General question about thermocouples

[BigJohnfromCT]

From Wikipedia

"A thermocouple is an electrical device consisting of two dissimilar electrical conductors forming electrical junctions at differing temperatures. A thermocouple produces a temperature-dependent voltage as a result of the thermoelectric effect, and this voltage can be interpreted to measure temperature."

My question is: "When a t/c fails, does it just quit or will it produce less voltage over time at a given temperature?"

Occasionally, my Quad MVAE fails to continue firing. That is, the igniter heats up, the pellets begin to drop, they ignite but then the stove shuts down displaying the error code, "Min Firepot Temp". This message is displayed when the t/c does not detect the flame in a given amount of time. It does not happen every time. Any thoughts? Thanks for reading.

 

[Mt Bob]

Possibly and possibly.Thermocouples generally go "out of range".If was open,that would be a hard failure,you would know it.They can do pretty strange things.

 

[Ssyko]

Yes as the 2 metals degrade by oxidation, over heating and many other ways. As thermocouples become thinner, they tend to produce inaccurate temperature readings, usually readings that are lower than what the temperature really is. But most stoves that use TC’s have porcelain covers to protect the business end but they can over time slowly die. I have had my quad 19 yrs and had to change mine for the first time this year/ heat season

 

[BigJohnfromCT]

From Wikipedia

"A thermocouple is an electrical device consisting of two dissimilar electrical conductors forming electrical junctions at differing temperatures. A thermocouple produces a temperature-dependent voltage as a result of the thermoelectric effect, and this voltage can be interpreted to measure temperature."

My question is: "When a t/c fails, does it just quit or will it produce less voltage over time at a given temperature?"

Occasionally, my Quad MVAE fails to continue firing. That is, the igniter heats up, the pellets begin to drop, they ignite but then the stove shuts down displaying the error code, "Min Firepot Temp". This message is displayed when the t/c does not detect the flame in a given amount of time. It does not happen every time. Any thoughts? Thanks for reading.

Thank you to Bob and Ssyko for your input. I think I'll order a new one just to have on hand.