Water heater thermocouple

[lalojamesliz]

hey guys, my mother in laws water heater crapped out, well the pilot won't stay lit. She lives in a nice mobile home and i saw how pricey those heater are
Well to replace a thermocouple does it have to be a specific one per each water heater or are they universal? I'd hate to blow that place up
Thanks in advance guys

 

[dogdog]

It's pretty much universal... if you are talking about the one that hold the pilot lit up. in a gas boiler/water heater.

One thing I have notice on my Boiler and water heater is that, some times the "universal" accessories/mounts that comes with certain packages doesn't fit. but other wise it will work if you are able to mount it , like reusing the old. Just make sure you thread the leads into the gas control by hand first and tighten the final step with a wrench, it gets cross thread very easily. by that time the control unit will cost you more.

There are different length of the leads also. they don't matter at least not the ones I encounter... just try to get one that is close to the length so you can tug it back nicely.. I think standard size is 24" and 36" (maybe, don't remember 100%)

 

[lalojamesliz]

Well this is a natural gas 30gal water heater. The pilot just won't stay on. I'm almost positive that its the thermocouple
I'll just have to go to a few places to see if I can find a match.....

 

[LS6 Tommy]

A water heater with no electrical components will have a thermopile. They're not interchangeable with thermocouples.

Tommy

 

[wayne55]

Have you tried really cleaning any lint or dust from the area. Some will have a screen that has to be kept clean for the pilot to stay lit.

 

[samss]

post the brand and model number. maybe someone can find a parts diagram.
sometimes the pilot burner, thermopile assembly has to be replaced.

 

[lalojamesliz]

I sent my son to remove the burner assembly but he wasn't able to. I'll get it in the morning and try clearing it.
I called the manufacturer and they just told me go to Lowe's and they can help me. Waste of time. The only useful information they gave me was that I need a 24" lead.

 

[lalojamesliz]

A water heater with no electrical components will have a thermopile. They're not interchangeable with thermocouples.

Tommy

The manual i found says it does..... wierd

 

[The Cobbler]

Thermocouples are normally universal.they come in various lengths . a longer one can be used by gently coiling the excess if you can't find the proper lenght

 

[The Cobbler]

A water heater with no electrical components will have a thermopile. They're not interchangeable with thermocouples.

Tommy

Doesn't a thermopile produce millivolts to run the remote stat?
a water heater has a mechanical stat

 

[samss]

A pdf of the owners manual is available. Google the model number mfg1f3030t3nov
Page 22 shows the procedure to replace the thermocouple.
www.uscraftmaster.com › pdf › manuals › BFGmanual

 

[LS6 Tommy]

Doesn't a thermopile produce millivolts to run the remote stat?
a water heater has a mechanical stat

Thermopiles do create a millivolt signal, more than a thermocouple. The MGV is in series with it and the mechanical stat. They can be used with remote stats, too, but the stat has to be a millivolt stat, you can't use just any mechanical stat.

Tommy

 

[LS6 Tommy]

The manual i found says it does..... wierd

It's probably because the two terms are often used interchangeably. From a purely technical standpoint, I can't see how it could. I could also be very wrong. All a thermocouple does is make enough millivolts to allow a powered gas valve to open if the pilot is lit. A thermopile is multiple thermocouples that create enough millivolt power to operate the gas valve by itself.



Tommy

 

[engineer2]

All a thermocouple does is make enough millivolts to allow a powered gas valve to open if the pilot is lit. A thermopile is multiple thermocouples that create enough millivolt power to operate the gas valve by itself.

As an experienced fireplace fighter, you are correct. These are often called "standing pilot millivolt systems."

The thermocouple detects if the pilot is lit. If no pilot light is detected, then the gas valve won't open. Used in powered and unpowered systems.

A thermopile uses the heat from the pilot light to generate enough electricity to operate the solenoid inside the gas valve. Some gas valves combine the functions of the thermocouple and the thermopile since the thermopile 'proves' the pilot light is lit.

 

[dogdog]

I sent my son to remove the burner assembly but he wasn't able to. I'll get it in the morning and try clearing it.
I called the manufacturer and they just told me go to Lowe's and they can help me. Waste of time. The only useful information they gave me was that I need a 24" lead.

Then go to HomeDepot... or order from Amazon or any plumbing / fireplace stores. they will have these. 24" or 36" which ever one you get your hands on.
I don't remember what brand the Lowes carries, HD is Everlast and if you are ordering from Amazon, the Honeywell brand is pretty good.


I always kept one for used with both my AO smith gas water or the Boiler.. and for some reason my boiler always kept killing the thermocouple more often than then water heater. Doesn't matter.

 

[dogdog]

Have you tried really cleaning any lint or dust from the area. Some will have a screen that has to be kept clean for the pilot to stay lit.

I think he have to set that knob to Pilot, press down, then reach in and lit it with a long lighter or if that unit have a pizo electric button, he'll have to press it till it is lit...

Once the pilot is lit, Keep pressing down on that pilot button to keep the gas flowing for a while like a minute or two maybe more... till it can self sustain. If you released the pilot button and the pilot flame does not self sustain then something is wrong like defective thermocouple, or if new thermocouple installed incorrectly, flame not heating the thermocouple. etc.

Then move the knob to ON.

There are only three positions. Off, Pilot or On. and only on the Pilot Position you can depress the knob down to open the valve manually to lit the pilot. This is pretty much universal as well.