On 1/11/2016 3:26 AM, Don Y wrote:

All I know is that it's a Lennox and it's giving that error code.

While I'm sure the furnace repair guy will get there before I even get
a reply on here, I thought I'd post this to see if any of you know
anything about it... I always like to learn new home repair stuff.

What's the purpose of these switches and what could be wrong?

The switches verify the presence of flame where it SHOULD be and the
absence of flame where it SHOULDN'T be!

You (he) could have a blocked heat exchanger which is preventing
the flames from flowing up through it and, instead, backing up
into the blower compartment (*outside* the heat exchanger).
Likewise, a blocked flue or something blocking the combustion
relief (not enough air to support combustion).


The switches can usually be reset, manually. But, this is A Bad Idea
and really should only be done by a qualified technician - just to
run the furnace long enough to understand why it/they are tripping.
They function similar to a fuse: they should NEVER trip -- doing so
means something is likely very wrong.

You (he) may be able to get the furnace to run by reseting them,
but run the risk of CO poisoning, fire, etc. as the reason for
their initial trip probably hasn;t been fixed!



Sometimes it's wind across or down the chimney that
causes the problem. There is a good chance it's a
rare thing, and the furnace is okay, now. In western
NYS, it was very extremely windy last night.

--
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Christopher A. Young
learn more about Jesus
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