Water Heater Valve

[tonyn1]

I have an Envirotemp model G1H4040T3NV water heater that has a problem of the pilot light not staying lit. I previously replaced the thermocouple and that fixed the problem for a few months, but then it started not working again. I tried another thermocouple, but it did not do it this time. I found a control gas valve that looks exactly like the one I have on there, but the part numbers are different. They are both Robert Shaw valves, and the original is a part number 66-178-335, while the new one is a 64-LF-376. What is the difference, if any?

 

[Smooky]

Here is some replacement info:
http://www.uni-line.com/modules/catalog/Product.aspx?singlePart=false&prodID=367984

 

[Sponsor]

 

[Dj2]

Check the pilot gas supply in two locations: at the pilot outlet and at the gas valve, verify that gas is reaching the pilot.
No gas at the pilot and yes gas at the valve? your problem is the tube.
No gas at the valve? your problem is the gas valve. Either model will work.

Never light a match to verify gas.

 

[tonyn1]

Smooky, I can't find any info on my valves on the Robert Shaw site at all. dJ2, I've already checked the tube and blown it out. I don't think the valve is putting out enough gas to keep the pilot lit, or something like that. I've already tried replacing the thermocouple for a second time. The pilot will stay lit for a little bit, enough to get the burner going to heat my water, but then goes out, as it doesn't heat again until I relight the pilot.