Proper Name of Thingy

[Mark P]

What is the name of this thingy. I believe it is a flame sensor. Condensate was dripping directly on top of it and wanted to use its proper name.

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[mgbinspect]

Isn't that an igniter? It's looks like possibly the two electrodes that a spark jumps between to ignite the pilot.

[Marc]

Looks like a flame prover to me. When the rod becomes hot enough, it emits electrons like the cathode on those old television vacuum tubes. The other electrode (the cool one) collects them. A circuit then detects that a current is flowing and allows the main gas valve to either open or to remain open when the bypass switch is released.

I guess the mention of cathodes on vacuum tubes didn't ring a bell with too many of you, but that's the truth. If you heat up a wire hot enough, it will emit electrons for a suitably charged conductor nearby to collect.

Marc

[Richard Saunders]

It's called a thermocouple.

[Erby]

The ignitor doesn't usually extend so far into the flame chamber with two rods. Most of the igniters I see are more of a glow plug type. They heat up like an oven element, gas flows over them and ignites. The only sparkers I usually see are on gas log sets with the little pushbutton (piezo-electric ignitor)

I'd also go with thermocouple of some type (like Marc says - flame prover). But most of the thermocouples I see are usually immersed in the pilot light flame to keep the valve open as long as the thermocouple is hot. Pilot light goes out, thermocouple cools off, valve closes to keep raw gas from leaking out.

??????

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[Bain]

It's a flame prover, as said before. It's sometimes also referred to as a flame sensor.

[Greg Booth]

It's both. I know it as a single-sense flame prover AND spark igniter.

[caryseidner]

It's a desert topping & a floor wax.

[Hearthman]

Direct Spark Ignition or DSI. The flame rod proves existence of a flame by rectification.

Electronic ignition systems are generally either DSI, Hot Surface Igniter or HSI, or Intermittent Pilot Ignition or IPI. The HSI is also called a 'glow coil' while the IPI is sometimes referred to as a 'spark to pilot'. All three use flame rectification meaning the flame conducts an electrical signal and rectifies it into a DC signal that the module is 'trained' to see.

HTH,