean "detected
door switch open". Power it up with the door switch closed, either with
the door on, tape over it, etc.