On 12/31/2014 7:52 PM, trader_4 wrote:
....

IDK what flame sensor you have there, but from the dimensions it looks
like it's a foot or more long, 1/2" in diameter and certainly not for a typical
home furnace. The one Danny has pics of does look like a small rod,
mounted on an insulator, connected to a wire. The descriptions I've
read about rod to flame conductivity also don't say anything special
about the reqts for the rod. They just say that a metal rod inserted
into a flame will conduct a current when voltage is applied. That would
seem to coincide with what he has, ie a metal rod on an insulator mount.

Those are commercial for larger boilers, etc., but the physics is the
same. There must be an isolated section for the current flow; otherwise
it would also be grounded. The _precise_ configuration is immaterial...

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