Water Heaters - gas hot water heater that pilot light keeps going out (4 times in one week)

I replaced the thermocouple, cleaned out the flue pipe but it keeps cutting out./ Any suggestions?

proctor1970, Welcome to the DIY Forums.
You may have a draft that blows the pilot out. Make sure the cover on the side of the heater is secure and check for places that a draft could enter. It could be coming down through the flue pipe also. One other thing is to make sure the burner is clean and adjusted for a proper flame (no yellow flame). I have heard of burners that blow out the pilot when the main burner goes off due to bad adjustment. Good luck.

Thanks for your comments. I went over today and made sure the side access covers are securely in place. I also took apart the pilot and cleaned it. There was soot at the pilot end of the pipe. The pilot flame is blue at the bottom and yellow at the top. When I put the side access covers in place it seemed like the burner flame turned from blue to yellow/orange. The flue pipe connects to a flue header that services a total of 3 gas hot water heaters and 3 small gas boilers in a room that is about 12 feet by 12 feet.

Sounds like the pilots are starving for air. See if the pilots flames are adjustable. Good luck.