Water Heaters - Pilot light not stay lit when burner is on.

The pilot light on my water heater goes out while the main burner is lit and heating water. I replaced the thermocouple with no success. I lit the pilot light on the heater and turn the thermostat down so that the main burner would not light and the pilot light did not go out. I then turn the thermostat up and the main burner lit and after a couple minutes the pilot light went out. I was doing some research and found some information on something call the spill switch. Could this be the cause of the problem or is the problem somewhere else?

Sounds like the problem is lack of combustion air, causing burner and pilot to "float " out. Is this a newer style heater? The FVIR style? This would be the type you can't light the pilot with a match, rather you must use the igniter.
If yes, try cleaning the arrestor plate beneath the burner. Hopefully it is the model you can use a brush to clean.

The heater is eight years old and I am able to light the pilot with a match. I am considering replacing the pilot with a new pilot assembly. If this does not solve my problem could there be a problem with the heater control?

I too am having this problem and have talked to people and had plumbers out to look at it and tried out everything that they have told me to do. One thing that did work for awhile is to turn down the temp. on the water. This seemed to work for awhile but now it is turned so low the water is barely warm enough for a shower. I wrote the company that made my hot water tank because the last plumber wanted to replace and it is only eight years old. They said to replace the thermostat so I think I will try this before I replace the whole tank. In the mean time if you find something that works please post it.

If you give me the make and model, I will get more info so I can advise properly.
If your water heater has a spill switch, it could be possible. But some spill switches must be manually reset.

More info and pictures may help

My water heater is located in a crawl space and some dirt had compiled underneath the water heater. I believe when the burner ignited it depleated the oxygen causing the sufficating the piliot light. After I cleaned out the dirt underneath the water heater the problem went away.