On 11 Jan 2004 14:18:08 -0800, the renowned jim rozen
wrote:

In article , Gunner says...

...the flame rod is a device that puts 100 or so volts on the flame
rod, which is exposed to the flame, and uses flame rectification to
convert this to dc and then to ground. It senses the ground path

Thanks, I've learned something today. I've never
seen those, all the flame decectors I've been aware
of are either thermocouples or CdS photocells.

Some of the big industrial ones use a special electronic gas tube that
is sensitive only to ultraviolet light. They are sunlight-blind even
without a filter but respond to the UV given off by a flame.

Also the SiC ignitor modules in our oven - which always
seem to burn out at the *worst* time!

Same thing with the hot-surface ignitor in our furnace. I should pick
up a spare.. thanks for reminding me.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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