Igniter Dumb question of the week

[mralias]

I have to ask...Could someone explain to me just how does the igniter wear out and the same question for the thermocoupler. In looking at both they appear to be nothing more than a loop wire. Sorry, I lay awake at night thinking about stupid stuff like this.

 

[smalltown]

Not a metallurgist, but my guess on the igniter is that every time it heats up it expands a little then obviously when cooling down returns to its normal size. I imagine metal fatique takes its toll over time, and it develops places that are higher resistance. At some point these spots fail (go open) and the igniter fails.

 

[imacman]

Not a metallurgist, but my guess on the igniter is that every time it heats up it expands a little then obviously when cooling down returns to its normal size. I imagine metal fatique takes its toll over time, and it develops places that are higher resistance. At some point these spots fail (go open) and the igniter fails.

I agree....the same reason a incandescent light bulb burns out eventually.

 

[mark d fellows]

Not a metallurgist, but my guess on the igniter is that every time it heats up it expands a little then obviously when cooling down returns to its normal size. I imagine metal fatique takes its toll over time, and it develops places that are higher resistance. At some point these spots fail (go open) and the igniter fails.

Sounds like pretty sound reasoning.