I have a state select gas water heater.
Model# gs640ybvit
Seriel # c07a022941 there are two lites on the control. The first and the last one (c) its locked out. Any ideas. Thanks

Go here for the manual: www.americanwaterheater.com/support/manuals/energysmart.pdf . When you power up the heater it will give a number of flashes which will tell you what the problem is. Apparently something is shorted out for it to lock out like that, probably an element. If it is under 6 years old it is under warranty. Be sure to check the anode rod if you want to protect the heater from corroding. You can turn off the power and check the elements with an ohm meter and see if there is continuity and whether there is a reading from the power terminal(s) to ground. If there is any reading to ground or if there is a high resistance you need a new element. Use this calculator: http://www.the12volt.com/ohm/ohmslawcalculators.asp to determine if the resistance is too high, but if the element is rated at 11 amps the resistance will be about 20 ohms. Divide ohms into voltage (220-240) on nameplate to get amperage. As long as it is close it is okay. If you have a reading of 1000 ohms you know the element is bad. Check your t-stats which should read zero ohms, or close to zero if water is cold, and if wires are disconnected there should be no reading to ground. I hope this helps. If you don't have a meter you can find a good digital meter for $10 or so at many stores. DrTom4444

If it is the first lite and the last lite it means it detected harmful vapors I am having the same problem it happened to me before and I had to reset it I can't remember how to do it but I need to do it again I got flooded and it didn't get wet but it detected vapor I can't remember who I called to get the code to reset and my book got wet and ruined
Ugh