On Tue, 20 Dec 2011 17:34:30 -0500, " Tuuk" wrote:

Ok,

I changed the main fan board, and still the exact same condition happens.

Even though the thermost is off, even disconnected, as soon as I turn the
main toggle switch for my furnace, both main blower fan and exhaust fans
immediately begin and nothing else happens.

I just unplugged on leg from the high limit switch, then one leg from the
low limit switch then both together

Same, nothing.
Any suggestions?

Thanks

Sorry about the previous duplicate posts, the first one came back as unavailable
when I tried to download it myself. That normally only happens when a post
expires, but I digress.

Anyway, short the 2 terminals on each limit switch - one switch at a time with
the other(s) connected normally. I would start with the blower limit switch.
That would be my best guess.

I believe this furnace was made by Heil. I'm out of it now, but I've installed,
(and repaired) more of their furnaces and air conditioners over the years than I
could count. They are my favorite make. They are the same furnaces that Sears
sells, and they also used to be sold under the "Tempstar" brand. That is if they
are, as I believe, made by Heil.

Best of luck,
Bob KB2ZGN


***********************
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