testing thermocouple

[dolluper]

On a test of a termocouple for a gas furnace what is the range between good and bad would 10 millavolts be on the good side or closer to bad ,does anybody know the ranges Thanks a bunch

 

[sangerwaker]

Re: testing thermocouple

For the three bucks they cost, I just replace them if they are even in question. I never knew you could test 'em.

 

[dolluper]

Re: testing thermocouple

It's not the cost as I always have a spare on hand but knowing if is faulity sure helps in figureing out what makes the pilot to drop and go out

 

[Pascal]

Re: testing thermocouple

What is the voltage on the new one??? <br /><br />That would be good reference for the rest of us too.<br /><br />JD

 

[dolluper]

Re: testing thermocouple

I guess L had brain fade ,found out if it's good it will read 30 millavolts buddy contractor inlighten me 10 millavolts would be bad

 

[ob]

Re: testing thermocouple

They make a thermo-couple checker.I've got one left over from my A/C service days.The fitting that screws into the gas/safety valve attaches to the checker and you depress the spring loaded button on it for a ten count.If it stays depressed the thermo-couple is good.Most failures are a result of a heat cracked/stressed thermo bulb that hangs in the flame.<br /><br />Tip.. If you have an adjustable heat anticipator on you T/stat ,set it according to the amp rating of your pilot/safety valve.This will give your system the proper heat lag range.

 

[dolluper]

Re: testing thermocouple

I don't think I can adjust the stat it is a digital programable one but I still have the old mercury one that is adjustable ,if the digital one can be set how do you do it any suggestions OB

 

[Hoserpoppasmurf]

Re: testing thermocouple

To dolluper, the digital thermostats don't need the heat anticipator adjusted. They do it all "digitally".

 

[dolluper]

Re: testing thermocouple

Thanks there pop's that what I taught