Pilot Light goes out on heater

I have had success in the past with removing and cleaning the thermocouple head with a piece of Emory cloth. Reinstalled and worked fine. Over time carbon builds in it.
If that doesn't work, replace it as mentioned above.

Some Thermocouples connect to the Gas Valve with what looks like a tubing flare nut. It's an Electrical Contact, so do NOT crank it down like you might if it carried LP Gas. Just clean and snug about 1/4 turn once it touches. Too tight and it'll short out.

Yep......
Thermocouple is first thing to suspect.

Pilot flame not staying lit:
Thermocouple not hot enough....not holding knob on long enough
Thermocouple loose...tighten connection at gas control
Weak thermocouple...replace thermocouple
Weak gas control magnet...replace gas control
Defective ECO (hi temp t-stat---comes out back of gas control and goes into WH tank) in gas control....replace gas control

Try changing the thermocouple. You can buy them at a hardware store, and install it yourself. Should be less than $20 part. Take out the old one, and take it with you. You need to match up the threads, but the other end has some flexibility in shape, so it does not need to be exact, but close enough that it will fit in the old space.

Fred.

Are You talking about an older manual light model or a newer unit with DSL?

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