thermo, coupler

[waterwelldude]

Is there any reason that a thermo coupler wouldn't last very long?
The one at my Fathers house has gone out, or quit working four time in the past year. The water heater is just over two years old.
What causes one to go bad in the first place?

 

[havasu]

Many times they get out of adjustment and also, depending on the gas, you can develop soot on them, causing them to quit working properly.

 

[waterwelldude]

Out of adjustment?
Do you mean how close or far from the flame?
They are not there long enough to develop soot.

 

[havasu]

If this is natural gas, often the air mixture is incorrect causing a yellowish flame. if this is the case, the local gas company will usually adjust this free of charge. Below was copied to save me some time:

If the pilot lights but the flame is a weak yellow flame, it will not get hot enough to heat the thermocouple to its set point allowing the gas valve to open.

A natural gas flame should be a bright blue with the tip of the flame having just a tinge of yellow. A propane flame should have a bluish green flame with a tinge of yellow at the tip. The flame should be strong enough to hit the thermocouple tip about 1/2 inch from the tip end. If the flame is weak or shaky looking, check to see that a breeze or draft is not blowing on it.

Adjusting the Flame:
There is usually a small screw on the pilot valve body that will adjust the flame. You may have to refer to the manufacturer's instructions to find the screw. Turn the screw as needed to adjust the flame throw.

Yellow Flame
A yellow flame is caused by lack of air and incomplete combustion. It can be caused by a dirty pilot tube tip.

Split Flame
This is caused by dirt in the pilot tube. Take a needle or small nail and gently clean the tube.

Flickering or Wavering Flame
A flame that flickers is usually caused by a draft.

 

[waterwelldude]

It is gas, not propane.
I will check on the flame placement and color.
There has to be something that is not quite right for them to stop working in just a short time.

Thanks for your help.
I will let ya know what I find out.

 

[Another-Plumber]

weak thermocoupling? or maybe the filter hasnt been cleaned..

 

[waterwelldude]

What filter?

So far its been ok, but then its only a few months old.