anyone know how to tell if a water heater thermocouple is bad?

[isubeatle]

Last night i went to shower and the water was only kinda cold and wouldn't heat up. So i checked the water heater and the pilot light was out. I turned the knob off and waited a few mins and then turned it to pilot, pressed the button down and lit the pilot. It lit up and stayed lit when i had the button held down, which i did for a min or so to let it heat up. As soon as i let go of the button the flame goes out.


If i had to guess, i'd say the water heater is about 10 to maybe 15 years old and has always worked amazing. So from what i can tell from videos on the web it seems like the thermocouple has gone bad. It looks burned out and a kinda nasty and i tried my best to squeeze in there with some sand paper to get some crap off but it didn't seem to help much.

I'd rather buy a new one and get it over with then have to spend $40-50 to have someone come tell me it's not a simple fix and then buy a new one. But if it is just ther thermocouple, i know that's a really cheap part and i'm fine with paying for the labor to get it replaced.

thanks!

the attached image is almost exactly what it looks like

 

[ISUAgronomist]

Sounds like the correct symptoms for a thermocouple to me.

 

[CtownCyclone]

Matches the symptoms I had when my thermocouple checked out. Pick up a new one and swap it out.

 

[VTXCyRyD]

I'm going to agree with everyone else. Same symptoms I had when I replaced it.

 

[Sparkplug]

It's easy. I've done several. Learned how hanging around a plumbing shop

 

[ISU_phoria]

Definitely the thermal couple. These go out in Water Heaters all the time. You can probably google your brand/model and get a replacement online.

Big box/ hardware stores have generic options too, that fit most HW heaters, but there a some brands where you have to replace a larger pre-packaged unit that includes more than just the thermal couple.

Overall - it's a pretty common & easy fix.

 

[Acylum]

If it is 10 - 15 yrs old you might want to consider just replacing it anyway. Also, I had a similar problem once but the pilot would only go out at night. During the day it was fine. Nobody could figure out what was happening. Finally somebody determined it was the actual gas meter outside that was causing the problem. It was winter and the colder temps at night were causing some kind of restriction so that the furnace would work fine but not enough gas would get to the water heater. Best part is the fix didn't cost me anything.

 

[TruClone]

Try cleaning it first. Use a dollar bill. I have done this and it works well. If this does not work then it really does need replacing.

 

[isubeatle]

well it was the thermocouple and it cost me $100 to fix. He told me it was more like 25 years old. :swoon:

however, everything else looks really good he said and if we've never had any problems with it then there's no reason to replace it. I would've replaced the thermocouple myself, but it was old enough that the burner setup was different then anything i could find instructions for. And when it comes to gas i'm never very comfortable and have no problem paying for a trained person to do it.